Search

P/TGMS (Photo/thermo-sensitive genic male sterile) lines are crucial resources for two-line hybrid rice breeding. Previous studies revealed that slow development is a general mechanism for sterility-fertility conversion of P/TGMS in Arabidopsis. However, the difference in P/TGMS genes between rice and Arabidopsis suggests the presence of a distinct P/TGMS mechanism in rice. In this study, we isolated a novel P/TGMS line, ostms19, which shows sterility under high-temperature conditions and fertility under low-temperature conditions. OsTMS19 encodes a novel pentatricopeptide repeat (PPR) protein essential for pollen formation, in which a point mutation GTA(Val) to GCA(Ala) leads to ostms19 P/TGMS phenotype. It is highly expressed in the tapetum and localized to mitochondria. Under high temperature or long-day photoperiod conditions, excessive ROS accumulation in ostms19 anthers during pollen mitosis disrupts gene expression and intine formation, causing male sterility. Conversely, under low temperature or short-day photoperiod conditions, ROS can be effectively scavenged in anthers, resulting in fertility restoration. This indicates that ROS homeostasis is critical for fertility conversion. This relationship between ROS homeostasis and fertility conversion has also been observed in other tested rice P/TGMS lines. Therefore, we propose that ROS homeostasis is a general mechanism for the sterility-fertility conversion of rice P/TGMS lines.

PURPOSE: This study characterizes attitudes and decision-making around the desire for future children in young women newly diagnosed with early-stage breast cancer and assesses how clinical factors and perceived risk may impact these attitudes. METHODS: This is a prospective study in women

The ex situ population of the endangered black-footed ferret (Mustela nigripes) has been experiencing declines in reproductive success over the past 30 years of human-managed care. A potential cause may be environmental-dependent inbreeding depression with diet being one of the contributing factors since ferrets are not fed their natural diet of prairie dogs. Here, we generated and analyzed semen proteome and transcriptome data from both wild and ex situ ferrets maintained on various diets. We identified 1757 proteins across all samples, with 149 proteins unique to the semen of wild ferrets and forming a ribosomal predicted protein-protein interaction cluster. Wild ferrets also differed from ex situ ferrets in their transcriptomic profile, showing enrichment in ribosomal RNA processing and potassium ion transport. Successful fertility outcomes documented for ex situ ferrets showed the strongest association with the semen transcriptome, with enrichment in genes involved in translation initiation and focal adhesion. Fertility also synergized with the effect of diet on differentially expressed transcriptomes, mainly affecting genes enriched in mitochondrial function. Our data and functional networks are important for understanding the causes and mechanisms of declining fertility in the ex situ ferret population and can be used as a resource for future conservation efforts.

Purpose of reviewFertility concerns are common among young women diagnosed with breast cancer, as systemic therapy increases the risk of premature ovarian insufficiency and delays family planning. Here, we review the impact of systemic therapies, including chemotherapy, endocrine therapy, HER-2 directed therapy, PARP inhibitors, and immunotherapy, on ovarian reserve.Recent findingsWith an improved understanding of disease biology, fewer women are treated with gonadotoxic chemotherapy. There are limited data on the fertility impact of novel targeted treatments and immunotherapy, though preclinical and preliminary studies suggest an impact on fertility is possible. Notably, a recent study investigated the outcomes in women who interrupted adjuvant endocrine therapy to attempt pregnancy.SummaryFurther research is needed to characterize the fertility impact of novel therapies in breast cancer. Individualized fertility counseling should be offered to all women to discuss the possible impact of therapy on ovarian reserve and options for fertility preservation and timing of pregnancy.

OBJECTIVE: To determine the association between fertility treatment, socioeconomic status (SES), and neonatal and post-neonatal mortality. STUDY DESIGN: Retrospective cohort study of all births (19,350,344) and infant deaths from 2014-2018 in the United States. The exposure was mode of conception-spontaneous vs fertility treatment. The outcome was neonatal (

There has recently been an explosion of studies implicating the human microbiome in playing a critical role in many disease and wellness states. The etiology of abnormal semen analysis (SA) parameters is not identified in 30% of cases; investigations involving the semen microbiome may bridge this gap. Here, we explore the relationship between the semen microbiome and alterations of sperm parameters. We recruited men presenting for fertility evaluation or vasectomy consultation with proven biological paternity. SA and next generation sequencing was performed. Differential abundance testing using Analysis of composition of Microbiota with Bias Correction (ANCOM-BC) was performed along with canonical correlational analysis for microbial community profiling. Men with abnormal (N = 27) sperm motility showed a higher abundance of Lactobacillus iners compared to those with normal (N = 46) sperm motility (mean proportion 9.4% versus 2.6%, p = 0.046). This relationship persisted on canonical correlational analysis (r = 0.392, p = 0.011). Men with abnormal sperm concentration (N = 20) showed a higher abundance of Pseudomonas stutzeri (2.1% versus 1.0%, p = 0.024) and Pseudomonas fluorescens (0.9% versus 0.7%, p = 0.010), but a lower abundance of Pseudomonas putida (0.5% versus 0.8%, p = 0.020), compared to those with normal sperm concentration (N = 53). Major limitations are related to study design (cross-sectional, observational). Our results suggest that a small group of microorganisms may play a critical role in observed perturbations of SA parameters. Some of these microbes, most notably Lactobacillus iners, have been described extensively within other, fertility-related, contexts, whereas for others, this is the first report where they have potentially been implicated. Advances in our understanding of the semen microbiome may contribute to potentially new therapeutic avenues for correcting impairments in sperm parameters and improving male fertility.

Understanding the evolutionary mechanisms underlying the maintenance of individual differences in behavior and physiology is a fundamental goal in ecology and evolution. The pace-of-life syndrome hypothesis is often invoked to explain the maintenance of such within-population variation. This hypothesis predicts that behavioral traits are part of a suite of correlated traits that collectively determine an individual's propensity to prioritize reproduction or survival. A key assumption of this hypothesis is that these traits are underpinned by genetic trade-offs among life-history traits: genetic variants that increase fertility, reproduction and growth might also reduce lifespan. We performed a systematic literature review and meta-analysis to summarize the evidence for the existence of genetic trade-offs between five key life-history traits: survival, growth rate, body size, maturation rate, and fertility. Counter to our predictions, we found an overall positive genetic correlation between survival and other life-history traits and no evidence for any genetic correlations between the non-survival life-history traits. This finding was generally consistent across pairs of life-history traits, sexes, life stages, lab vs. field studies, and narrow- vs. broad-sense correlation estimates. Our study highlights that genetic trade-offs may not be as common, or at least not as easily quantifiable, in animals as often assumed.

Despite rapid evolution across eutherian mammals, the X-linked MIR-506 family miRNAs are located in a region flanked by two highly conserved protein-coding genes (SLITRK2 and FMR1) on the X chromosome. Intriguingly, these miRNAs are predominantly expressed in the testis, suggesting a potential role in spermatogenesis and male fertility. Here, we report that the X-linked MIR-506 family miRNAs were derived from the MER91C DNA transposons. Selective inactivation of individual miRNAs or clusters caused no discernible defects, but simultaneous ablation of five clusters containing 19 members of the MIR-506 family led to reduced male fertility in mice. Despite normal sperm counts, motility, and morphology, the KO sperm were less competitive than wild-type sperm when subjected to a polyandrous mating scheme. Transcriptomic and bioinformatic analyses revealed that these X-linked MIR-506 family miRNAs, in addition to targeting a set of conserved genes, have more targets that are critical for spermatogenesis and embryonic development during evolution. Our data suggest that the MIR-506 family miRNAs function to enhance sperm competitiveness and reproductive fitness of the male by finetuning gene expression during spermatogenesis.

