Sperm DNA fragmentation on the day of fertilization is not associated with embryologic or clinical outcomes after IVF/ICSI.

PURPOSE: To evaluate if sperm DNA fragmentation (SDF) in the sample used for intracytoplasmic sperm injection (ICSI) impacts outcomes after euploid blastocyst transfer. METHODS: Prospective cohort study of couples undergoing IVF with preimplantation genetic testing for aneuploidy from December 2014-June 2017. Sperm collected on the day of ICSI was analyzed for SDF using the sperm chromatin structure assay (SCSA®). Semen analysis parameters, embryologic outcomes, and clinical outcomes after euploid blastocyst transfer were compared between groups with DNA fragmentation index (DFI) ≤ 15% and DFI > 15% using Mann-Whitney U, t tests, and generalized linear mixed effects models. RESULTS: Two hundred thirty-four patients were included. One hundred seventy-nine men had DFI ≤ 15% (low DFI group) and 55 men had DFI > 15% group (high DFI group). Total motile sperm and sperm concentration were significantly lower in the group with DFI > 15% vs. DFI ≤ 15%. There was no difference in fertilization (86.3 vs. 84.2%, adjusted OR (95% CI) 0.86 (0.63-1.18)), blastulation (49.5 vs. 48.8%, adjusted OR 1.02 (0.75-1.36)), or euploidy (55.7 vs. 52.1%, adjusted OR 0.96 (0.7-1.31)) between the low and high DFI groups, respectively. Clinical outcomes were similar between low and high DFI groups, including implantation rate (68.8 vs. 79.8%), ongoing pregnancy rate (65.9 vs. 72.6%), and miscarriage rate (4.2 vs. 8.8%), respectively. CONCLUSION: Sperm DNA fragmentation on the day of ICSI is not associated with embryologic or clinical outcomes after euploid blastocyst transfer. Increasing levels of SDF are associated with low sperm concentration and total motile sperm count.

Obstetrical complications of thin endometrium in assisted reproductive technologies: a systematic review.

PURPOSE: The aim of the systematic review is to describe the obstetrical complications associated with pregnancies in the context of a thin endometrial lining. METHODS: Systematic review of the literature. RESULTS: Patients who conceive in the setting of a thin endometrium have a significantly increased risk of early pregnancy loss, namely miscarriage and ectopic pregnancy. These patients also have a twofold increase in low birth weight and preterm delivery, as well as a significantly higher risk of intrauterine growth restriction and composite adverse perinatal outcomes. CONCLUSIONS: In addition to the lower probability of conception, a thin endometrium in assisted reproductive technologies appears to be associated with both early and late pregnancy complications. These pregnancies thus warrant special attention and close follow-up from obstetricians.

Double intrauterine insemination (IUI) of no benefit over single IUI among lesbian and single women seeking to conceive.

PURPOSE: To explore clinical benefit of performing two intrauterine inseminations (IUI) 24 h apart-a double IUI vs. a single IUI among lesbian and single women. METHODS: Retrospective cohort study using electronic medical record review during a 17-year period (11/1999-3/2017). A total of 11,396 patients at a single academic-affiliated private practice were included in this study. All cycles with a single or double IUI were included. A sub-analysis of first cycles only (n = 10,413) was also performed. Canceled IVF cycles converted to IUI were excluded. T tests and Wilcoxon rank-sum tests were used for continuous data, and chi-square for categorical data. Multivariable logistic regression controlled for patient age, day 3 follicle-stimulating hormone (D3 FSH), body mass index (BMI), peak estradiol (E2), and post-wash total motile sperm counts to model the association between IUI number and ongoing pregnancy rate (OPR) according to sperm source (autologous vs. donor). Generalized estimating equations and mixed effect models accounted for multiple cycles from the same woman. Adjusted odds ratio (AOR) with 95% CI was determined. Sub-analyses of sexual orientation and partner status were performed to compare heterosexual couples with proven infertility to women with lesbian and single women. RESULTS: During the study period, 22,452 cycles met inclusion criteria (single IUI 1283 vs. double IUI 21,169). Mean patient age and BMI were similar between groups. For couples using autologous sperm, OPR was significantly higher with double IUI (12.0% vs. 14.1%; p = 0.0380). A similar increase was observed for donor sperm OPR among heterosexual couples (14.4% vs. 16.2%), though this did not reach statistical significance (p = 0.395). A sub-analysis restricted to donor sperm demonstrates a clinical benefit of second IUI in heterosexual couples, 8.5% vs. 17.6% OPR (AOR 2.94; CI 1.00-10.99; p = 0.0496). When lesbian and single patients were evaluated, there was no difference (17.2% vs. 15.2%; AOR 0.99; CI 0.59-1.70; p = 0.0958). CONCLUSIONS: Double IUI is associated with a significantly higher OPR for heterosexual couples using an autologous or donor sperm source. The benefit of a second IUI is less clear in patients with undocumented fertility status using donor sperm, such as single and lesbian women.

