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The table of contents for this issue of "Gynecologic and Obstetric Investigation" is presented.

Background The Olive baboon is a popular animal model for reproductive and surgical research. The Institute of Primate Research, Nairobi, Kenya, has been using the animal for reproductive research for many years. In the baboon, compared with other smaller non-human primates, it is possible to insert uterine probes such as, catheters, curettes and other linear instruments (to cannulate cervix for uterine procedures like flushing, endometrium biopsy, embryo transfer, etc.). Methods However we noticed in a few animals this was difficult and problematic, particularly in some stages of the menstrual cycle, in retroverted uteri, in extensive adhesions or in some anatomically unique animals and we have developed a technique called ‘Chai technique’ for this purpose. Results and Conclusions The Chai technique is unique to the baboon and not possible in human. It does not seem to cause injuries as frequently as uterine perforation and, in our experience, has been surprisingly successful. [ABSTRACT FROM AUTHOR]

The article reviews the costs of endometriosis, a condition predominantly found in women of reproductive age. The study includes cost-of-illness analyses quantifying the economic impact of endometriosis and cost analyses calculating diagnostic and treatment. Annual healthcare cost associated with endometriosis has been estimated at 2,801 U.S. dollars and productivity cost at 1,023 U.S. dollars per patient. Some of the factors affecting costs are cited.

Discusses a research about endometriosis using a baboon model. Reasons for using primate models in endometriosis research; Treatments for endometriosis; Comparative advantages of baboons with other monkeys including rhesus and cynomolgus as animal models.

Mouse and human embryos, cultured in vitro, undergo a delay in development compared with those grown in vivo. This delay can be caused by suboptimal culture conditions, but possible influences of ovarian stimulation cannot be excluded. The objective of this study was to test the hypothesis that both in vitro and in vivo, preimplantation embryonic development and postimplantation fetal development are impaired in superovulated female mice when compared with naturally cycling controls. A delay in in-vitro blastocyst hatching and in-vivo blastocyst formation (P < 0.03 and P < 0.0001 respectively) and a 40% fetal growth retardation (P < 0.0001) were observed after superovulation in comparison with naturally cycling controls. After transfer to non-stimulated foster mothers, blastocysts from stimulated females had a lower implantation rate (P < 0.005), and developed into fewer living fetuses (P < 0.02), more resorption sites (P < 0.02) and had more pronounced growth retardation (P < 0.0001) when compared with blastocysts from naturally cycling controls. In conclusion, superovulation in the mouse causes a delayed embryonic development in vitro and in vivo, an increased abnormal blastocyst formation, a pronounced fetal growth retardation, and an increased number of resorption sites. If this observation in mice can be extrapolated to humans, it may offer an explanation for the delay in embryonic development and the low birth weight observed after IVF. [ABSTRACT FROM AUTHOR]

This study was performed to determine and compare persistent organic pollutant (POP) levels in different matrices in a female population. A total of 96 serum and 46 adipose tissue samples were collected from infertile women (n = 101) attending Centers for Reproductive Medicine in Belgium from 1996 to 1998. Gas chromatography with electron-capture detection was used to quantify residue levels on a lipid basis of seven organochlorine pesticides (OCPs) and seven polychlorinated biphenyls (PCBs). There was a strong association between adipose tissue and serum residues. The adipose tissue levels of CB-138, 153, 180 and p,p′-DDE were explained by the serum residues. Besides, the accumulation pattern for CB-153 and CB-180 in serum and adipose tissue are mirror images of each other. [ABSTRACT FROM AUTHOR]

Background: This study was performed to test the hypothesis that endometriosis undergoes regression during pregnancy.Methods: This study was performed on 11 baboons with histologically proven endometriosis, housed at the Institute of Primate Research, Nairobi, Kenya. In each individual baboon paired laparoscopies were performed prior to and during pregnancy (6 during first and 5 during second trimester of gestation) with an interval of 5 +/- 3 months. During each laparoscopy the number, size and type of endometriosis implants were noted in detail on a pelvic map; the endometriosis score and stage were calculated according to the revised American Fertility Society (AFS) classification. In each baboon the observations prior to and during pregnancy were compared and analysed by Wilcoxon signed rank test (two-tailed).Results: No significant change was observed in the AFS score or stage of endometriosis, or in the number, size and type of endometriotic lesions in baboons during gestation when compared to the nonpregnant state.Conclusion: In baboons pregnancy had no significant effect on endometriosis during the first or second trimester of gestation. [ABSTRACT FROM AUTHOR]

This study was done to test the hypothesis that the incidence and recurrence of retrograde menstruation is higher in baboons with spontaneous endometriosis than in those without. A total of 399 laparoscopies was performed on 113 female baboons. Group 1 consisted of 84 animals with a normal pelvis (including 23 that later underwent induction of endometriosis and were assigned to group 4), group 2 comprised nine baboons with spontaneous endometriosis acquired during the last 2 years of the study, group 3 had 18 baboons with long-term spontaneous disease, and group 4 comprised 25 animals with induced endometriosis. Retrograde menstruation was defined by the presence of blood-stained peritoneal fluid (red or dark brown) during menses. Recurrence of retrograde menstruation was analysed during the first two laparoscopies in 13 baboons. Peritoneal fluid was 10 times more frequently blood-stained during menses (62%) than during non-menstrual phases (6%). Retrograde menstruation was observed more frequently in animals with spontaneous disease (groups 2 and 3, 83%) than in animals with a normal pelvis (group 1, 51%). Recurrence of retrograde menstruation was observed more frequently in baboons with spontaneous endometriosis (5/5) than in those without (3/8). The results of this study demonstrate that retrograde menstruation is common in baboons, with a higher prevalence and recurrence in animals with spontaneous endometriosis than in those without. [ABSTRACT FROM AUTHOR]