Background: Before pregnancy is recognized, ovulation, fertilization, and implantation must all occur. Physical activity and sedentary behavior may impact pregnancy success by altering each or all of these processes. The aim of this review was to review the association between physical activity and sedentary behavior with spontaneous female and male fertility. Method: PubMed/MEDLINE, Web of Science, CINAHL, SPORTDiscus, and Embase were searched from inception to August 9, 2021. Eligible studies included randomized controlled trials or observational studies, published in English, describing an association between physical activity or sedentary behavior (exposures) and spontaneous fertility (outcome) among women or men. Results: Thirty-four studies from 31 unique populations were included in this review (12 cross-sectional studies, 10 cohort studies, 6 case–control studies, 5 randomized controlled trials, and one case–cohort study). Of the 25 studies among women, the majority identified mixed results (n = 11) or no association (n = 9) between physical activity and female fertility. Seven studies reported on female fertility and sedentary behavior, and 2 found sedentary behavior was associated with decreased female fertility. Of the 11 studies among men, most of the studies (n = 6) found that physical activity was associated with increased male fertility. Two of the studies reported on male fertility and sedentary behavior, and neither identified an association. Conclusions: The association between spontaneous fertility and physical activity in both men and women remains unclear, and the association with sedentary behavior remains largely unexplored. [ABSTRACT FROM AUTHOR]

Recent sluggish economic growth in developed countries has become a cause for concern regarding the long-term sustainability of the global economy. Continuous declines in the total fertility rate (TFR) constitute an essential factor in stagnant economic growth in developed countries. In this paper, we utilize fixed and random effect models to examine the relationships of TFR with putative TFR determinants in G7 countries from 1980 to 2020. Our findings support the societal response hypothesis wherein the relationship between TFR and female labour force participation rate (FLFPR) is posited to be stable and positive. Furthermore, the present study confirms a positive relationship of crude marriage rate (CMR) and market childcare availability (MktCC) with TFR. A negative relationship between the ageing population (AGE) and TFR was observed, consistent with broad concerns regarding the impending economic impacts of population ageing in developed countries. [ABSTRACT FROM AUTHOR]

Breeding soundness evaluation (BSE) is the best methodology to estimate the fertility potential of future bulls and performing indirect selection for their fertility. However, the outcome of the BSE is influenced by several factors, including genetics, environment, and BSE guidelines. Herein, in this retrospective study, our first aim was to characterize the reasons for failure in 46,566 BSE from 2-year-old beef Bos indicus bulls (Nellore) born from 1997 to 2018. Our second aim was to determine whether or not BSE was associated with reproductive potential improvement of the bulls over the years. Due to changes in the BSE criteria, we used the same dataset, but only bulls born from 2002 to 2018 were included resulting in 35,856 BSE. For the second aim, the effect of the year and farm were included in the model of the multivariate logistic regression. We also determined if the main reasons for BSE failure decreased over time. Bulls were classified as approved (satisfactory potential breeders and qualified for natural breeding service) and not approved (deferred and unsatisfactory potential breeders). The reasons for BSE failure in Nellore bulls were poor semen quality (53.1 %) and physical defects (46.9 %), with the main physical defect being testis abnormalities (19.7 %). The overall percentage of bulls approved each year was 87.1 %, with no improvement over the years of study. However, the percentage of approved bulls at the first BSE increased over the years (P < 0.05). This increase was evident by a reduction in the difference between the overall percentage of the bulls approved vs the percentage of bulls approved at the first BSE. Furthermore, there was an increase in the percentage of bulls classified as satisfactory potential breeders in the BSE and an evident decrease in the percentage of bulls qualified only for natural breeding service (P < 0.05). In addition, an increase of the scrotal circumference (SC) of the herd was found (P < 0.05). These results indicate the overall quality of the bulls improved over the years. To associate and identify the main sperm abnormalities, 3461 not approved bulls were clustered. The most frequent defects were strongly coiled tail spermatozoa, proximal droplets, and acrosomal defects. Overall, there was no change in the frequency of bulls not approved by the sperm morphology nor the frequency of the main sperm abnormalities over the years. Nevertheless, the frequency of the defects remained very low, implying they were controlled. Additionally, abnormalities in the testis decreased over the years and was associated with the increase in the SC of the herd and a decrease of culled bulls due to low SC. In conclusion, this study demonstrates that there is an association between implementation and use of BSE with improvements in the reproductive quality of future generation bulls. • Records of 20 years and 46,566 BSE from a seedstock herd in Brazil were investigated. • About 14 % of the bulls fail to be approved in the BSE at two years of age. • Semen quality (53 %) & physical defects (47 %) were the most common causes of failure. • Testicular abnormalities decreased, & scrotal circumference increased over the years. • BSE was associated with increased percentage of bulls approved at first BSE over years. [ABSTRACT FROM AUTHOR]

Single Layer Centrifugation (SLC) through a low density colloid offers an alternative solution to antibiotic use in boar semen extenders, with lower costs compared to high density colloids. The aim of this study was to explore the reproductive performance of sows when using SLC-prepared semen doses without antibiotics, employing low density Porcicoll to prepare semen doses for artificial insemination in a commercial swine herd in Thailand. Ejaculates were divided into two equal parts to create insemination doses, with each dose containing 3000 × 106 sperm/80 ml for intra-uterine insemination in individual sows. The sows were inseminated twice, with the interval between the two inseminations ranging from 8 to 16 h. The CONTROL group consisted of 206 semen doses treated with antibiotics, prepared for insemination in 103 sows, while the SLC group comprised 194 SLC-prepared semen doses without antibiotics for inseminating 97 sows. Fertility and fecundity traits, including non-return rate, conception rate, farrowing rate, and litter traits (i.e., the total number of piglets born per litter, number of piglets born alive per litter, number of stillborn piglets, and number of mummified fetuses), were compared between groups. Furthermore, data on piglet characteristics, including live-born and stillborn piglets (i.e., the prevalence of stillbirth (yes, no), birth weight, crown-rump length, body mass index (BMI), and ponderal index (PI)), were determined. No significant differences in non-return rate (75.7 % vs. 77.3 %), conception rate (73.8 % vs. 73.2 %), and farrowing rate (71.8 % vs. 73.2 %) were observed between the CONTROL and SLC groups, respectively (P > 0.05). Nevertheless, the total number of piglets born per litter in the SLC group was higher than in the CONTROL group (14.6 ± 0.9 vs. 12.3 ± 0.6, respectively, P = 0.049). Interestingly, the prevalence of stillbirth in the SLC group was lower than in the CONTROL group (6.2 % vs. 11.6 %, respectively, P < 0.001). Moreover, the newborn piglets in the SLC group exhibited higher birth weight and BMI compared to those in the CONTROL group (1.36 ± 0.03 vs. 1.26 ± 0.02 kg, P = 0.005, and 18.3 ± 0.3 vs. 17.3 ± 0.2 kg/m2, P = 0.003). In conclusion, employing sperm doses after SLC through a low density colloid in artificial insemination within a commercial breeding operation did not have a detrimental impact on either fertility or fecundity traits but showed potential benefits in increasing the total number of piglets born per litter. Moreover, improvements were observed in the birth weight and body indexes of piglets, and the percentage of stillbirths was reduced. Our findings introduce new possibilities for antibiotic alternatives in semen extenders to reduce the risk of antimicrobial resistance in the swine industry. Additionally, they provide compelling reproductive outcomes supporting the integration of SLC-prepared semen doses into artificial insemination practices. • Single Layer Centrifugation is an alternative solution to antibiotic use in boar semen extenders. • Farrowing rate did not differ between control and SLC groups. • The total born in the SLC group was higher than in the control group. • The prevalence of stillbirth in the SLC group was lower than in the control group. • Newborn piglets in the SLC group had higher birth weight and BMI than control group. [ABSTRACT FROM AUTHOR]