The dilemma of aneuploidy screening on low responders.

PURPOSE OF REVIEW: Preimplantation genetic testing for aneuploidy (PGT-A) has been demonstrated to improve implantation and pregnancy rates and decrease miscarriage rates over standard morphology-based embryo selection. However, there are limited data on its efficacy in patients with diminished ovarian reserve or a poor response to stimulation who may have fewer embryos to select amongst. RECENT FINDINGS: Early findings demonstrate that PGT-A reduces the miscarriage rate and decreases the time to delivery in poor responders. These studies highlight the importance of designing trials that compare outcomes over multiple cycles as the benefit of PGT-A in this patient population lies in eliminating the time lost to futile transfers of aneuploid embryos. Furthermore, recent studies have demonstrated that a catch-all category of 'poor responder' may need to be reevaluated as different subpopulations of patients with low response exhibit different clinical characteristics. SUMMARY: More information is needed on characterizing the physiology of ovarian aging across multiple phenotypes of diminished ovarian reserve and establishing the predictive value of aneuploid results across multiple PGT-A platforms. However, initial data suggests benefit of PGT-A in poor responders.

Endometrial microbiome.

PURPOSE OF REVIEW: There have been great improvements in assisted reproduction in the recent decade; however, there are still a significant number of chromosomally normal blastocysts that fail to produce live births. The human microbiome is the totality of the microbes and their genomes that exist in and on the host. The understanding of its impact on health and human disease, particularly in human reproduction, is evolving. RECENT FINDINGS: New technologies have empowered metagenomic sample analysis that allows for more fully characterizing the reproductive tract microbiome. With these technologies, we have determined not only that sites previously thought to be sterile in fact have robust microbiomes, but also have better characterized the normal and abnormal vaginal and endometrial microbiome. SUMMARY: The understanding of the microbiome in health and human disease, in particular in relation to human reproduction, is in its infancy. As the reproductive tract dysbiosis are better characterized and understood, we may be better equipped to manipulate it more expertly.

Vitamin D in human reproduction.

PURPOSE OF REVIEW: Vitamin D deficiency has been associated with a wide range of human disease states and the global epidemic, particularly in reproductive aged women, has led to a focus on this complex hormones role in human reproduction. Indeed vitamin D receptors are found throughout the reproductive tract in the ovary, endometrium, and the placenta. It has roles both in calcium-dependent and independent pathways. However, agreement upon the most appropriate way to assess vitamin D status and ultimately its activity at various sites has proven challenging. RECENT FINDINGS: Investigators have studied vitamin D's role in assisted reproduction and found successful outcomes are correlated with vitamin D replete status. However, subsequent studies have found mixed results when parsing its role in folliculogenesis and oogenesis versus its impact on embryonic implantation in the endometrium. Correlation was shown in a donor oocyte model which suggests endometrial involvement; however, in a euploid blastocyst transfer model with attention to embryo and endometrial synchrony this was not seen. It may be that the major impact is proximal to blastocyst formation at the site of folliculogenesis as has been shown in a primate model. Taken together, these studies suggest that vitamin D's role may be more sophisticated when it comes to reproductive success. Further, it has become clear that the nonstandard method of determining vitamin D status in the clinical and research settings requires clarification to ensure more comparable data in future studies. SUMMARY: Vitamin D has clear roles in human health and disease, and its impact on human reproduction seems promising but requires clarification. With new techniques for assessing its status in patients and its impact at end organs as well as evolving theories regarding its potential to influence folliculogenesis, endometrial receptivity, and ovarian aging, we will soon gain additional clarity and hope to be able to impact reproductive success in a positive way.