In women with endometriosis, changes in peripheral blood and peritoneal fluid white blood cell (WBC) populations have been reported, but it is known whether these alterations are casually related to or a consequence of endometriosis. The purpose of this study was to test the hypothesis that peripheral blood and peritoneal fluid WBC populations are altered in baboons with spontaneous and induced endometriosis compared to animals without disease. Peripheral blood and peritoneal fluid samples were obtained at laparoscopy from 60 baboons with a normal pelvis (n = 23), spontaneous endometriosis (n = 19) and induced disease (n = 12), luteal phase (n = 20), pregnancy or nursing (n = 11) and in non-cycling animals (n = 8). The WBC concentration was analysed with a Coulter counter and fluorescent antibody cell separation (FACS) analysis was used to measure cluster designation (CD)2, CD4, CD8, interleukin (IL)2R and leucine (Leu) M5 subsets. In peripheral blood, the percentage of CD4+ and IL2R+ cells was increased in baboons with stage II-IV spontaneous or induced endometriosis, suggesting that alterations in peripheral blood WBC populations may be an effect of endometriosis. In peritoneal fluid the WBC concentration and percentages of Leu M5+ macrophages and CD8+ lymphocytes were only increased in baboons with spontaneous endometriosis and not in animals with induced disease, suggesting that alterations in peritoneal fluid WBC populations may lead to the development of endometriosis. In summary, the results of this study suggest that peripheral blood and peritoneal fluid immune cell populations are affected in baboons with endometriosis. [ABSTRACT FROM AUTHOR]

This study was performed to test the hypothesis that anti-endometrial, lymphocyte-mediated cytotoxicity and natural killer (NK) activity are reduced in baboons with endometriosis when compared to animals with a normal pelvis. Lymphocyte-mediated cytotoxicity was determined in 28 baboons (15 with endometriosis, 13 with normal pelvis) and NK cell activity was evaluated in 42 baboons (31 with endometriosis, 11 with normal pelvis). Anti-endometrial lymphocyte-mediated cytotoxicity was determined by a 20 h assay with effector-target ratios of 50:1 and 25:1. The NK activity (K562 cell line as target) was simultaneously measured in all animals during a 4 h assay with effector:target ratios of 200:1, 100:1, 50:1, 25:1, 12:1, 6:1 and 3:1. Statistical analysis was performed using analysis of variance, paired rank, Mann-Whitney, Kruskal-Wallis and Fisher exact tests where appropriate. Lymphocyte-mediated cytotoxicity was significantly lower (P < 0.025) in baboons with endometriosis (mean 5.9 +/- 8.7%, median 0%, range 0-26%) than in animals with a normal pelvis (mean 22.9 +/- 23.0%, median 7%, range 0-78%). This difference could be explained by the absence of cytotoxicity in baboons with moderate to severe endometriosis, probably due to high spontaneous release of 51Cr from labelled target cells. When stricter criteria were used and only animals with a labelling index (maximal/spontaneous release) of > or = 1.7 were analysed (n = 11), the anti-endometrial cytotoxicity was comparable between baboons with and without endometriosis. NK cell activity was also comparable in primates with and without endometriosis. In conclusion, no difference in lymphocyte-mediated cytotoxicity and NK cell activity was observed between baboons with and without endometriosis. [ABSTRACT FROM AUTHOR]

The article discusses the reasons why the gynecology and obstetrics field need to use a noninvasive diagnostic test for minimal to mild endometriosis with a high sensitivity. The presence of endometrial-like tissue outside the uterus is known as endometriosis, and it is associated with a chronic inflammatory reaction in the pelvis and often results in subfertility and pain. The stages of endometriosis include minimal, mild, moderate and severe.

Endometriosis is a gynaecological disorder, characterized by the growth of endometrial tissue outside the uterine cavity. It is the most common cause of pelvic pain and occurs in 20-25% of women with infertility. Although Sampson first described endometriosis in 1927, studies on the prevalence of endometriosis among African women are still lacking. The current thinking is that endometriosis rarely affects women from African origin. However, in African-American women in the USA, endometriosis is one of the commonest indications for major gynaecological surgery and hysterectomy, and is associated with long hospital stay and high hospital charges. There is also some evidence that endometriosis is more commonly found in African- American patients from private practice than in African-American patients treated in public hospitals. The prevalence of endometriosis in African-indigenous women with infertility seems low, possibly due to a different life style (early pregnancy, increased risk for PID and blocked Fallopian tubes) and due to lack of laparascopic facilities and specific training of African gynecologists to diagnose this disease. Specific manifestations like cervical endometriosis and ascites caused by endometriosis appear to be more frequently observed in African-indigenous or African-American women than in women with other ethnic backgrounds. [ABSTRACT FROM AUTHOR]

Considers quantitative assessment of endometrial-peritoneal interaction as a non-invasive diagnostic test for women with endometriosis. Factors that result to endometriosis according to implantation theory; Result of studies on endometrial-peritoneal implantation using baboons as an in vivo culture model; Investigation on the effect of the phase of the menstrual cycle and the presence or absence of endometriosis on the adhesion between endometrium and peritoneum.