Melatonin (MLT) has strong antioxidant capacity and can reduce the damage caused by oxidative stress in sperm, but there is still little content in the field we have studied. In this study, we are committed to scientific research on adding melatonin to Belgian blue bull semen diluent for cryopreservation. Different concentrations (0, 0.1, 0.3, 0.5 or 0.7 mg/mL) of MLT were added diluent. Sperm kinetic parameters, enzyme activity, antioxidant gene expression and fertility were analyzed after thawing. The results showed that MLT concentration of 0.3 mg/mL exerted positive effects on post-thaw kinetic parameters. Compared with other groups, 0.3 mg/mL MLT treated sperm acrosome and plasma membrane integrity, catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) levels significantly increased. Meanwhile, the mRNA expression of antioxidant genes SOD2 , CAT and GPx increased in the 0.3 mg/mL MLT treatment group, and the mRNA expression of apoptosis genes Caspase-3 and Bax were significantly reduced. In addition, in vitro fertilization (IVF) embryo cleavage, blastocyst rate and artificial insemination (AI) pregnancy rate were higher in 0.3 mg/mL MLT. Therefore, MLT showed cryoprotective capacity to the freezing diluent used for Belgian blue bull sperm during the process of freezing-thawing, and the optimal concentration of MLT for the frozen diluent was 0.3 mg/mL. • Optimizing our laboratory's semen diluent formulation by adding MLT. • Belgian blue bulls have good research and production advantages. • Adding 0.3 mg/mL MLT significantly improves bull semen storage efficiency. [ABSTRACT FROM AUTHOR]

Premature ovarian insufficiency (POI) means menopause before 40 years of age affecting about 1 % of women. Approaches based on cell therapy and the paracrine effects of stem cells or bioproducts such as platelet-rich plasma have been proposed, but concerns remain about undesired systemic effects, as well as the need to optimize delivery methods through bioengineering methods. This study explores the efficacy of decellularized bovine ovarian cortex extracellular matrix (OvaECM) hydrogels alone and as a growth factor (GF) carrier (OvaECM+GF) in a chemotherapy-induced POI murine model. In vitro assays showed a gradual release of GF from the OvaECM sustained for two weeks. Chemotherapy drastically reduced follicle numbers, but OvaECM+GF treatment restored pre-antral follicle development. Moreover, this treatment notably regenerated the ovarian microenvironment by increasing cell proliferation and microvessel density while reducing chemotherapy-induced apoptosis and fibrosis. Whole-ovary RNA sequencing and gene set enrichment analysis revealed an upregulation of regeneration-related genes and a downregulation of apoptotic pathways. The OvaECM+GF treatment also yielded significantly better outcomes following ovarian stimulation and in vitro fertilization. After two consecutive crossbreeding cycles, OvaECM+GF-treated mice showed normal reproductive function. This research showcases the biocompatibility and efficacy of OvaECM to reverse POI in mice, setting a foundation to explore innovative bioengineering-based POI therapies. Premature ovarian insufficiency (POI) affects about 1 % of women worldwide, causing early menopause before 40 years old. Current treatments alleviate symptoms but do not restore ovarian function. This study explores an innovative approach using ovarian cortex extracellular matrix hydrogels to deliver growth factors into the murine ovarian niche and reverse POI. In vitro release kinetic assays demonstrated a gradual and sustained release of growth factors. In a POI-induced mouse model, intraovarian injections of the hydrogel encapsulating growth factors restored pre-antral follicle development, increased cell proliferation, reduced apoptosis and fibrosis, and improved ovarian response and in vitro fertilization outcomes. Long-term benefits included larger litter sizes. This innovative technique shows promise in regenerating the ovarian environment and improving reproductive outcomes. [Display omitted] [ABSTRACT FROM AUTHOR]

While uncertainty has been a key explanation for very low fertility throughout Europe, few studies have analysed how macro-level uncertainty trickles down to shape how people think about having children. Most research focuses on economic uncertainty, not political or social uncertainty. We address these gaps with qualitative data from Ukraine, which has experienced extreme political uncertainty and, for the past decade, armed conflict. Ukraine also had exceptionally low fertility, with an estimated total fertility rate of 1.17 in 2021. In July 2021, we conducted 16 online focus groups on topics related to childbearing with informants living in urban and rural areas in Eastern Ukraine, including areas of Donetsk province that were outside Ukrainian government control. Half the groups consisted of persons displaced by the 2014 Donbas war. The discussions revealed distinct patterns whereby experiences of displacement, the simmering armed conflict, and economic problems combined to produce and intensify uncertainties that discouraged couples from having more than one child. Some blamed the government or delved into conspiracy theories. Armed conflict generates its own forms of uncertainty that interact with persistent economic challenges, dampening fertility. [ABSTRACT FROM AUTHOR]

Background. This study is to compare the time to pregnancy (TTP) between patients with endometriosis and nonendometriosis undergoing in vitro fertilisation (IVF).Material and Methods.This is an observational retrospective cohort study. We included 291 patients (53 with endometriosis and 238 without endometriosis) achieving biochemical pregnancy, whether singleton or multifetal (serum beta‐hCG >5 mIU/mL), between 1st January 2014 and 31st March 2020. We excluded patients with incomplete case notes and those declining participation. Time to pregnancy is the interval between the time when infertility was established to the date of confirmed biochemical pregnancy, expressed in months. Endometriosis diagnosis includes any form of endometriosis through surgical confirmation. A statistical analysis was done through the Mann–Whitney U test. Time to pregnancy was assessed through the Kaplan–Meier test. A p value <0.05 is considered statistically significant. Results. Endometriosis patients had a shorter infertility duration (4 years vs. 5 years, p = 0.024). Both groups had similar median age and body mass index at presentation. There was no significant difference in the TTP between endometriosis and nonendometriosis groups (57.7 vs. 70.9 months, p = 0.060), further confirmed by a Cox regression test incorporating confounders (IVF protocol (OR: 1.482, 95% CI 0.667–3.292, and p = 0.334) and type of the cycle (OR 1.071, 95% CI 0.803–1.430, and p = 0.640)). The endometriosis group reached the maximum cumulative pregnancy rate at around 169 months postinfertility diagnosis, whilst the nonendometriosis group at around 255 months postinfertility diagnosis. Conclusion. Time to pregnancy between endometriosis and nonendometriosis is not significantly different. However, infertility among patients with endometriosis tends to be shorter. [ABSTRACT FROM AUTHOR]