Expanded carrier screening in an infertile population: how often is clinical decision making affected?

PURPOSE: Options for preconception genetic screening have grown dramatically. Expanded carrier screening (ECS) now allows for determining carrier status for hundreds of genetic mutations by using a single sample, and some recommend ECS prior to in vitro fertilization. This study seeks to evaluate how often ECS alters clinical management when patients present for infertility care. METHODS: All patients tested with ECS at a single infertility care center from 2011 to 2014 were evaluated. The overall rate of positive ECS results and the number of couples who were carriers of the same genetic disorder were evaluated. RESULTS: A total of 6,643 individuals were tested, representing 3,738 couples; 1,666 (25.1%) of the individuals had a positive test result for at least one disorder. In 8 of the 3,738 couples, both members of the couple were positive for the same genetic disorder or had a test result that placed them at risk of having an affected child. Three of eight cases were cystic fibrosis. In this cohort, ECS affected clinical care eight times after 6,643 tests (0.12%, confidence interval: 0.05-0.24%) in 3,738 couples (0.21%, confidence interval: 0.09-0.42%). CONCLUSIONS: ECS is becoming more widespread. In a large case series, ECS affected clinical decision making for patients presenting for infertility care in 0.21% of cases. This information must be weighed when utilizing these tests and may be a helpful part of patient counseling.Genet Med 18 11, 1097-1101.

Embryonic aneuploidy does not differ among genetic ancestry according to continental origin as determined by ancestry informative markers.

STUDY QUESTION: Is embryonic aneuploidy, as determined by comprehensive chromosome screening (CCS), related to genetic ancestry, as determined by ancestry informative markers (AIMs)? SUMMARY ANSWER: In this study, when determining continental ancestry utilizing AIMs, genetic ancestry does not have an impact on embryonic aneuploidy. WHAT IS KNOWN ALREADY: Aneuploidy is one of the best-characterized barriers to ART success and little information exists regarding ethnicity and whole chromosome aneuploidy in IVF. Classifying continental ancestry utilizing genetic profiles from a selected group of single nucleotide polymorphisms, termed AIMs, can determine ancestral origin with more accuracy than self-reported data. STUDY DESIGN, SIZE, DURATION: This is a retrospective cohort study of patients undergoing their first cycle of IVF with CCS at a single center from 2008 to 2014. There were 2328 patients identified whom had undergone IVF/CCS and AIM genotyping. PARTICIPANTS/MATERIALS, SETTING, METHODS: All patients underwent IVF/ICSI and CCS after trophectoderm biopsy. Patients' serum was genotyped using 32 custom AIMs to identify continental origin. Admixture proportions were determined using Bayesian clustering algorithms. Patients were assigned to the population (European, African, East Asian or Central/South Asian) corresponding to their greatest admixture proportion. MAIN RESULTS AND THE ROLE OF CHANCE: The mean number of embryos tested was 5.3 (range = 1-40) and the mode was 1. Patients' ethnic classifications revealed European (n = 1698), African (n = 103), East Asian (n = 206) or Central/South Asian (n = 321). When controlling for age and BMI, aneuploidy rate did not differ by genetic ancestry (P = 0.28). LIMITATIONS, REASONS FOR CAUTION: The study type (retrospective) and the ability to classify patients by continental rather than sub-continental origin as well as the predominantly European patient mix may impact generalizability. Post hoc power calculation revealed power to detect a 16.8% difference in embryonic aneuploidy between the two smallest sample size groups. WIDER IMPLICATIONS OF THE FINDINGS: These data do not support differences in embryonic aneuploidy among various genetic ancestry groups in patients undergoing IVF/CCS. We used a novel approach of determining continental origin using a validated panel of AIMs as opposed to patient self-reported ethnicities. It does not appear that specific recommendations for aneuploidy screening should be made based upon continental heritage. STUDY FUNDING/COMPETING INTERESTS: None.

