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Objective: To investigate the role of maternal night shift work in occurrence of urogenital anomalies in offspring, considering a possible interaction with mode of conception.Methods: A population-based cohort comprising births in South Australia (1986-2002) was produced via linkage of fertility clinic records, perinatal and birth defects data. This study concerned first births to women in paid employment (n=98 103). Potential exposure to night shift was imputed by applying a job-exposure matrix to recorded occupation. Associations were examined using logistic regression, first for nurses and other night shift workers separately, then combined. An interaction term for night shift work and mode of conception was included in all models, while adjusting for covariates.Results: Associations were similar for nurses and other night shift workers, although only statistically significant for the former when considered separately. A multiplicative interaction was supported: for natural conceptions, maternal night shift work was not associated with offspring urogenital anomalies (OR=0.99, 95% CI 0.84 to 1.15); where a birth arose from fertility treatment, urogenital anomalies were significantly higher among births to all night shift workers compared with day workers (OR=2.07, 95% CI 1.20 to 3.55). This was not due to differences in the type of fertility treatment received.Conclusions: Women in occupations that probably involved night shift did not have offspring with increased prevalence of urogenital anomalies if they conceived naturally. When night shift workers conceived with fertility treatment, the prevalence of urogenital anomalies was elevated. Possibly these women had the greatest exposure to night shift work, or least tolerance for this work schedule, or heightened sensitivity to hormonal aspects of fertility treatment. [ABSTRACT FROM AUTHOR]

Study Question: Does fertility treatment influence cognitive ability in school aged children, and does the impact vary with the type of treatment?Summary Answer: The available high-quality evidence indicates that specific treatments may give rise to different effects on cognitive development, with certain treatments, including ICSI, associated with cognitive impairment.What Is Known Already: Previous reviews of the literature concerning cognitive outcomes among children conceived with medical assistance have concluded that study findings are generally 'reassuring', but limited attention has been paid to the quality of this research. In addition, no review has separately assessed the range of treatment modalities available, which vary in invasiveness, and thus, potentially, in their effects on developmental outcomes.Study Design, Size, Duration: A systematic review was undertaken. We searched PubMed, PsycINFO and the Educational Resources Information Centre database to identify English-language studies published up until 21 November 2016.Participants/materials, Setting, Methods: Two authors independently reviewed identified articles, extracted data and assessed study quality. Studies were eligible if they assessed cognitive development from age 4 years or more, among children conceived with fertility treatment compared with either children conceived naturally or children born from a different type of fertility treatment. Where available, data were extracted and reported separately according to the various components of treatment (e.g. mode of fertilization, embryo freezing, etc.). Risk of bias was assessed using the Newcastle-Ottawa Scale, with a score ≥7/9 indicative of high quality.Main Results and the Role Of Chance: The search identified 861 articles, of which 35 were included. Of these, seven were rated high quality. Most studies (n = 22) were subject to selection bias, due to the exclusion of children at increased risk of cognitive impairment. Among high-quality studies, there was no difference in cognitive outcomes among children conceived with conventional IVF and those conceived naturally. Findings among high-quality studies of children conceived with ICSI were inconsistent: when compared with children conceived naturally, one study reported lower intelligence quotient (IQ; 5-7 points, on average) among ICSI children whereas the remaining two high-quality studies reported no difference between groups. Furthermore, among the three high-quality studies comparing children conceived with ICSI compared with conventional IVF, one reported a significant increase in the risk of mental retardation, one reported a small difference in IQ (3 points lower, on average) and one no difference at all. There were scant studies examining exposure to embryo freezing, or less invasive treatments such as ovulation induction without IVF/ICSI.Limitation, Reasons For Caution: Most existing studies had methodological limitations including selection bias and/or failure to address confounding by family background. In addition, a meta-analysis could not be performed due to heterogeneity in the assessment of cognitive outcomes. These factors impeded our ability to synthesize the evidence and draw reliable conclusions.Wider Implications Of the Findings: The conflicting findings among studies of children conceived with ICSI require clarification, in light of the increasing use of this technique for reasons other than male-factor infertility. Further population-based studies are needed that utilize contemporary data to examine specific aspects of treatment and combinations of techniques (e.g. ICSI with frozen embryo cycles). Importantly, studies should include the complete group of children exposed to treatment.Study Funding/competing Interest(s): A.R.R. is supported by a Career Development Fellowship from the National Health and Medical Research Council of Australia. L.J.M. is funded by a fellowship from the Heart Foundation of Australia. The authors declare there are no competing interests.Trial Registration Number: Not applicable. [ABSTRACT FROM AUTHOR]