Study Question: Which success rates do female and male IVF patients expect, what determines their expectations and do patients reconsider their expectations after receiving a personal IVF prognosis at the expense of anxious reactions?Summary Answer: Female and male IVF patients have unrealistic high expectations which are positively associated with their dispositional optimism, and which are only reconsidered by patients receiving a less than average IVF prognosis, which leads to more anxious reactions in females.What Is Known Already: Female patients undergoing IVF are known to have unrealistic expectations of the success of their own IVF cycle. The available evidence suggests women expect above average performance of their fertility clinic and (family) reproductive systems. The association of gender and personality trait dispositional optimism, with expectations of IVF success and the impact of providing couples with their IVF prognosis have not been studied previously.Study Design, Size, Duration: A total of 148 partnered individuals participated in this prospective survey at two separate points in treatment: following oocyte aspiration (T1) and embryo transfer (T2) (2019-2020, participation rate = 85%). At the time of embryo transfer, gynaecologists provided couples with their IVF prognosis, calculated with the Adapted van Loendersloot model. Women and their male partners completed questionnaires independently and immediately following oocyte aspiration and embryo transfer.Participants/materials, Setting, Methods: Dispositional optimism ('LOT-R' questionnaire) and expectations of IVF success (numerical rating scale) were assessed in eligible couples commencing a 2nd-6th IVF cycle on T1. Expectations of IVF success and anxiety ('Spielberger State-Anxiety Inventory') were (re)assessed on T2. The inter-partner correlation of expectations of IVF success was examined. Linear mixed models examined hypothesized determinants of expectations of IVF success (T1) and explored (determinants of) whether participants reconsidered their expectations after receiving their IVF prognosis (T1-T2) and whether couple's IVF prognosis was associated with anxious reactions (T2).Main Results and the Role Of Chance: The mean of the IVF success rates expected by patients immediately after oocyte aspiration was 59.1% (±20.0), irrespective of gender (P = 0.077). Partners expectations of IVF success were moderately correlated (r = 0.483; P < 0.001). Expectations of IVF success were positively associated with the participant's dispositional optimism (P < 0.001) but were not associated with their partner's dispositional optimism, women's age and their previous (un)successful IVF experiences. Gynaecologists gave couples their calculated IVF prognosis ranging from 4.8% to 69.2% (mean = 30.9%) at the time of embryo transfer. Gender did not influence whether participants reconsidered their expectations after receiving their prognosis. In contrast to the subgroup (n = 78), who received at least an average IVF prognosis and that did not reconsider their expectations of IVF success, the subgroup (n = 70) receiving a below average IVF prognosis lowered their expectations of IVF success (interaction effect: P < 0.001) from 55% to 46%. A below average IVF prognosis was associated with anxious reactions in women but not in men (interaction effect: P = 0.011).Limitations, Reasons For Caution: The study design and sample size were more optimal for examining hypothesized determinants of patient's expectations of IVF success than for studying the impact of sharing prognoses with patients. Whether (reconsidering) expectations influences IVF discontinuation rates and achieved live birth rates has yet to be followed-up.Wider Implications Of the Findings: Clinics are advised to offer patients the opportunity of receiving their IVF prognosis. Providing prognoses is in line with patient preferences and tempers the unrealistic high expectations of both partners in couples with a less than average prognosis. A sensitive communication style is indicated, as lower prognoses are associated with mild anxious reactions in women.Study Funding/competing Interest(s): E.A.F.D. holds a postdoctoral fellowship of the Research Foundation-Flanders (12H9819N) and this study was funded by the Research Council of the KU Leuven (C14/18/106; project of J.V., K.P. and E.A.F.D.) and as an investigator sponsored study of K.P. and E.A.F.D. by Merck nv/sa Belgium, an affiliate of Merck KGaA, Darmstadt, Germany. The authors declare no conflict of interest related to this study.Trial Registration Number: N/A. [ABSTRACT FROM AUTHOR]

Study Question: Can we develop a web-based sex education programme (programme running in a web browser) that addresses the needs of subfertile couples who are advised expectant management for at least 6 months?Summary Answer: The 'Pleasure & Pregnancy' programme addresses couples' needs, is likely to improve couples' sexual functioning, and is subsequently hypothesised to improve the chance of natural pregnancy.What Is Known Already: According to professional guidelines (e.g. the Netherlands and UK) couples with unexplained subfertility and a good chance of natural pregnancy, should be advised at least 6 months of expectant management. Adherence to expectant management is challenging as couples and gynaecologist prefer a more active approach. Targeting sexuality may be useful as subfertility is a risk factor for decreased sexual functioning.Study Design, Size, Duration: A novel programme was developed according to the three steps of the Medical Research Councils' (MRC) framework. First, relevant literature was explored. Second, an interdisciplinary expert panel developed a theory (based on a systematic literature review and patient interviews) on how the chance of natural conception can be improved. Third, the expected process and outcomes were modelled.Participants/materials, Setting, Methods: Two licenced clinical sexologists, two gynaecologists, a clinical embryologist and two midwife-researchers, all from Belgium and the Netherlands, proposed components for the sex education programme. PubMed was searched systematically for randomised controlled trials (RCTs) evaluating the proposed components in different patient populations. The needs of 12 heterosexual Dutch or Belgian couples who were advised expectant management were explored with in-depth interviews. The content and delivery characteristics of the novel programme were described in detail with the aid of 'Intervention Taxonomy'. To model the outcomes, a protocol for an RCT was designed, registered and submitted for publication.Main Results and the Role Of Chance: To help maintain or improve sexual functioning, mainly pleasure, and hence increase pregnancy rates, the web-based Pleasure & Pregnancy programme contains a combination of psychosexual education and couple communication, mindfulness and sensate focus exercises. Information on the biology of conception and interaction with fertility clinic staff and peers were added based on couples' needs to increase potential acceptability.Limitations and Reason For Caution: This paper outlines the development phase of a sex education programme according to the MRC-framework. Whether the Pleasure & Pregnancy programme actually is acceptable, improves sexual functioning, increases pregnancy rates and is cost-effective remains to be determined.Wider Implications Of the Findings: No previous interactive web-based sex education programme has aimed to increase the natural pregnancy rate of subfertile couples by targeting their sexual pleasure. The Pleasure & Pregnancy programme addresses couples' needs and its effect on sexual functioning and pregnancy rate is plausible but remains to be demonstrated by an RCT which is currently ongoing.Study Funding/competing Interest(s): Funding was provided by The Netherlands Organisation for Health Research and Development (ZonMw), Flanders Research Foundation and the University of Amsterdam. C.B.L. is editor-in-chief of Human Reproductionbut was blinded to all parts of the peer review process. The remaining authors have no conflict of interest to report.Trial Registration Number: Not applicable. [ABSTRACT FROM AUTHOR]

An abstract of the article "Longitudinal growth of crown-rump length, gestation sac and yolk sac in pregnancies following fertility treatment," by A. Pexsters and colleagues is presented.

Discusses the use and application of the baboon as a model for research in women's reproductive health. Contribution of primate research to reproductive health in women; Importance of basic and preclinical research in nonhuman primates before application of new assisted reproductive technology in humans; Reasons for not fully utilizing primate models in biomedical research in reproductive health.

This case report describes a couple suffering from infertility secondary to psychogenic anejaculation, which was refractory to all conservative treatment modalities. A first trial of microsurgical vas aspiration in combination with in-vitro fertilization (IVF) resulted in a pregnancy. After 2 years, three more trials of microsurgical vas aspiration in combination with either IVF or subzonal insemination (SUZI) resulted in embryo transfer without pregnancy. Finally, after 3 years, spermatozoa obtained by rectal probe stimulation under general anaesthesia were cryopreserved. A second intracytoplasmic sperm injection (ICSI) procedure using these cryopreserved spermatozoa also resulted in a second pregnancy. Although sperm concentration was in the normal range, in all samples obtained by either rectal probe electrostimulation or microsurgical vas aspiration, motility was <30% in all but two samples. [ABSTRACT FROM PUBLISHER]

An abstract of the article "A comparison of two different balloon catheters for hysterosalpingo-foam sonography (HyFoSy)" by D. Van Schoubroeck and colleagues is presented.