FMR1 gene CGG repeat variation within the normal range is not predictive of ovarian response in IVF cycles.

The relationship between FMR1 CGG premutation status and decreased ovarian responsiveness is well established. The association between FMR1 CGG repeat number in the currently defined normal range (less than 45 repeats) and ovarian reserve, however, is controversial. This retrospective study examined whether variation in CGG repeat number in the normal range was associated with markers of ovarian response in IVF cycles. The first IVF cycle of 3006 patients with FMR1 CGG repeat analysis was examined. Only patients carrying two alleles with less than 45 CGG repeats were included for analysis. The CGG repeat number furthest from the modal peak was plotted against number of mature oocytes retrieved and no correlation was identified. Patients were also separated into biallelic genotype groups, based on the recently proposed narrower "new normal" range of 26-34 CGG repeats. A linear regression showed that none of the biallelic genotype groups were associated with a decreased oocyte yield. The euploidy rates after comprehensive chromosomal screening were equivalent among the genotype groups. No difference was found in the rate of cycle cancellation for poor response. Despite increasing use, FMR1 CGG repeats in the normal range cannot be used as a predictor of ovarian response to gonadotrophin stimulation.

Dehydroepiandrosterone (DHEA) supplementation results in supraphysiologic DHEA-S serum levels and progesterone assay interference that may impact clinical management in IVF.

PURPOSE: Dehydroepiandrosterone (DHEA) is often prescribed for poor responders in IVF in an effort to improve response to ovarian stimulation. The effect of DHEA supplementation and resultant supraphysiologic DHEA-S serum levels on sex steroid assays has not been evaluated in this population. This study seeks to determine the relationship between DHEA supplementation and progesterone measurements to characterize the degree of interference with particular immunoassays. METHODS: Characterization was accomplished in two phases. First, DHEA-S standard control reagents with no progesterone present were assayed for both DHEA-S and progesterone levels. Second, serum pools from 60 unique IVF patients' serum were used to create six pooled serum samples: three from patients on DHEA supplementation and three from patients not on DHEA supplementation. The three pools were composed of patients whose serum fell into low, medium, and high progesterone ranges. Baseline DHEA-S and progesterone were measured, and the mean level of DHEA-S in the mid-range progesterone pool was used as the mid-point for addition of DHEA-S standard to the serum pools from patients without DHEA supplementation. Progesterone from these pools was then measured on three commercially available immunoassay systems. RESULTS: The first experiment revealed a linear increase in progesterone when analyzing the DHEA-S standard ranging from 0.5 µg/dL [corrected] in the blank control (no DHEA-S) to up to 2.0 µg/dL [corrected] in the high control (DHEA-S >700 µg/dL), [corrected] indicating that the DHEA-S cross-reacts with the progesterone assays. In the second experiment, patients' serum DHEA-S and progesterone were measured from pooled serum samples of those taking DHEA and those not taking DHEA. Adding DHEA-S to the pooled serum of those not taking DHEA resulted in a linear increase in progesterone levels on two of three commercially available immunoassays (p < 0.05). CONCLUSIONS: DHEA-S can interfere with standard progesterone immunoassays used in clinical ART programs, and thus serum progesterone levels in IVF patients on DHEA supplementation may not reflect truly bioactive progesterone.