The declining fertility rate and increasing marriage age among girls pose challenges for policymakers, leading to issues such as population decline, higher social and economic costs, and reduced labor productivity. Using machine learning (ML) techniques to predict the desire to have children can offer a promising solution to address these challenges. Therefore, this study aimed to predict the childbearing tendency in women on the verge of marriage using ML techniques. Data from 252 participants (203 expressing a "desire to have children" and 49 indicating "reluctance to have children") in Abadan, and Khorramshahr cities (Khuzestan Province, Iran) was analyzed. Seven ML algorithms, including multilayer perceptron (MLP), support vector machine (SVM), logistic regression (LR), random forest (RF), J48 decision tree, Naive Bayes (NB), and K-nearest neighbors (KNN), were employed. The performance of these algorithms was assessed using metrics derived from the confusion matrix. The RF algorithm showed superior performance, with the highest sensitivity (99.5%), specificity (95.6%), and receiver operating characteristic curve (90.1%) values. Meanwhile, MLP emerged as the top-performing algorithm, showcasing the best overall performance in accuracy (77.75%) and precision (81.8%) compared to other algorithms. Factors such as age of marriage, place of residence, and strength of the family center with the birth of a child were the most effective predictors of a woman's desire to have children. Conversely, the number of daughters, the wife's ethnicity, and the spouse's ownership of assets such as cars and houses were among the least important factors in predicting this desire. ML algorithms exhibit excellent predictive capabilities for childbearing tendencies in women on the verge of marriage, highlighting their remarkable effectiveness. This capacity to offer accurate prognoses holds significant promise for advancing research in this field. [ABSTRACT FROM AUTHOR]

Summary First‐generation polyploids often suffer from more meiotic errors and lower fertility than established wild polyploid populations. One such example is the allopolyploid model species Arabidopsis suecica which originated c. 16 000 generations ago. We present here a comparison of meiosis and its outcomes in naturally evolved and first‐generation ‘synthetic’ A. suecica using a combination of cytological and genomic approaches. We show that while meiosis in natural lines is largely diploid‐like, synthetic lines have high levels of meiotic errors including incomplete synapsis and nonhomologous crossover formation. Whole‐genome re‐sequencing of progeny revealed 20‐fold higher levels of homoeologous exchange and eightfold higher aneuploidy originating from synthetic parents. Homoeologous exchanges showed a strong distal bias and occurred predominantly in genes, regularly generating novel protein variants. We also observed that homoeologous exchanges can generate megabase scale INDELs when occurring in regions of inverted synteny. Finally, we observed evidence of sex‐specific differences in adaptation to polyploidy with higher success in reciprocal crosses to natural lines when synthetic plants were used as the female parent. Our results directly link cytological phenotypes in A. suecica with their genomic outcomes, demonstrating that homoeologous crossovers underlie genomic instability in neo‐allopolyploids and are more distally biased than homologous crossovers. [ABSTRACT FROM AUTHOR]

This paper investigates the association between family formation and the labour market trajectories of immigrants' descendants over the life course. Using rich data from the Trajectories and Origins survey from France, we apply multilevel event history models to analyse the transitions in and out of employment for both men and women by parity. We account for unobserved co-determinants of childbearing and employment by applying a simultaneous-equations modelling. Our analysis shows that women's professional careers are negatively associated with childbirth. There are differences across descendant groups. The female descendants of Turkish immigrants are more likely to exit employment and less likely to re-enter employment following childbirth than women from other groups. The negative impact of childbearing on employment is slightly overestimated among women due to unobserved selection effects. Among men, the descendants of European immigrants are less likely to exit employment after having a child than other descendant groups. The study demonstrates the negative effect of childbearing on women's employment, which is pronounced for some minority groups suggesting the need for further policies to help women reconcile work with family life. [ABSTRACT FROM AUTHOR]

Extending lactation length reduces the frequency of critical calving events for the cow and herewith reduces the frequency of periods with increased risk for health problems. Moreover, breeding is postponed until a moment later in lactation, which is associated with better conception rates and less days open after start of the breeding period in most studies. Potential risks of an extended lactation are that milk yield of cows at the end of the lactation may be too low which may lead to cows being overconditioned at the end of the extended lactation. Therefore, extending lactation length might not fit every cow. Individual cow characteristics like parity, milk yield level, or body condition determine the response of the cow to an extended lactation. These individual cow characteristics can be used in customized management strategies to optimize lactation length for individual cows. Customized lactation length for individual cows could limit the impact at herd level of disadvantages concerning milk losses and overconditioning and maintain benefits for improved cow health and fertility, reduced number of surplus calves and increased work satisfaction for the farmer. In conclusion, extending lactation length has interesting perspectives for health and fertility of high‐producing dairy cows, although questions remain concerning management approaches to support lactation persistency of cows with an extended lactation, and consequences for calf health and development. Moreover, ongoing studies aim to develop decision support tools to select individual cows for a specific lactation length. [ABSTRACT FROM AUTHOR]

This article revisits and updates an earlier study of the increased concentration of reproduction that has occurred or is occurring during the fertility transition in developing countries. Using 350 DHS datasets for 87 developing countries, the analysis extends the observation period by several decades, considers a larger range of completed fertility, and expands the geographic coverage by including more countries from all regions of the world. It shows that reproduction tends to become increasingly concentrated within the population during the early stages of the fertility transition in developing countries, but that once completed fertility reaches a level of about 4 children per woman, the concentration of reproduction tends to stabilize. The changing concentration of reproduction over the course of the fertility transition in developing countries has implications for who becomes a parent, who bears the risks of childbearing, and who covers the costs of raising children in a society. [ABSTRACT FROM AUTHOR]

Commercial livestock producers need to prioritize genetic progress for health and efficiency traits to address productivity, welfare, and environmental concerns but face challenges due to limited pedigree information in extensive multi‐sire breeding scenarios. Utilizing pooled DNA for genotyping and integrating seminal microbiome information into genomic models could enhance predictions of male fertility traits, thus addressing complexities in reproductive performance and inbreeding effects. Using the Angus Australia database comprising genotypes and pedigree data for 78,555 animals, we simulated percentage of normal sperm (PNS) and prolificacy of sires, resulting in 713 sires and 27,557 progeny in the final dataset. Publicly available microbiome data from 45 bulls was used to simulate data for the 713 sires. By incorporating both genomic and microbiome information our models were able to explain a larger proportion of phenotypic variation in both PNS (0.94) and prolificacy (0.56) compared to models using a single data source (e.g., 0.36 and 0.41, respectively, using only genomic information). Additionally, models containing both genomic and microbiome data revealed larger phenotypic differences between animals in the top and bottom quartile of predictions, indicating potential for improved productivity and sustainability in livestock farming systems. Inbreeding depression was observed to affect fertility traits, which makes the incorporation of microbiome information on the prediction of fertility traits even more actionable. Crucially, our inferences demonstrate the potential of the semen microbiome to contribute to the improvement of fertility traits in cattle and pave the way for the development of targeted microbiome interventions to improve reproductive performance in livestock. [ABSTRACT FROM AUTHOR]