: BACKGROUND Neurofibromatosis type 1 (NF1) and Von Hippel-Lindau (VHL) are dominantly inherited late onset cancer predisposition syndromes caused by mutations in the respective tumor suppressor genes (TSGs) NF1 and VHL. Less frequently TSGs are partially or fully deleted. Preimplantation genetic diagnosis (PGD) for cancer predisposition can be applied to select against the mutant allele in carrier couples. However, microdeletions within a single cell can, at present, not be detected by molecular diagnostic methods usually applied for PGD of monogenic disorders. : METHODS We performed PGD using interphase fluorescent in situ hybridization (FISH) on single blastomeres for three couples of which the women carried a microdeletion. One patient had the recurrent 1.4 Mb microdeletion covering NF1, a second suffered from an intragenic NF1 deletion and the last had a deletion of VHL. : RESULTS In total, seven PGD cycles were carried out for these couples, which resulted in the delivery of a healthy twin for the VHL microdeletion carrier. : CONCLUSIONS FISH-based PGD is a straightforward approach to detect (micro)deletions in single blastomeres. It seems likely that the number of conditions for which PGD-FISH is beneficial will increase rapidly with the advent of high-resolution arrays. [ABSTRACT FROM AUTHOR]

BACKGROUND Several GnRH antagonist protocols are currently used during COS in the context of ART treatments; however, questions remain regarding whether these protocols are comparable in terms of efficacy and safety. OBJECTIVE AND RATIONALE A systematic review followed by a pairwise and network meta-analyses were performed. The systematic review and pairwise meta-analysis of direct comparative data according to the PRISMA guidelines evaluated the effectiveness of different GnRH antagonist protocols (fixed Day 5/6 versus flexible, ganirelix versus cetrorelix, with or without hormonal pretreatment) on the probability of live birth and ongoing pregnancy after COS during ART treatment. A frequentist network meta-analysis combining direct and indirect comparisons (using the long GnRH agonist protocol as the comparator) was also performed to enhance the precision of the estimates. SEARCH METHODS The systematic literature search was performed using Embase (Ovid), MEDLINE (Ovid), Cochrane Central Register of Trials (CENTRAL), SCOPUS and Web of Science (WOS), from inception until 23 November 2021. The search terms comprised three different MeSH terms that should be present in the identified studies: GnRH antagonist; assisted reproduction treatment; randomized controlled trial (RCT). Only studies published in English were included. OUTCOMES The search strategy resulted in 6738 individual publications, of which 102 were included in the systematic review (corresponding to 75 unique studies) and 73 were included in the meta-analysis. Most studies were of low quality. One study compared a flexible protocol with a fixed Day 5 protocol and the remaining RCTs with a fixed Day 6 protocol. There was a lack of data regarding live birth when comparing the flexible and fixed GnRH antagonist protocols or cetrorelix and ganirelix. No significant difference in live birth rate was observed between the different pretreatment regimens versus no pretreatment or between the different pretreatment protocols. A flexible GnRH antagonist protocol resulted in a significantly lower OPR compared with a fixed Day 5/6 protocol (relative risk (RR) 0.76, 95% CI 0.62 to 0.94, I 2 = 0%; 6 RCTs; n = 907 participants; low certainty evidence). There were insufficient data for a comparison of cetrorelix and ganirelix for OPR. OCP pretreatment was associated with a lower OPR compared with no pretreatment intervention (RR 0.79, 95% CI 0.69 to 0.92; I 2 = 0%; 5 RCTs, n = 1318 participants; low certainty evidence). Furthermore, in the network meta-analysis, a fixed protocol with OCP resulted in a significantly lower OPR than a fixed protocol with no pretreatment (RR 0.84, 95% CI 0.71 to 0.99; moderate quality evidence). The surface under the cumulative ranking (SUCRA) scores suggested that the fixed protocol with no pretreatment is the antagonist protocol most likely (84%) to result in the highest OPR. There was insufficient evidence of a difference between fixed/flexible or OCP pretreatment/no pretreatment interventions regarding other outcomes, such as ovarian hyperstimulation syndrome and miscarriage rates. WIDER IMPLICATIONS Available evidence, mostly of low quality and certainty, suggests that different antagonist protocols should not be considered as equivalent for clinical decision-making. More trials are required to assess the comparative effectiveness of ganirelix versus cetrorelix, the effect of different pretreatment interventions (e.g. progestins or oestradiol) or the effect of different criteria for initiation of the antagonist in the flexible protocol. Furthermore, more studies are required examining the optimal GnRH antagonist protocol in women with high or low response to ovarian stimulation. [ABSTRACT FROM AUTHOR]