Multiple thrombophilic single nucleotide polymorphisms lack a significant effect on outcomes in fresh IVF cycles: an analysis of 1717 patients.

PURPOSE: The aim of the study is to determine if thrombophilic single nucleotide polymorphisms (SNPs) affect outcomes in fresh in vitro fertilization (IVF) cycles in a large general infertility population. METHODS: A prospective cohort analysis was performed at a university-affiliated private IVF center of female patients undergoing fresh non-donor IVF cycles. The effect of the following thrombophilic SNPs on IVF outcomes were explored: factor V (Leiden and H1299R), prothrombin (G20210A), factor XIII (V34L), ß-fibrinogen (-455G → A), plasminogen activator inhibitor-1 (4G/5G), human platelet antigen-1 (a/b9L33P), and methylenetetrahydrofolate reductase (C677T and A1298C). The main outcome measures included positive pregnancy test, clinical pregnancy, embryo implantation, live birth, and pregnancy loss. RESULTS: Patients (1717) were enrolled in the study, and a total of 4169 embryos were transferred. There were no statistically significant differences in positive pregnancy test, clinical pregnancy, embryo implantation, live birth, or pregnancy loss in the analysis of 1717 patients attempting their first cycle of IVF. Receiver operator characteristics and logistic regression analyses showed that outcomes cannot be predicted by the cumulative number of thrombophilic mutations present in the patient. CONCLUSIONS: Individual and cumulative thrombophilic SNPs do not affect IVF outcomes. Therefore, initial screening for these SNPs is not indicated.

Vitamin D levels do not affect IVF outcomes following the transfer of euploid blastocysts.

OBJECTIVE: We sought to characterize the relationship between serum 25-hydroxy vitamin D (25-OH D) levels and implantation and clinical pregnancy rates in women who undergo a euploid blastocyst embryo transfer. STUDY DESIGN: This retrospective cohort study, conducted in an academic setting, included 529 cycles in which comprehensive chromosome screening was performed as part of routine infertility care with an autologous transfer of 1 or 2 euploid blastocysts. After excluding repeat cycles there were 517 unique cycles representing 517 women for evaluation. Vitamin D levels from serum samples obtained on the day of ovulation trigger in the fresh in vitro fertilization cycle were analyzed. The primary outcome was ongoing pregnancy rate as defined by sonographic presence of fetal heart rate at >8 weeks' gestation. RESULTS: For the population as a whole, serum vitamin D ranges and pregnancy outcomes did not correlate. Furthermore, pregnancy rates did not differ when comparing women in different strata of vitamin D levels (<20, 20-29.9, and ≥30 ng/mL). No meaningful breakpoint for vitamin D levels and ongoing pregnancy rate was identified using receiver operating characteristic analysis with the resultant line possessing an area under the curve of 0.502. Multivariate logistic regression controlling for age, transfer order, race, season, and body mass index did not yield a different result. The study was powered to detect an 18% difference in ongoing pregnancy rates between patients grouped by the 3 vitamin D ranges. CONCLUSION: In women undergoing euploid embryo transfer, vitamin D status was unrelated to pregnancy outcomes. Measuring serum 25-OH vitamin D levels does not predict the likelihood that euploid blastocysts will implant. These results may not apply to women who do not undergo extended embryo culture, blastocyst biopsy for comprehensive chromosome screening, and euploid embryo transfer.

Investigating the optimal preconception TSH range for patients undergoing IVF when controlling for embryo quality.