Azoospermia (the complete absence of spermatozoa in the semen) is a common cause of male infertility. The etiology of azoospermia is poorly understood. Whole-genome analysis of azoospermic men has identified a number of candidate genes, such as the X-linked testis-expressed 11 (TEX11) gene. Using a comparative genomic hybridization array, an exonic deletion (exons 10–12) of TEX11 had previously been identified in two non-apparent azoospermic patients. However, the putative impact of this genetic alteration on spermatogenesis and the azoospermia phenotype had not been validated functionally. We therefore used a CRISPR/Cas9 system to generate a mouse model (Tex11Ex9-11del/Y) with a partial TEX11 deletion that mimicked the human mutation. Surprisingly, the mutant male Tex11Ex9-11del/Y mice were fertile. The sperm concentration, motility, and morphology were normal. Similarly, the mutant mouse line's testis transcriptome was normal, and the expression of spermatogenesis genes was not altered. These results suggest that the mouse equivalent of the partial deletion observed in two infertile male with azoospermia has no impact on spermatogenesis or fertility in mice, at least of a FVB/N genetic background and until 10 months of age. Mimicking a human mutation does not necessarily lead to the same human phenotype in mice, highlighting significant differences species. [ABSTRACT FROM AUTHOR]

Introduction: High testosterone levels might be associated with coarser fiber in alpacas, a [ABSTRACT FROM AUTHOR]

There is a lack of understanding of the persistence of elevated teen fertility rates in certain regions and countries, in contrast to the significant decline observed in other regions globally. This report considers fertility trends among 15‐ to 19‐year olds in the period 1950–2020 and explores potential driving factors behind the significant shifts that occurred over this period. The countries where teen fertility remains high are those with fast‐growing populations, primarily located in sub‐Saharan Africa. Countries with higher teen fertility are typically characterized by limited use of modern contraception, lower education levels, and early marriage. Sub‐Saharan Africa has emerged as the world region with the most teen births, increasing its proportion of global teen births from 12 percent in 1950 to 47 percent in 2020, a time during which this region's share of the global adolescent (15–19) population grew from 7.5 percent to 19 percent. By 2035, 67 percent of all teen births globally are projected to occur in this region. Consequently, the future number of births to teenage mothers will to a large extent depend on the development in sub‐Saharan Africa over the coming decades. [ABSTRACT FROM AUTHOR]

The desire to avoid pregnancy—to delay the next birth or have no further births—is a fundamental sexual and reproductive health indicator. We show that two readily available measures—prospective fertility preferences and the demand for contraception [Demand] construct—provide substantially different portraits of historical trends. They also yield correspondingly different assessments of the sources of contraceptive change. We argue, with supporting empirical evidence, that Demand enormously overstates the historical trend in the desire to avoid pregnancy because Demand as currently constructed is in part a function of contraceptive prevalence. This makes for "reverse causality" in decompositions of contraceptive change, producing an upward distortion on the order of 25 percentage points in the amount of contraceptive change attributed to a change in fertility desires. Decomposition of contraception change free of the distortion reveals that contraceptive change has been due almost entirely to more complete implementation of fertility preferences. This is explained in part by the surprisingly slight historical change in preferences, a fact we document and then show is a consequence of a historical shift in parity composition toward lower parities. [ABSTRACT FROM AUTHOR]

STUDY QUESTION What is the impact of co-designed, evidence-based information regarding the anti-Mullerian hormone (AMH) test on women's interest in having the test? SUMMARY ANSWER Women who viewed the evidence-based information about the AMH test had lower interest in having an AMH test than women who viewed information produced by an online company selling the test direct-to-consumers. WHAT IS KNOWN ALREADY Online information about AMH testing often has unfounded claims about its ability to predict fertility and conception, and evidence suggests that women seek out and are recommended the AMH test as a measure of their fertility potential. STUDY DESIGN, SIZE, DURATION An online randomized trial was conducted from November to December 2022. Women were randomized (double-blind, equal allocation) to view one of two types of information: co-designed, evidence-based information about the AMH test (intervention), or existing information about the AMH test from a website which markets the test direct-to-consumers (control). A total of 967 women were included in the final analysis. PARTICIPANTS/MATERIALS, SETTING, METHODS Participants were women recruited through an online panel, who were aged 25–40 years, living in Australia or The Netherlands, had never given birth, were not currently pregnant but would like to have a child now or in the future, and had never had an AMH test. The primary outcome was interest in having an AMH test (seven-point scale; 1 = definitely NOT interested to 7 = definitely interested). Secondary outcomes included attitudes, knowledge, and psychosocial and behavioural outcomes relating to AMH testing. MAIN RESULTS AND THE ROLE OF CHANCE Women who viewed the evidence-based information about the AMH test had lower interest in having an AMH test (MD = 1.05, 95% CI = 0.83–1.30), less positive attitudes towards (MD = 1.29, 95% CI = 4.57–5.70), and higher knowledge about the test than women who viewed the control information (MD = 0.75, 95% CI = 0.71–0.82). LIMITATIONS, REASONS FOR CAUTION The sample was more highly educated than the broader Australian and Dutch populations and some measures (e.g. influence on family planning) were hypothetical in nature. WIDER IMPLICATIONS OF THE FINDINGS Women have higher knowledge of and lower interest in having the AMH test when given evidence-based information about the test and its limitations. Despite previous studies suggesting women are enthusiastic about AMH testing to learn about their fertility potential, we demonstrate that this enthusiasm does not hold when they are informed about the test's limitations. STUDY FUNDING/COMPETING INTEREST(S) This project was supported by an NHMRC Emerging Leader Research Fellowship (2009419) and the Australian Health Research Alliance's Women's Health Research, Translation and Impact Network EMCR award. B.W.M. reports consultancy for ObsEva and Merck and travel support from Merck. D.L. is the Medical Director of, and holds stock in, City Fertility NSW and reports consultancy for Organon and honoraria from Ferring, Besins, and Merck. K.H. reports consultancy and travel support from Merck and Organon. K.M. is a director of Health Literacy Solutions that owns a licence of the Sydney Health Literacy Lab Health Literacy Editor. No other relevant disclosures exist. TRIAL REGISTRATION NUMBER ACTRN12622001136796. TRIAL REGISTRATION DATE 17 August 2022. DATE OF FIRST PATIENT'S ENROLMENT 21 November 2022. [ABSTRACT FROM AUTHOR]

Objective: The aim of the current study was to assess the effects of Nigella sativa essential oil on testicular toxicity in mice induced by dexamethasone. Materials and Methods: Forty NMRI mice were randomly divided into four groups. The first group (Sham) received 1 ml per day of normal saline by intraperitoneal (i.p.) injection for 7 days. The second group (Control) received (i.p) injection of 5 mg/kg dexamethasone for 7 days. The third group (Dexa+ N.S 5 mg/kg) received dexamethasone (5 mg/kg) and gavaged 5 mg/kg N. sativa essential oil for 7 days. The fourth group (N.S 5 mg/kg) for 7 days was gavaged 5 mg/kg N. sativa. Histopathology of testis, spermatogenesis, and sperm fertility rate were assessed. Results: The results of histopathology assessments showed that in the third group, all histopathology criteria were decreased compared to the second group. The number of seminiferous tubules that had abnormal spermatogenesis in Johnsen’s score was slightly decreased in the third group compared to the second group. Furthermore, in the third group, embryo formation criteria were increased. Conclusion: The data of this research demonstrate that N. sativa improves spermatogenesis defects and sperm fertility in mice treated with dexamethasone. [ABSTRACT FROM AUTHOR]