Background: Intrauterine insemination with ovarian stimulation (IUI-OS) is a first-line treatment for unexplained infertility. Gonadotrophins, letrozole and clomiphene citrate (CC) are commonly used agents during IUI-OS and have been compared in multiple aggregate data meta-analyses, with substantial heterogeneity and no analysis on time-to-event outcomes. Individual participant data meta-analysis (IPD-MA) is considered the gold standard for evidence synthesis as it can offset inadequate reporting of individual studies by obtaining the IPD, and allows analyses on treatment-covariate interactions to identify couples who benefit most from a particular treatment.Objective and Rationale: We performed this IPD-MA to compare the effectiveness and safety of ovarian stimulation with gonadotrophins, letrozole and CC and to explore treatment-covariate interactions for important baseline characteristics in couples undergoing IUI.Search Methods: We searched electronic databases including MEDLINE, EMBASE, CENTRAL, CINAHL, and PsycINFO from their inception to 28 June 2021. We included randomized controlled trials (RCTs) comparing IUI-OS with gonadotrophins, letrozole and CC among couples with unexplained infertility. We contacted the authors of eligible RCTs to share the IPD and established the IUI IPD-MA Collaboration. The primary effectiveness outcome was live birth and the primary safety outcome was multiple pregnancy. Secondary outcomes were other reproductive outcomes, including time to conception leading to live birth. We performed a one-stage random effects IPD-MA.Outcomes: Seven of 22 (31.8%) eligible RCTs provided IPD of 2495 couples (62.4% of the 3997 couples participating in 22 RCTs), of which 2411 had unexplained infertility and were included in this IPD-MA. Six RCTs (n = 1511) compared gonadotrophins with CC, and one (n = 900) compared gonadotrophins, letrozole and CC. Moderate-certainty evidence showed that gonadotrophins increased the live birth rate compared to CC (6 RCTs, 2058 women, RR 1.30, 95% CI 1.12-1.51, I2 = 26%). Low-certainty evidence showed that gonadotrophins may also increase the multiple pregnancy rate compared to CC (6 RCTs, 2058 women, RR 2.17, 95% CI 1.33-3.54, I2 = 69%). Heterogeneity on multiple pregnancy could be explained by differences in gonadotrophin starting dose and choice of cancellation criteria. Post-hoc sensitivity analysis on RCTs with a low starting dose of gonadotrophins (≤75 IU) confirmed increased live birth rates compared to CC (5 RCTs, 1457 women, RR 1.26, 95% CI 1.05-1.51), but analysis on only RCTs with stricter cancellation criteria showed inconclusive evidence on live birth (4 RCTs, 1238 women, RR 1.15, 95% CI 0.94-1.41). For multiple pregnancy, both sensitivity analyses showed inconclusive findings between gonadotrophins and CC (RR 0.94, 95% CI 0.45-1.96; RR 0.81, 95% CI 0.32-2.03, respectively). Moderate certainty evidence showed that gonadotrophins reduced the time to conception leading to a live birth when compared to CC (6 RCTs, 2058 women, HR 1.37, 95% CI 1.15-1.63, I2 = 22%). No strong evidence on the treatment-covariate (female age, BMI or primary versus secondary infertility) interactions was found.Wider Implications: In couples with unexplained infertility undergoing IUI-OS, gonadotrophins increased the chance of a live birth and reduced the time to conception compared to CC, at the cost of a higher multiple pregnancy rate, when not differentiating strategies on cancellation criteria or the starting dose. The treatment effects did not seem to differ in women of different age, BMI or primary versus secondary infertility. In a modern practice where a lower starting dose and stricter cancellation criteria are in place, effectiveness and safety of different agents seem both acceptable, and therefore intervention availability, cost and patients' preferences should factor in the clinical decision-making. As the evidence for comparisons to letrozole is based on one RCT providing IPD, further RCTs comparing letrozole and other interventions for unexplained infertility are needed. [ABSTRACT FROM AUTHOR]

Objectives: To assess intra- and interobserver agreement of routinely performed measurements-crown-rump length (CRL) and mean gestational sac diameter (MSD)-for assessing the likelihood of miscarriage in the first trimester of pregnancy using transvaginal sonography. Methods: A cross-sectional study of CRL and gestational sac measurements in first-trimester pregnancies was conducted in a fetal medicine referral center with a predominantly Caucasian population. Gestational age ranged from 6 to 9 weeks. All patients underwent a transvaginal ultrasound examination using a high-resolution ultrasound machine. Two measurements of CRL and measurements of three diameters of the gestational sac were obtained by two observers. Agreement within and between observers for CRL and between observers for MSD was analyzed using 95% prediction intervals, Bland-Altman plots with 95% limits of agreement and the intraclass correlation coefficient (ICC). Results: In total 54 patients were included in the study, with measurements obtained by both observers in 44 of these. Intra- and interobserver ICCs were high for CRL measurements, with values of 0.992 and 0.993 for intraobserver agreement and 0.993 for interobserver agreement. For the MSD, the interobserver ICC was 0.952. Limits of agreement were ± 8.91 and ± 11.37% for intraobserver agreement of CRL and ± 14.64% for interobserver agreement of CRL. For MSD, the interobserver limits of agreement were ± 18.78%. For an MSD measurement of 20 mm by the first observer, the prediction interval for the second observer was 16.8-24.5 mm. For a CRL measurement of 6 mm, the prediction interval for the second observer was 5.4-6.7 mm. Conclusion: For dating purposes, there is reasonable reproducibility of CRL measurements using transvaginal ultrasonography at 6-9 weeks' gestation. When diagnosing miscarriage based on measurements of CRL care must be taken for values close to any decision boundary. The higher interobserver variability that we observed for MSD has implications for the diagnosis of miscarriage based on this measurement in the absence of a visible embryo or yolk sac. [ABSTRACT FROM AUTHOR]