PURPOSE: The ideal thyroid-stimulating hormone (TSH) range for infertile women attempting conception has not been determined. Current recommendations include optimizing the preconception TSH value to ≤2.5 mIU/L, which is the established goal for pregnant women. The aim of this study was to determine if there is a distinct range of TSH ≤2.5 mIU/L for infertile women undergoing in vitro fertilization (IVF) that improves reproductive outcomes. METHODS: One thousand five hundred ninety-nine euploid blastocyst transfer cycles were evaluated in which TSH measurements were obtained 8 days after embryo transfer. Only euploid embryo transfers were included in an effort to control for embryo quality. Patients were separated into TSH groups utilizing 0.5 mIU/L increments. Implantation, live birth, and miscarriage rates among the TSH groups were compared. Outcomes for individuals on thyroid hormone supplementation and those not requiring supplementation were evaluated. RESULTS: There was no difference in implantation (p = 0.56), live birth (p = 0.36), or miscarriage rates (p = 0.10) between TSH groups. Receiver operating characteristic (ROC) curves for implantation, live birth, and miscarriage approached the line of no discrimination, signifying that there is no value of TSH within the recommended range for pregnancy (≤2.5 mIU/L) that predicts IVF outcomes better than other values in this range. Live birth rates for patients requiring thyroid hormone supplementation and those not on medication were similar (p = 0.86). CONCLUSIONS: The recommended TSH range for pregnancy (≤2.5 mIU/L) may be applied to infertile patients attempting conception without a need for further adjustment.

Endometrial disruption does not improve implantation in patients who have failed the transfer of euploid blastocysts.

PURPOSE: To assess the impact of single pass outpatient endometrial biopsy in patients at the highest risk for an endometrial cause for failed implantation; those that have failed to conceive despite the transfer of morphologically normal euploid embryos. METHODS: This is a retrospective cohort study consisting of all patients less than 42 years old who failed their first euploid blastocyst transfer and subsequently completed a second transfer cycle of euploid blastocysts. Cycles were analyzed to determine if a single pass endometrial biopsy, termed 'endometrial disruption', was performed in a cycle preceding their second embryo transfer. Transfer outcomes were analyzed and implantation rates calculated. Data analysis was performed to compare outcomes between patients who had endometrial disruption performed versus those that did not. RESULTS: Two hundred ninety patients failed their first euploid embryo transfer and subsequently completed a second euploid embryo transfer and were included. Thirty-nine patients underwent endometrial disruption and 251 did not. There were no statistical differences in clinical implantation rate or sustained implantation rate between the group with endometrial disruption and subjects without any intervention (Clinical IR, 43.6 % vs. 55.0 %, p = 0.13; 38.5 % vs. 42.6 %, p = 0.60). When controlling for transfer order there was no statistical difference noted in implantation rates. CONCLUSIONS: Single pass endometrial biopsy has no impact on endometrial receptivity in the highest risk subgroup- patient's that have failed to sustain the transfer of morphologically normal euploid embryos- as evidenced by equivalent implantation rates. It is possible that variations in technique may alter outcomes and randomized trials are needed to answer this question.

Obstetrical and neonatal outcomes from the BEST Trial: single embryo transfer with aneuploidy screening improves outcomes after in vitro fertilization without compromising delivery rates.

OBJECTIVE: We sought to determine whether performing elective single embryo transfer (eSET) after trophectoderm biopsy and rapid aneuploidy screening results in improved obstetrical and neonatal outcomes compared with transferring 2 untested embryos. STUDY DESIGN: The Blastocyst Euploid Selective Transfer (BEST) Trial enrolled infertile couples with a female partner up to age 42 years who were undergoing in vitro fertilization. They were randomized to receive transfer of a single euploid embryo (eSET) or to the standard of care with transfer of 2 embryos that were not biopsied for aneuploidy screening (untested 2-embryo transfer). Gestational age at delivery, birthweight, and neonatal intensive care unit (NICU) lengths of stay were compared with Mann-Whitney U. The risk of preterm delivery, low birthweight, and NICU admission were compared with χ(2). RESULTS: Among the 175 randomized patients, the delivery rates were similar (69% after euploid eSET vs 72% after untested 2-embryo transfer; P = .6) through the fresh cycle and up to 1 frozen transfer, with a dramatic difference in multiple births (1.6% vs 47%; P < .0001). The risk of preterm delivery (P = .03), low birthweight (P = .002), and NICU admission (P = .04) were significantly higher after untested 2-embryo transfer. Babies born after untested 2-embryo transfer spent >5 times as many days in the NICU (479 vs 93 days; P = .03). CONCLUSION: By enhancing embryo selection with a validated method of aneuploidy screening, a single euploid embryo with high reproductive potential can be selected for transfer. Using this approach, eSET can be performed without compromising delivery rates and improving the chance of having a healthy, term singleton delivery after in vitro fertilization.