Introduction: Alcohol consumption is associated with unintended pregnancies among teenagers. Its role as a broader determinant of teenage fertility rates remains unclear. We investigate whether adolescent binge drinking affects the number of teenage births. Methods: Binge drinking data from 137,898 females aged 15–16 were collected in the HBSC study (2002–2018, 43 countries/regions) and 267,359 in the ESPAD study (1995–2019, 41 countries/regions). Age‐specific fertility rates were from the Human Fertility Database and the World Health Organization. We examined changes over time in countries' average levels of binge drinking among female pupils aged 15–16 and population‐level fertility rates for the same cohorts when aged 16–19 years. Results: Controlling for differences between countries and survey waves, we found an association between binge drinking and fertility rate, B = 0.019, 95% confidence interval [0.004, 0.034]. When accounting for the countries' time trends, the association was substantially reduced, B = 0.006, 95% confidence interval [−0.0062, 0.0174]. The relationship was not moderated by abortion rates and controlling for contraceptive use had no impact on the findings. Discussion and Conclusions: The association between adolescent binge drinking and fertility rates diminishes when accounting for country‐specific time trends. Given the lack of clear mechanisms linking binge drinking to trends in fertility rates rather than shorter‐term changes, the association likely reflects broader secular trends. Binge drinking may be involved in teen pregnancy and childbirth in individual cases but it does not explain recent developments in teenage fertility rates. [ABSTRACT FROM AUTHOR]

Objective: To determine and compare pregnancy outcomes after bilateral uterine artery ligation (BUAL) or bilateral hypogastric artery ligation (BHAL) for postpartum hemorrhage (PPH). Material and Methods: This retrospective cross-sectional study was conducted from January 2010 to June 2018 at a tertiary referral hospital. Patients who had undergone arterial ligation for PPH were included in the study. Patients who had undergone BUAL and BHAL were compared with a control group in terms of fertility and pregnancy outcomes. Results: A total of 156 patients were included, of whom 47 underwent BUAl, 59 underwent BHAL and 50 were in the control group. There was no significant difference between the groups in subsequent pregnancies in terms of the incidence of miscarriage, fetal growth restriction, preeclampsia, primary cesarean deliveries, and infertility (p>0.05). There was a significant difference between all groups in gestational age at birth and birthweight. Preterm birth was observed in 32.2% of patients in the BHAL group, and this rate was significantly higher than in the BUAL (12.8%) and control (6%) groups (p=0.001). Conclusion: PPH is a life-threatening obstetric problem. The effects of interventions performed to reduce pelvic blood flow in patients may lead to persistent problems, such as preterm birth and low birth weight in the next pregnancy. However, these interventions do not appear to affect the risk of miscarriage. In subsequent pregnancies of patients who received BHAL, special attention should be paid to preterm birth. [ABSTRACT FROM AUTHOR]

Methodological limitations in studying the association between the use of fertility drugs and cancer include the inherent increased risk of cancer in women who never conceive, the increased risk of cancer because of factors (endometriosis and unopposed estrogen) associated with infertility, the low incidence of most of these cancers, and that the diagnosis of cancer is typically several years after fertility drug use. On the basis of available data, there does not appear to be an association between fertility drugs and breast, colon, or cervical cancer. There is no conclusive evidence that fertility drugs increase the risk of uterine cancer, although women with infertility are at higher risk of uterine cancer. There are insufficient data to comment on the risk of melanoma and non-Hodgkin lymphoma associated with fertility drug use. Women should be informed that there may be an increased risk of invasive and borderline ovarian cancers and thyroid cancer associated with fertility treatment. It is difficult to determine whether this risk is related to underlying endometriosis, female infertility, or nulliparity. [ABSTRACT FROM AUTHOR]

We investigate natural selection on polygenic scores in the contemporary US, using the Health and Retirement Study. Across three generations, scores which correlate negatively (positively) with education are selected for (against). However, results only partially support the economic theory of fertility as an explanation for natural selection. The theory predicts that selection coefficients should be stronger among low-income, less educated, unmarried and younger parents, but these predictions are only half borne out: coefficients are larger only among low-income parents and unmarried parents. We also estimate effect sizes corrected for noise in the polygenic scores. Selection for some health traits is similar in magnitude to that for cognitive traits. [ABSTRACT FROM AUTHOR]

Background: Knowledge about fertility and factors affecting it, for example, the impact of age, seem to be lacking, even in highly educated populations. The same applies to fertility preservation knowledge, pointing to the relevance of increasing fertility preservation awareness and education among young women. Objective: To describe general fertility knowledge and factors affecting fertility, fertility preservation knowledge and attitudes, and the desire to access more information on this topic in a sample of reproductive-age Portuguese women. Methods: The sample comprised 257 Portuguese women aged 18–45, mostly single and nulliparous. A questionnaire was developed explicitly for this study and disseminated through social media advertisements. Results: Career building/development and financial stability were the more endorsed options for delaying childbearing, with 90 (35%) and 68 (26.5%), respectively. Most participants considered becoming a mother important (n = 185; 72%). More than halve provided an incorrect answer regarding the age range of women being more fertile (n = 132; 51.4%) and the age range of fertility decline (n = 168; 65.4%). Participants were aware of the influence of lifestyle and sexual health factors as well as the effect of age. Oocytes cryopreservation was the technique participants knew more (n = 206; 80.1%), but 177 (68.9%) showed no interest in using it. Most participants agreed that fertility and fertility preservation information should be provided during medical consultations or at school. Conclusions: More information regarding fertility and fertility preservation is relevant to ensure that more women can make informed decisions concerning their reproductive life. [ABSTRACT FROM AUTHOR]

The increased proportion of youth aged 15–24 or 15–29 in total or adult population has long been shown to influence the intensity of sociopolitical destabilisation in general and political violence in particular. Youth bulges played an important role in the destabilising processes of the Arab Spring. We show that the influence of youth bulges in Egypt (and North Africa in general) is far from being limited to historical events. The demographic dynamics of Egypt (and a number of other North African countries) implies the emergence of new youth bulges in the future. We proceed to discuss this phenomenon and its sociopolitical implications. The period of the eve of the Arab Spring and the beginning of the 2010s was accompanied by the strengthening of the influence of Islamists in all countries of North Africa and in many Arab countries of Asia, which was likely associated with a period of significant growth of fertility rates in these countries. This surge in fertility rates generated those youth bulges that are confidently forecasted in these countries for the 2030s. It cannot be ruled out that in the 2030s Egypt (and North Africa in general) will experience a new destabilisation wave, which will be a kind of echo of the wave of the late 2000s – early 2010s. [ABSTRACT FROM AUTHOR]