Study Question: Does ultra-long downregulation with a GnRH agonist (triptorelin depot) in previously operated patients with endometriosis improve the rate of clinical pregnancy with positive fetal heart beat (CPHB) in the subsequent initiated fresh ART cycle?Summary Answer: Ultra-long downregulation with a GnRH agonist prior to ART did not improve the rate of CPHB in the subsequent fresh ART cycle in previously completely operated patients but the trial was underpowered due to early termination.What Is Known Already: Administration of GnRH agonists for a period of 3-6 months prior to ART in women with endometriosis may increase the odds of clinical pregnancy. However, the quality of the studies on which this statement is based is questionable, so these findings need confirmation.Study Design, Size, Duration: A controlled, randomized, open label trial was performed between 1 June 2013 and 31 December 2016 (start and end of recruitment, respectively). Patients with prior complete laparoscopic treatment of any type or stage of endometriosis and an indication for ART were randomized (by a computer-generated allocation sequence) into two groups: the control group underwent ART stimulation in a classical long agonist protocol using preparation with oral contraceptives, the ultra-long group first underwent at least 3 months downregulation followed by a long agonist protocol for ART stimulation. The sample size was calculated to detect a superiority of the ultra-long downregulation protocol, based on the hypothesis that baseline CPHB rate in the control group of 20% would increase to 40% in the ultra-long group. For a power of 20% at a significance level of 5%, based on two-sided testing, including 5% of patients lost to follow-up, the necessary sample size was 172 patients (86 per group).Participants/materials, Setting, Methods: This trial was conducted at the Leuven University Fertility Center, a tertiary care center for endometriosis and infertility, and a total of 42 patients were randomized (21 in the control group and 21 in the ultra-long group).Main Results and the Role Of Chance: Baseline characteristics were similar in both groups. The primary outcome studied-CPHB after the initiated ART treatment-did not differ and was 25% (5/20) in the control group, and 20% (4/20) in the ultra-long group (P > 0.999; relative risk (RR) 1.25, 95% CI 0.41-3.88). Cumulative (fresh + associated frozen) CPHB rates were also similar in the control versus ultra-long group (8/20, 40% vs 6/20, 30%, P = 0.7411; RR = 1.33, 95% CI 0.57-3.19). When other secondary outcomes were compared with the ultra-long group, patients from the control group had a shorter duration of stimulation (mean 11.8 days (SD ± 2.4) versus 13.2 days (SD ± 1.5), P = 0.0373), a lower total dose of gonadotrophins used (mean 1793 IU/d (SD ± 787) vs 2329 (SD ± 680), P = 0.0154), and a higher serum estradiol concentration (ng/ml) at the end of ovarian stimulation on the day of ovulation triggering or cycle cancellation (mean1971 (SD ± 1495) vs 929 (± 548); P = 0.0326), suggesting a better ovarian response in the control group.Limitations, Reasons For Caution: Due to a strong patient preference, nearly exclusively against ultra-long downregulation (even though patients were thoroughly informed of the potential benefits), the targeted sample size could not be achieved and the trial was stopped prematurely.Wider Implications Of the Findings: Conditional power analysis revealed that the probability of confirming the study hypothesis if the study were completed would be low. We hypothesize that in patients with prior complete surgical treatment of endometriosis, the ultra-long protocol does not enhance ART-CPHB rates. Patient's concerns and preferences regarding possible side-effects, and delay of ART treatment start with the ultra-long protocol should be taken into account when considering this type of treatment in women with endometriosis.Study Funding/competing Interest(s): C.T. was during 2 years funded by a grant from the Clinical research Foundation of UZ Leuven (KOF) and during 2 years by the Research Foundation-Flanders (FWO grant number: 1700816N). C.T. reports grants from Clinical Research Foundation of the University Hospitals of Leuven (KOF), grants from Fund for Scientific Research Flanders (FWO), during the conduct of the study; grants, non-financial support and other from Merck SA, non-financial support and other from Gedeon Richter, non-financial support from Ferring Pharmaceuticals, outside the submitted work. T.D. is vice president and head of Global Medical Affairs Fertility, Research and Development, Merck KGaA, Darmstadt, Germany. He is also a professor in Reproductive Medicine and Biology at the Department of Development and Regeneration, Group Biomedical Sciences, KU Leuven (University of Leuven), Belgium and an adjunct professor at the Department of Obstetrics and Gynecology in the University of Yale, New Haven, USA. Neither his corporate role nor his academic roles represent a conflict of interest with respect to the work done by him for this study. A.C. reports personal fees from Merck S.p.A., outside the submitted work. The other co-authors have no conflict of interest.Trial Registration Number: UZ Leuven trial registry SS55300, EudraCT number 2013-000993-32, clinicaltrials.gov NCT02400801.Trial Registration Date: Registration for EudraCT on 1 March 2013.Date Of First Patient’s Enrolment: 4 September 2013. [ABSTRACT FROM AUTHOR]

Study Question: Can the Poor Responder Outcome Prediction (PROsPeR) score identify live birth outcomes in subpopulations of patients with poor ovarian response (POR) defined according to the ESHRE Bologna criteria (female age, anti-Müllerian hormone (AMH), number of oocytes retrieved during the previous cycle (PNO) after treatment with originator recombinant human follitropin alfa?Summary Answer: The PROsPeR score discriminated the probability of live birth in patients with POR using observational data with fair discrimination (AUC ≅ 70%) and calibration, and the AUC losing less than 5% precision compared with a model developed using the observational data.What Is Known Already: Although scoring systems for the likelihood of live birth after ART have been developed, their accuracy may be insufficient, as they have generally been developed in the general population with infertility and were not validated for patients with POR. The PROsPeR score was developed using data from the follitropin alfa (GONAL-f; Merck KGaA, Darmstadt, Germany) arm of the Efficacy and Safety of Pergoveris in Assisted Reproductive Technology (ESPART) randomized controlled trial (RCT) and classifies women with POR as mild, moderate or severe, based upon three variables: female age, serum AMH level and number of oocytes retrieved during the previous cycle (PNO).Study Design, Size, Duration: The external validation of the PROsPeR score was completed using data derived from eight different centres in France. In addition, the follitropin alfa data from the ESPART RCT, originally used to develop the PROsPeR score, were used as reference cohort. The external validation of the PROsPeR score l was assessed using AUC. A predetermined non-inferiority limit of 0.10 compared with a reference sample and calibration (Hosmer-Lemeshow test) were the two conditions required for evaluation.Participants/materials, Setting, Methods: The observational cohort included data from 8085 ART treatment cycles performed with follitropin alfa in patients with POR defined according to the ESHRE Bologna criteria (17.6% of the initial data set). The ESPART cohort included 477 ART treatment cycles with ovarian stimulation performed with follitropin alfa in patients with POR.Main Results and the Role Of Chance: The external validation of the PROsPeR score to identify subpopulations of women with POR with different live birth outcomes was shown in the observational cohort (AUC = 0.688; 95% CI: 0.662, 0.714) compared with the ESPART cohort (AUC = 0.695; 95% CI: 0.623, 0.767). The AUC difference was -0.0074 (95% CI: -0.083, 0.0689). This provided evidence, with 97.5% one-sided confidence, that there was a maximum estimated loss of 8.4% in discrimination between the observational cohort and the ESPART cohort, which was below the predetermined margin of 10%. The Hosmer-Lemeshow test did not reject the calibration when comparing observed and predicted data (Hosmer-Lemeshow test = 1.266688; P = 0.260).Limitations, Reasons For Caution: The study was based on secondary use of data that had not been collected specifically for the analysis reported here and the number of characteristics used to classify women with POR was limited to the available data. The data were from a limited number of ART centres in a single country, which may present a bias risk; however, baseline patient data were similar to other POR studies.Wider Implications Of the Findings: This evaluation of the PROsPeR score using observational data supports the notion that the likelihood of live birth may be calculated with reasonable precision using three readily available pieces of data (female age, serum AMH and PNO). The PROsPeR score has potential to be used to discriminate expected probability of live birth according to the degree of POR (mild, moderate, severe) after treatment with follitropin alfa, enabling comparison of performance at one centre over time and the comparison between centres.Study Funding/competing Interest(s): This analysis was funded by Merck KGaA, Darmstadt, Germany. P.L. received grants from Merck KGaA, outside of the submitted work. N.M. reports grants, personal fees and non-financial support from Merck KGaA outside the submitted work. T.D.H. is Vice President and Head of Global Medical Affairs Fertility, Research and Development at Merck KGaA, Darmstadt, Germany. P.A. has received personal fees from Merck KGaA, Darmstadt, Germany, outside the submitted work. C.R. has received grants and personal fees from Gedeon Richter and Merck Serono S.A.S., France, an affiliate of Merck KGaA, Darmstadt, Germany, outside the submitted work. P.S. reports congress support from Merck Serono S.A.S., France (an affiliate of Merck KGaA, Darmstadt, Germany), Gedeon Richter, TEVA and MDS outside the submitted work. C.A., J.P., G.P. and R.W. declare no conflict of interest.Trial Registration Number: N/A. [ABSTRACT FROM AUTHOR]

Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) play complementary roles in follicle development and ovulation via a complex interaction in the hypothalamus, anterior pituitary gland, reproductive organs, and oocytes. Impairment of the production or action of gonadotropins causes relative or absolute LH and FSH deficiency that compromises gametogenesis and gonadal steroid production, thereby reducing fertility. In women, LH and FSH deficiency is a spectrum of conditions with different functional or organic causes that are characterized by low or normal gonadotropin levels and low oestradiol levels. While the causes and effects of reduced LH and FSH production are very well known, the notion of reduced action has received less attention by researchers. Recent evidence shows that molecular characteristics, signalling as well as ageing, and some polymorphisms negatively affect gonadotropin action. These findings have important clinical implications, in particular for medically assisted reproduction in which diminished action determined by the afore-mentioned factors, combined with reduced endogenous gonadotropin production caused by GnRH analogue protocols, may lead to resistance to gonadotropins and, thus, to an unexpected hypo-response to ovarian stimulation. Indeed, the importance of LH and FSH action has been highlighted by the International Committee for Monitoring Assisted Reproduction Technologies (ICMART) in their definition of hypogonadotropic hypogonadism as gonadal failure associated with reduced gametogenesis and gonadal steroid production due to reduced gonadotropin production or action. The aim of this review is to provide an overview of determinants of reduced FSH and LH action that are associated with a reduced response to ovarian stimulation. [ABSTRACT FROM AUTHOR]

Study Question: Is the microRNA (miRNA) expression pattern of cumulus oophorus cells (COCs) in women undergoing medically assisted reproduction (MAR) procedures differentially modulated according to patient age and gonadotropin treatment strategy?Summary Answer: Maternal age is an independent factor impacting miRNA expression in COCs while gonadotropin treatment may affect follicular miRNA expression and IVF efficacy.What Is Known Already: Epigenetic mechanisms in female infertility are complex and poorly studied. DNA methylation, histone modifications, miRNAs and nucleosome positioning influence cellular machinery through positive and negative feedback mechanisms either alone or interactively. miRNAs are important regulators during oogenesis, spermatogenesis and early embryogenesis, and are reported to play a role in regulating crosstalk between the oocyte and COCs. Although miRNome analysis has been performed in female human reproductive tissues (endometrium, myometrium, cervix and ovaries), epigenetic modifications in women with infertility have not been explored in detail. In addition, the impact of gonadotropin treatments during MAR on miRNA expression in COCs has not been fully investigated.Study Design, Size, Duration: This study was carried out in 53 COC samples obtained from mature metaphase II (MII) oocytes in 53 women undergoing MAR treatment. A total of 38 samples for assay development were pooled by maternal age and gonadotropin treatment into four predetermined subgroups: ≥36 years and recombinant human FSH (r-hFSH), n = 10; ≥36 years and r-hFSH+ recombinant human-luteinizing hormone (r-hLH), n = 10; ≤35 years and r-hFSH, n = 9; ≤35 years and r-hFSH+r-hLH, n = 9. miRNome profiles were determined and compared between subgroups. Expression of defined miRNAs was validated in the remaining fifteen samples, representative of each subgroup, by quantitative polymerase chain reaction (PCR).Participants/materials, Setting, Methods: COCs were processed for miRNA-enriched total RNA extraction and pooled in homogeneous subgroups to obtain a sufficient amount and quality of starting material to perform the analysis. Each pooled sample underwent miRNA profiling using PCR assay system to examine expression of 752 human miRNAs without pre-amplification. Data were analyzed using the delta-delta Ct method for relative quantitation and prediction of target genes (with at least four algorithms predicting the same miRNA-gene interaction pair (HIT)>4). The miRSystem database provided functional annotation enrichment (raw P-value <0.05) of co-expressed miRNAs.Main Results and the Role Of Chance: We found distinctive miRNA expression profiles in each subgroup correlating with age and MAR stimulation. In addition, a number of selective and co-expressed miRNAs were revealed by comparative analysis. A cluster of 37 miRNAs were commonly but differentially expressed in all four pools. Significant differences were observed in expression regulation of 37 miRNAs between age groups (≤35 or ≥36) in women receiving r-hFSH+r-hLH compared to those receiving r-hFSH alone. Higher concentrations and increased numbers of miRNAs were recorded in younger than in older patients, regardless of treatment. Functional and expression studies performed to retrieve common miRNome profiles revealed an enrichment of biological functions in oocyte growth and maturation, embryo development, steroidogenesis, ovarian hyperstimulation, apoptosis and cell survival, glucagon and lipid metabolism, and cell trafficking. The highest scored pathways of target genes of the 37 common miRNAs were associated with mitogen-activated protein kinase (MAPK) signaling pathways, G alpha signaling, transcription regulation, tight junctions, RNA polymerase I and III, and mitochondrial transcription. We identified a potential age- and MAR stimulation-dependent signature in the miRNA landscape of COCs.Limitations, Reasons For Caution: We cannot rule out the possibility that other unknown individual genetic or clinical factors may have interfered with the reported results. Since miRNA profiling was conducted with a predefined array of target probes, other miRNA molecules, potentially modulated by age and hormonal stimulation, may have been missed in this study.Wider Implications Of the Findings: miRNA expression in COCs is modulated by gonadotropin treatment and correlates strongly with age. A better understanding of the expression patterns and functions of miRNAs may lead to the development of novel therapeutics to treat ovarian dysfunction and improve fertility in older women.Study Funding/competing Interest: This study was funded by Merck KGaA, Darmstadt, Germany. All authors declared no competing interest, except SL and TD who are fully employed by Merck KGaA.Trial Registration Number: N/A. [ABSTRACT FROM AUTHOR]