Aneuploidy across individual chromosomes at the embryonic level in trophectoderm biopsies: changes with patient age and chromosome structure.

PURPOSE: To characterize each chromosome's risk for being involved in embryonic aneuploidy. METHODS: This is a retrospective cohort study conducted at a single, academic center. The cohort consisted of 15,169 consecutive trophectoderm biopsies which then underwent comprehensive chromosome screening utilizing validated real-time polymerase chain reaction (RT-PCR) or single nucleotide polymosphism (SNP) array platforms. Analysis was done to determine probability of aneuploidy by chromosome, changes in that risk with increasing maternal age, and in relationship of aneuploidy to chromosomal structure as classified by prior cytogenetic literature. RESULTS: The highest prevalence of imbalances leading to aneuploidy was seen for chromosomes 13, 15, 16, 18, 19, 21, and 22. While elevated in all age groups, there was a disproportionate rise in aneuploidy rates for these chromosomes with increasing maternal age. When classic cytogenetic karyotype groups were compared, the overall smaller groups D, E, and G were associated with the highest rates. Similarly, when grouped based upon structure, acrocentric chromosomes exhibited the highest rates of aneuploidy, followed by the metacentric chromosomes, with the lowest prevalence of error in those with submetacentric structures. CONCLUSIONS: The highest rates of chromosomal aneuploidy were found in chromosomes known to be involved in clinically detectable, abnormal pregnancies, not just simply implantation failure. The rate of aneuploidy in these chromosomes rises disproportionately with age when compared to the other chromosomes which may provide information about chromosomal susceptibility to aging. The biological structure groupings did show varied aneuploidy rates which may provide insight into the biology of aneuploidy.

Probability of Pregnancy With Mono vs Multiple Folliculogenesis in Women With Unexplained Infertility.

Context: Ovarian stimulation (OS) increases pregnancy rates but can cause multiple folliculogenesis and multiple pregnancy. Objective: To determine whether the probability of pregnancy differs in OS cycles with mono- vs multifolliculogenesis in women with unexplained infertility (UI). Design: Secondary analysis of a multicenter, randomized controlled trial: Assessment of Multiple Intrauterine Gestations from Ovarian Stimulation with 3 treatment arms: gonadotropins, clomiphene, or letrozole, combined with intrauterine insemination. Women were categorized as having either 1 or ≥ 2 mature follicles (≥ 16 mm). Relative risk (RR) and 95% CIs for clinical pregnancy and live birth by number of follicles were estimated using generalized linear models adjusted for age, body mass index, years of infertility, and history of prior live birth. Setting: 12 US-based clinical sites. Participants: Normally cycling women aged 18 to 40 years with a normal uterine cavity and at least 1 patent fallopian tube. Male partners with ≥ 5 million total motile sperm. Interventions: Gonadotropins, clomiphene, or letrozole with insemination. Main Outcome Measures: Clinical pregnancy rates (CPR) and live birth rates (LBR). Results: A single mature follicle > 16 mm resulted in lower CPR (RR, 0.70; 95% CI, 0.54-0.90) and LBR (RR, 0.67; 95% CI, 0.51-0.89) compared with ≥ 2 mature follicles. When stratified by treatment modality, no association of follicle number with CPR or LBR was observed for letrozole or clomiphene, but women using gonadotropins had lower CPR and LBR with monofolliculogenesis. Conclusion: In couples undergoing gonadotropin treatment for UI, monofolliculogenesis following OS is related to a lower rate of live birth.