Background: Infertility affects 186 million people worldwide, with male factors contributing to 50% of infertility cases. Semen analysis is a key for diagnosing male factor infertility, but sperm parameters can be influenced by ejaculatory abstinence (EA) duration. Shortening or prolonging EA can impact on semen quality and assisted reproductive technology (ART) outcomes, but the optimal EA duration remains unclear, particularly for infertility patients. Objectives: This study conducts a comprehensive meta‐analysis to explore the impact of varying abstinence durations on semen quality and fertility outcomes. Methods: Three English database (PubMed, Embase, and Cochrane Central Register of Controlled Trials) as well as four Chinese database (China National Knowledge Infrastructure, Chinese Scientific Journals database, WanFang database, and Chinese Biomedical Literature database) were searched from 2000 to August 2023. The classical meta‐analysis and "one‐stage" dose–response meta‐analysis were conducted to compare the associations of different abstinence durations (short‐term abstinence vs. long‐term abstinence) on semen quality in healthy adult and different type of infertile patients. Results: There were 85 eligible studies were finally included. The meta‐analysis of volume (mean difference [MD] = −0.95 mL, 95% confidence interval [CI]: −1.16 to −0.74 mL), total sperm count (TSC) (MD = −102.45×106, 95% CI: −117.98×106 to −86.91×106), sperm concentration (SC) (MD = −11.88×106/mL, 95% CI: −18.96×106/mL to −4.80×106/mL), DNA fragmentation index (DFI) (MD = −2.37%, 95% CI: −4.73% to −0.01%) in healthy men showed a significant decrease with different abstinence durations (short‐term abstinence vs. long‐term abstinence). The meta‐analysis of infertile men showed significant decrease in volume in various subgroups (MD range: −0.73 to −1.17 mL) with P < 0.01; TSC (MD = −61.93×106, 95% CI: −88.84×106 to −35.01×106), SC (MD = −5.39×106/mL, 95% CI: −9.97×106 to −0.81×106/mL), DFI (MD = −5.63%, 95% CI: −10.19% to −1.06%) in unexplained infertility subgroup; significant increase in viability (MD = 6.14%, 95% CI: 3.61% to 8.68%) in the unexplained infertility subgroup. The dose–response meta‐analysis showed that TSC in oligozoospermia showed a nonlinear increase (coefficient from 3.38 to −5.76, P from 0.02 to 0.22) and the truncation point was around the 4th to 5th abstinence day. The percentage of progressive motile sperm (PR) in asthenozoospermia showed a significant decrease (coefficient = −2.39, 95% CI: −4.28 to −0.50). For fertility outcomes of different ARTs, only the clinical pregnancy rate (CPR) in the intrauterine insemination (IUI) subgroup showed a significant decrease around the 3rd day (coefficient = 0.85, 95% CI: 0.75 to 0.97). Conclusions: Short‐term abstinence may be associated with limited improvements in semen quality in healthy men but could be more beneficial for infertile men, especially within the first 4 days of abstinence. Caution is urged in making definitive conclusions about the causal relationship between abstinence time and semen quality changes due to potential confounding and interactions. [ABSTRACT FROM AUTHOR]

Introduction: Treatments against urogenital cancers frequently have fertility side‐effects. The strategy to preserve fertility after oncologic treatments is still a matter of debate with a lack of evidence and international guidelines. The aim of this study is to investigate fertility preservation practices before urogenital cancer treatments and to compare national habits. Material and methods: An online anonymous survey was submitted from January to June 2021 to six European urological societies. The 31‐items questionnaire included questions about demography, habits of evaluation, and management of fertility preservation in case of urogenital cancer treatments. Results: Two hundred twenty‐eight urologists from six urological societies in five different countries (Belgium, The Netherlands, Luxembourg, France, Finland) filled out the survey. Three quarter (74%; n = 166) usually propose a cryopreservation before orchidectomy. In case of oligo/azoo‐spermia, the technique performed for the sperm extraction during orchidectomy varies among the sample: 70.5% (n = 160) of the responders do not perform a Testicular Sperm Extraction (TESE) nor a Percutaneous Epididymal Sperm Aspiration (PESA). The cryopreservation for prostate cancer treatments is never proposed in 48.17% (n = 105) of responders but conversely it is always proposed in 5.05% (n = 11). The cryopreservation before bladder cancer treatments is not commonly proposed (67.5%, n = 154). Conclusion: Our study showed variable country specific tendencies in terms of fertility preservation in the period of treatment of urological cancers. These differences seem to be related to national guidelines recommendations. Standardization of international guidelines is urgently needed in the field of fertility for urological cancer patients. [ABSTRACT FROM AUTHOR]

There is a high prevalence of adolescent girls with ovulatory menstrual (OM) dysfunction, which is associated with school absenteeism and mental health challenges. Low menstrual health literacy among this group has evoked calls to review OM health education. This qualitative study sought to explore gaps in current OM health education and to validate a holistic school-based OM health literacy program named My Vital Cycles®. Findings are based on 19 written reflections, six focus group discussions and three interviews conducted with 28 girls aged 14–18 years from 11 schools, and five mothers. Six themes compared current OM health education with My Vital Cycles®: understating health, comprehensiveness, resources, teaching, parents and cycle tracking. Future refinements to the program comprised: inclusion of the complete reproductive lifespan, use of visual media and developing a mobile application. These findings inform future research in a whole school approach, strengths-based teaching and changes in the health curriculum. [ABSTRACT FROM AUTHOR]