Background: Fertility treatment is associated with increased risk of major birth defects, which varies between in vitro fertilisation (IVF) and intracytoplasmic sperm injection (ICSI), and is significantly reduced by embryo freezing. We therefore examined a range of additional perinatal outcomes for these exposures. Methods: All patients in South Australia receiving assisted conception between Jan 1986–Dec 2002 were linked to the state-wide perinatal collection (all births/stillbirths ≥20 weeks gestation or 400 g birth weight, n = 306 995). We examined stillbirth, mean birth weight, low birth weight (<2500 g, <1500 g), small size for gestational age (<10th percentile, <3rd percentile), large size for gestational age (>90th percentile), preterm birth (32–<37 weeks, <32 weeks gestation), postterm birth (≥41 weeks gestation), Apgar <7 at 5 minutes and neonatal death. Results: Relative to spontaneous conceptions, singletons from assisted conception were more likely to be stillborn (OR = 1.82, 95% Confidence Interval (CI) 1.34–2.48), while survivors as a group were comprehensively disadvantaged at birth, including lower birth weight (−109 g, CI −129–−89), very low birth weight (OR = 2.74, CI 2.19–3.43), very preterm birth (OR = 2.30, CI 1.82–2.90) and neonatal death (OR = 2.04, CI 1.27–3.26). Outcomes varied by type of assisted conception. Very low and low birth weight, very preterm and preterm birth, and neonatal death were markedly more common in singleton births from IVF and to a lesser degree, in births from ICSI. Using frozen-embryos eliminated all significant adverse outcomes associated with ICSI but not with IVF. However, frozen-embryo cycles were also associated with increased risk of macrosomia for IVF and ICSI singletons (OR = 1.36, CI 1.02–1.82; OR = 1.55, CI 1.05–2.28). Infertility status without treatment was also associated with adverse outcomes. Conclusions: Births after assisted conception show an extensive range of compromised outcomes that vary by treatment modality, that are substantially reduced after embryo freezing, but which co-occur with an increased risk of macrosomia. [ABSTRACT FROM AUTHOR]

BACKGROUND In Australia, fertility treatment is partly or wholly reimbursable under federal benefits schemes, without restrictions on age, number of treatment cycles or existing family size. In this study, we aimed to characterize the potential need for and use of fertility treatments in a population-based cohort of young Australian women. METHODS We conducted structured interviews with 974 members of a cohort constructed by tracing all female infants born at a single general hospital in Adelaide between 1973 and 1975. The main outcome measures were pregnancy history, difficulty becoming pregnant and assistance sought to become pregnant. RESULTS Of 657 women aged 30–32 who had sought pregnancy, 24% reported difficulty becoming pregnant and 26% had lost at least one pregnancy. Ovulatory problems (16%) and male fertility problems (13%) were common among those with difficulty. Over half of the women who had difficulty conceiving (58%) sought assistance, largely from specialists (53%). Consultations, tests and education only were common (22%), as were IVF/ICSI (17%). Close to a third (28%) of those seeking assistance were treated only with clomiphene, as were two-thirds (67%) of women with ovulatory problems. CONCLUSIONS In this study, almost a quarter of women in their early 30s reported difficulty conceiving, and over a quarter reported pregnancy loss. This suggests that a significant proportion of young women experience substantial difficulties becoming pregnant. Our findings highlight the need to continue to document the range of women's reproductive experiences and to monitor fertility and treatment-seeking trends. [ABSTRACT FROM AUTHOR]

Small size at birth is associated with exaggerated blood pressure responses to psychological stressors, which increase the risk of developing sustained hypertension in adult life. Explanatory mechanisms for this association are not well characterized. We investigated the hypothesis that an adverse fetal environment, reflected by small size at birth, persistently alters autonomic nervous system and baroreflex control of cardiovascular function, resulting in exaggerated blood pressure and heart rate responses to stressors. Men and women from an Australian prospective cohort study underwent a series of 3 psychological stressors (Stroop, mirror-tracing, and speech) while their blood pressure was recorded continuously using a Portapres. Indices of autonomic function were derived using spectrum analysis (wavelet packet transform), and baroreflex function was estimated using an adaptive autoregressive model. We found that women who were small at birth demonstrated increased levels of low-frequency blood pressure variability at rest (r=-0.28; P<0.05) and during stress (r=-0.42; P<0.001), reduced levels of high-frequency heart period variability (r=0.22; P<0.05), and reduced baroreflex sensitivity (r=0.34; P<0.01). These findings were not present in the men. This study provides evidence that markers of impaired fetal growth are related to autonomic cardiovascular control involving modulation of both sympathetic and parasympathetic function but in a sex-specific manner. We also provide the first human evidence of a relationship between size at birth and baroreflex function. [ABSTRACT FROM AUTHOR]

Purpose: One of the specific aims of life course epidemiology is to assess the explanatory utility of three general hypotheses, namely the critical period hypothesis, the accumulation of risk hypothesis, and the effect modification hypothesis. Methods: A structured regression approach to this problem is illustrated with data from an ongoing longitudinal study of children and their families established in Adelaide in 1998−2000. A series of nested models that correspond to the alternative life course hypotheses were fit in an investigation of the effects of maternal depressive states in early childhood on internalizing child behavior at 9.5 years. Both linear and logistic regression models were considered. Results: The structured regression framework showed the accumulation hypothesis was most plausible for these data. The analyses also provided some evidence of a critical period for the effect of maternal depressive status around child age 2 years on internalizing behavior at 9.5 years. Conclusions: The findings of this study suggest that comparing a suite of nested models to a full model can be useful in attempting to disentangle life course processes. [ABSTRACT FROM AUTHOR]