Study Question: Can the Endometriosis Fertility Index (EFI) be estimated accurately before surgery?Summary Answer: The EFI can be estimated accurately based on mere clinical/ultrasound information, with some improvement after adding data from diagnostic laparoscopy.What Is Known Already: The EFI is a validated clinical instrument predicting the probability of pregnancy after endometriosis surgery without the use of ART. Being an end-of-surgery-score, it implies the decision for operative laparoscopy to be made in advance-hence, its role in the pre-surgical decision-making process remains to be established.Study Design, Size, Duration: Single-cohort prospective observational study in 82 patients undergoing complete endometriosis excision (between June and December 2016). Two methods were used to estimate the final EFI: type A based on non-surgical clinical/ultrasound findings only, and type B based on the combination of non-surgical clinical/ultrasound findings and diagnostic laparoscopy data. To calculate EFI type A, an algorithm was created to translate non-surgical clinical/imaging information into rASRM (revised American Society of Reproductive Medicine)-and EFI points. EFI type A and type B estimates were assessed for their clinical and numerical agreement with the final EFI score. Agreement was defined as clinical if EFI scores were within the same range (0-4, 5-6, 7-10), and numerical if their difference was ≤1.Participants/materials, Setting, Methods: All 82 patients underwent complete laparoscopic CO2-laser excision of any rASRM stage of endometriosis in the Leuven University Fertility Centre (LUFC) of University Hospitals Leuven, a tertiary referral centre for both endometriosis and infertility. An anonymized clinical research file was created. For each patient, three different data sets were created, in order to allow the estimation of the (surgical part) EFI and of the rASRM scores, defined as follows: 'Estimated type A' contained only non-surgical clinical/imaging data, 'Estimated type B' included type A information plus the information of the diagnostic laparoscopy and 'Final EFI' included information of type A, type B and all intra-operative information required to calculate the final EFI. To calculate EFI type A without surgical information, a set of rules was used to translate pre-surgical clinical/imaging information into (rASRM and EFI points). Scoring was done by one person (C.T.), with a time interval of 4 weeks between sessions for each EFI type. Next to the EFI, also rASRM score and stage were calculated.Main Results and the Role Of Chance: Agreement rate between estimated EFI type A and final EFI was high for both the clinical (0.915; 95% CI 0.832-0.965) and numerical definition (0.878; 95% CI 0.787-0.940). Agreement rates between estimated EFI type B and final EFI were even higher (clinical (0.988; 95% CI 0.934-1.000), numerical (0.963; 95% CI 0.897-0.992)).Limitations, Reasons For Caution: Type A estimation is dependent on high-level gynaecological ultrasound expertise, which may not be available in all clinics. A small number of patients had no prior clinical, ultrasound (hard markers) or surgical confirmation of the diagnosis of endometriosis. When applying the estimated EFI type A in clinical practice, a priori assumptions of the presence or absence of endometriosis will need to be made in adjunct to the estimation of the estimated type A EFI when counselling patients on the potential benefit of an (at least diagnostic) laparoscopy. The level of agreement for type A or B should also be taken into account when counselling patients on the type of efforts undertaken to attempt to diagnose or rule out endometriosis.Wider Implications Of the Findings: As this study reports, the EFI can be estimated accurately based on clinical/ultrasound data only without the need for any surgical data. This means that the EFI could be used as an instrument to guide joint physician-patient decision-making between surgery, ART or other fertility management options for the individualized treatment of women with endometriosis-related infertility.Study Funding/competing Interest(s): During this study period, C.T. was supported by FWO (Research Fund Flanders, Grant number 1700816N) and UZ Leuven KOF (University Hospitals Leuven, Klinisch Onderzoeksfonds).The LUFC received unrestricted research grants from Ferring Pharmaceuticals and Merck SA. Gedeon Richter and MSD sponsored travel to and attendance at scientific meetings. C.M. received consultancy fees from Lumenis (paid to KU Leuven, no private revenue). T.D. has been vice-president and head of global medical affairs infertility for the multinational pharmaceutical company Merck (Darmstadt, Germany) since 1 October 2015. He continues his academic appointment on a part-time basis as Professor of Reproductive Medicine at the University of Leuven (KU Leuven). T.D. has been vice-president and head of global medical affairs infertility for the multinational pharmaceutical company Merck (Darmstadt, Germany) since October 2015. He is also a Guest Professor in Reproductive Medicine and Biology at the Department of Development and Regeneration, Group Biomedical Sciences, KU Leuven (University of Leuven), Belgium, and an Adjunct Professor at the Department of Obstetrics and Gynecology in the University of Yale, New Haven, USA. This work was initiated before he joined Merck KGaA in October 2015, and completed during the subsequent years.Trial Registration Number: study registration number at UZ Leuven Clinical Trial Centre: S59221. [ABSTRACT FROM AUTHOR]

Objective: To compare the value of using one-stop magnetic resonance imaging (MRI) vs standard radiological imaging as a supplement to transvaginal ultrasonography (TVS) for the preoperative assessment of patients with endometriosis referred for surgery in a tertiary care academic center.Methods: This prospective observational study compared the diagnostic value of the standard preoperative imaging practice of our center, which involves expert TVS complemented by intravenous urography (IVU) for the evaluation of the ureters and double-contrast barium enema (DCBE) for the evaluation of the rectum, sigmoid and cecum, with that of expert TVS complemented by a 'one-stop' MRI examination evaluating the upper abdomen, pelvis, kidneys and ureters as well as rectum and sigmoid on the same day, for the preoperative triaging of 74 women with clinically suspected deep endometriosis. The findings at laparoscopy were considered the reference standard. Patients were stratified according to their need for monodisciplinary surgical approach, carried out by gynecologists only, or multidisciplinary surgical approach, involving abdominal surgeons and/or urologists, based on the extent to which endometriosis affected the reproductive organs, bowel, ureters, bladder or other abdominal organs.Results: Our standard preoperative imaging approach and the combined findings of TVS and MRI had similar diagnostic performance, resulting in correct stratification for a monodisciplinary or a multidisciplinary surgical approach of 67/74 (90.5%) patients. However, there were differences between the estimation of the severity of disease by DCBE and MRI. The severity of rectal involvement was underestimated in 2.7% of the patients by both TVS and DCBE, whereas it was overestimated in 6.8% of the patients by TVS and/or DCBE.Conclusions: Complementary to expert TVS, 'one-stop' MRI can predict intraoperative findings equally well as standard radiological imaging (IVU and DCBE) in patients referred for endometriosis surgery in a tertiary care academic center. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]