Introduction: Fertility after cancer is a top concern for adolescents and young adults with cancer (AYAs) (15–39 years old at diagnosis). The authors characterized live births after cancer by race and ethnicity ("race/ethnicity") in a population‐based sample of female AYAs. Methods: This study used Texas Cancer Registry data linked to birth certificates (1995–2016) to estimate cumulative incidence of live birth, based on first live birth after cancer, and compared differences by race/ethnicity. Proportional subdistribution hazards models were used to estimate associations between race/ethnicity and live birth, adjusted for diagnosis age, cancer type, stage, year, and prior live birth, overall and for each cancer type. Results: Among 65,804 AYAs, 10‐year cumulative incidence of live birth was lower among non‐Hispanic Black AYAs than other racial/ethnic groups: 10.2% (95% confidence interval [CI], 9.4–10.9) compared to 15.9% (95% CI, 14.1–17.9) among Asian or Pacific Islander, 14.7% (95% CI, 14.2–15.3) among Hispanic, and 15.2% (95% CI, 14.8–15.6) among non‐Hispanic White AYAs (p <.01). In the adjusted overall model, Black AYAs were less likely to have a live birth after cancer than all other groups. In adjusted models for each cancer type, live birth was significantly less likely for Black AYAs with gynecologic cancers or lymphomas (compared to White AYAs) or thyroid cancers (compared to Hispanic AYAs). Conclusion: Black AYAs are less likely than AYAs of other races/ethnicities to have a live birth after cancer, in contrast to patterns of live birth in the general population. Research and action to promote childbearing equity after cancer are imperative. The authors used Texas Cancer Registry data linked to live birth certificates (1995–2016) to characterize live births after cancer by race and ethnicity ("race/ethnicity") among females diagnosed with cancer as adolescents and young adults (AYAs) (15–39 years old at diagnosis). Overall and within certain cancer types, Black AYAs were less likely than AYAs of other races or ethnicities to have a live birth after cancer, in contrast to general population birth patterns. [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. The objective of this prospective cohort study was to determine if progesterone (P4) profiles differed between dairy cows with or without inflammatory disorders early postpartum. A total of 708 cows from 2 commercial herds were enrolled 3 wk before parturition and examined for clinical health disorders (difficult calving, retained placenta, metritis, displaced abomasum, mastitis, or lameness) until 5 wk postpartum. Serum haptoglobin (Hp) was measured in blood at 2 and 6 DIM (range ±2 d); metritis was assessed at 4, 8, 11, and 15 DIM; and purulent vaginal discharge and endometritis (≥6% PMN in endometrial cytology sampled by cytobrush) were assessed at 35 ± 3 DIM. As Hp ≥0.8 g/L or endometritis were associated with ovarian dysfunction in previous studies, cows with serum Hp ≥0.8 g/L at either time point and endometritis, regardless of clinical disease, were classified as the cohort with inflammatory disorders (INFLAM; n = 139). Clinically healthy cows without difficult calving, with singleton birth, with Hp <0.8 g/L at both sampling times, without endometritis or purulent vaginal discharge, and BCS ≥3.00 (1 to 5 scale) were classified as healthy (n = 133). Cows with only one of the 2 conditions (high Hp or endometritis) were excluded. Cohorts had serum P4 measured twice weekly from 35 to 70 DIM (±3 d), and the first detected luteal phase (LP) during the sampling period was defined as the period from onset of luteal activity (P4 increase to ≥1 ng/mL) until decline of P4 to <1 ng/mL. The odds of prolonged LP (≥21 d long), average LP length, peak P4, and time to P4 decline (hazard rate) were analyzed using multivariable mixed logistic, linear, or Cox proportional hazard regression models including INFLAM status, parity, sampling day (when applicable), and herd as a random effect considering the covariates of season, milk yield at first DHIA test, and DIM at onset of cyclicity or LP length (when applicable). Cows with INFLAM had greater odds of prolonged LP (LSM ± SEM; 67% vs. 37% ± 7%), greater average LP length (17 vs. 15 ± 2 d), lesser P4 at d 4 (4.6 vs. 5.5 ± 0.3 ng/mL) and d 7 (6.0 vs. 7.7 ± 0.3 ng/mL) of the LP, and lesser peak P4 (6.9 vs. 8.2 ± 0.3 ng/mL) during the LP than healthy cows. Status of INFLAM was associated with time to P4 decline in multiparous but not primiparous cows; the LP of INFLAM multiparous cows was less likely to have luteolysis (P4 decline) by d 14 (adjusted hazard ratio [AHR] and 95% CI: 0.54; 0.31 to 0.94) or by d 21 (AHR: 0.32; 0.12 to 0.84) than in healthy multiparous cows. In conclusion, postpartum cows with markers of systemic inflammation at wk 1 and uterine inflammation at wk 5 had altered luteal function (prolonged LP and lower P4 concentrations) before first breeding, which is a possible pathway linking postpartum health disorders and reduced fertility. [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. Our objectives were to evaluate the endometrial responsiveness of dairy heifers to an intrauterine infusion of recombinant bovine interferon-tau (rbIFN-τ) and to associate endometrial responses to rbIFN-τ with subsequent reproductive performance. In experiments 1 and 2, cyclic heifers were enrolled in a program for synchronization of the estrous cycle, and blood sampling and ultrasonography examinations were performed on d 0, 4, 7, 11, and 14 of the estrous cycle. In experiment 1, heifers were randomly assigned to receive an intrauterine infusion containing 2 µg of rbIFN-τ (rbIFN-τ = 19) or saline control (CTRL = 19) into the uterine horn ipsilateral to the corpus luteum (CL) on d 14 of the estrous cycle. Then, 6 hours after the infusion, the infused uterine horn was flushed for sampling of the uterine luminal fluid (ULF) for composition analysis, and the endometrium was biopsied for transcriptomics. In experiment 2, 100 heifers received an intrauterine infusion of rbIFN-τ, and the same procedures for uterine sample collection were performed as described in experiment 1. After the intrauterine test, heifers were enrolled in a breeding program and classified as highly fertile (HF; pregnant at first AI) or subfertile (SF; not pregnant at first AI). Statistical analyses were performed using regression models, which included the effects of treatment (experiment 1: CTRL vs. rbIFN-τ) or fertility group (experiment 2: HF vs. SF) and block of samples. Intrauterine infusion of rbIFN-τ increased the expression of classical interferon-stimulated genes in the endometrium (e.g., ISG15, MX1, OAS2, IRF9 , and USP18), and an antiviral response was predicted to be the main downstream effect of the transcriptome changes. In addition, rbIFN-τ increased the abundance of cholesterol, glycerol, and the overall concentration of oxylipins in the ULF. Analysis of endometrial transcriptome between HF and SF heifers revealed important differences in the expression of genes associated with cell signaling, metabolism, attachment, and migration, with a large representation of genes encoding extracellular matrix proteins. In general, differentially expressed genes were expected to be downregulated by IFN-τ but seemed to fail to be downregulated in SF heifers, resulting in higher expression in SF compared with HF heifers. Subfertile heifers had lower concentrations of glycerol and an altered profile of oxylipins in the ULF, with a lower abundance of oxylipins derived from arachidonic acid and dihomo-γ-linolenic acid, and a greater abundance of oxylipins derived from linoleic acid. Measurements of ovarian function did not differ between groups and, therefore, did not influence the observed results in uterine biology. Overall, the endometrial responsiveness to IFN-τ is variable among individuals and associated with subsequent fertility of heifers, indicating that communication between conceptus and endometrium is critical for the uterine receptivity and survival of pregnancy. [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. The objectives of this prospective cohort study were to characterize associations among genomic merit for fertility with ovarian and endocrine function and the estrous behavior of dairy cows during an entire nonhormonally manipulated estrous cycle. Lactating Holstein cows entering their first (n = 82) or second (n = 37) lactation had ear-notch tissue samples collected for genotyping using a commercial genomic test. Based on genomic predicted transmitting ability values for daughter pregnancy rate (gDPR), cows were classified into high (Hi-Fert; gDPR > 0.6, n = 36), medium (Med-Fert; gDPR −1.3 to 0.6, n = 45), and low fertility (Lo-Fert; gDPR < −1.3, n = 38) groups. At 33 to 39 DIM, cohorts of cows were enrolled in the Presynch-Ovsynch protocol for synchronization of ovulation and initiation of a new estrous cycle. Thereafter, the ovarian function and endocrine dynamics were monitored daily until the next ovulation by transrectal ultrasonography and concentrations of progesterone (P4), estradiol, and FSH. Estrous behavior was monitored with an ear-attached automated estrus detection system that recorded physical activity and rumination time. Overall, we observed an association between fertility group and the ovarian and hormonal phenotype of dairy cows during the estrous cycle. Cows in the Hi-Fert group had greater circulating concentrations of P4 than cows in the Lo-Fert group from d 4 to 13 after induction of ovulation and from day −3 to −1 before the onset of luteolysis. The frequency of atypical estrous cycles was 3-fold greater for cows in the Lo-Fert than the Hi-Fert group. We also observed other modest associations between genomic merit for fertility with the follicular dynamics and estrous behavior. We found several associations between milk yield and parity with ovarian, endocrine, and estrous behavior phenotypes as cows with greater milk yield and in the second lactation were more likely to have unfavorable phenotypes. These results demonstrate that differences in reproductive performance between cows of different genomic merit for fertility classified based on gDPR may be partially associated with circulating concentrations of P4, the incidence of atypical phenotypes during the estrous cycles, and, to a lesser extent, the follicular wave dynamics. The observed physiological and endocrine phenotypes might help explain part of the differences in reproductive performance between cows of superior and inferior genomic merit for fertility. [ABSTRACT FROM AUTHOR]