The impact of peak estradiol during controlled ovarian stimulation on the cumulative live birth rate of IVF/ICSI in non-PCOS patients

Molecular Determinants of Uterine Receptivity: Comparison of Successful Implantation, Recurrent Miscarriage, and Recurrent Implantation Failure

Embryo implantation is one of the most remarkable phenomena in human reproduction and is not yet fully understood. Proper endometrial function as well as a dynamic interaction between the endometrium itself and the blastocyst-the so-called embryo-maternal dialog-are necessary for successful implantation. Several physiological and molecular processes are involved in the success of implantation. This review describes estrogen, progesterone and their receptors, as well as the role of the cytokines interleukin (IL)-6, IL-8, leukemia inhibitory factor (LIF), IL-11, IL-1, and the glycoprotein glycodelin in successful implantation, in cases of recurrent implantation failure (RIF) and in cases of recurrent pregnancy loss (RPL). Are there differences at the molecular level underlying RIF or RPL? Since implantation has already taken place in the case of RPL, it is conceivable that different molecular biological baseline situations underlie the respective problems.

Which transfer day results in the highest live birth rate for PCOS patients undergoing in vitro fertilization?

BACKGROUND

Polycystic ovary syndrome (PCOS) has unusual levels of hormones. The hormone receptors in the endometrium have a hostile effect and make the microenvironment unfavorable for embryo implantation. The use of gonadotropin stimulation during in vitro fertilization (IVF) may have an impact on embryo implantation and live birth rate. According to recent data, the clinical results of day 4 embryo transfer (D4 transfer) were on par with those of day 5 embryo transfer (D5 transfer) in IVF-ET. There are few studies comparing the outcomes of transplants with various etiologies and days. The purpose of this study was to determine which transfer day had the best result for PCOS patients undergoing IVF.

METHODS

This retrospective cohort study was conducted in the Xingtai Infertility Specialist Hospital between January 2017 and November 2021. A total of 1,664 fresh ART cycles met inclusion criteria, including 242 PCOS transfers and 1422 tubal factor infertility transfers.

CONCLUSIONS

PCOS individuals had the highest live birth rate on D4 transferred. It was not need to culture embryos to blastocysts to optimize embryo transfer for PCOS women. This could be a novel approach to transplantation for PCOS.

The pathophysiological role of estrogens in the initial stages of pregnancy: molecular mechanisms and clinical implications for pregnancy outcome from the periconceptional period to end of the first trimester

BACKGROUND

Estrogens regulate disparate female physiological processes, thus ensuring reproduction. Altered estrogen levels and signaling have been associated with increased risks of pregnancy failure and complications, including hypertensive disorders and low birthweight babies. However, the role of estrogens in the periconceptional period and early pregnancy is still understudied.

OBJECTIVE AND RATIONALE

This review aims to summarize the current evidence on the role of maternal estrogens during the periconceptional period and the first trimester of pregnancies conceived naturally and following ART. Detailed molecular mechanisms and related clinical impacts are extensively described.

SEARCH METHODS

Data for this narrative review were independently identified by seven researchers on Pubmed and Embase databases. The following keywords were selected: 'estrogens' OR 'estrogen level(s)' OR 'serum estradiol' OR 'estradiol/estrogen concentration', AND 'early pregnancy' OR 'first trimester of pregnancy' OR 'preconceptional period' OR 'ART' OR 'In Vitro Fertilization (IVF)' OR 'Embryo Transfer' OR 'Frozen Embryo Transfer' OR 'oocyte donation' OR 'egg donation' OR 'miscarriage' OR 'pregnancy outcome' OR 'endometrium'.

OUTCOMES

During the periconceptional period (defined here as the critical time window starting 1 month before conception), estrogens play a crucial role in endometrial receptivity, through the activation of paracrine/autocrine signaling. A derailed estrogenic milieu within this period seems to be detrimental both in natural and ART-conceived pregnancies. Low estrogen levels are associated with non-conception cycles in natural pregnancies. On the other hand, excessive supraphysiologic estrogen concentrations at time of the LH peak correlate with lower live birth rates and higher risks of pregnancy complications. In early pregnancy, estrogen plays a massive role in placentation mainly by modulating angiogenic factor expression-and in the development of an immune-tolerant uterine micro-environment by remodeling the function of uterine natural killer and T-helper cells. Lower estrogen levels are thought to trigger abnormal placentation in naturally conceived pregnancies, whereas an estrogen excess seems to worsen pregnancy development and outcomes.

WIDER IMPLICATIONS

Most current evidence available endorses a relation between periconceptional and first trimester estrogen levels and pregnancy outcomes, further depicting an optimal concentration range to optimize pregnancy success. However, how estrogens co-operate with other factors in order to maintain a fine balance between local tolerance towards the developing fetus and immune responses to pathogens remains elusive. Further studies are highly warranted, also aiming to identify the determinants of estrogen response and biomarkers for personalized estrogen administration regimens in ART.

Estradiol on trigger day: Irrelevant to live birth rates of fresh cycles but positively associated with cumulative live birth rates

OBJECTIVE

To assess the effects of estradiol (E2) on trigger day on cumulative live birth rates (CLBRs), and pregnancy outcomes after fresh and frozen-thawed embryo transfer (FET).

METHODS

This multicenter retrospective cohort study included 42 315 patients from five reproductive centers. Six subgroups were divided according to E2 on trigger day (<1000, 1000-2000, 2000-3000, 3000-4000, 4000-5000, >5000 pg/mL). Smooth curve fitting and nonlinear mixed-effects models were used.

RESULTS

When E2 was <5500 pg/mL, the CLBR increased by 10% for every 1000 pg/mL increase in E2. When E2 was between 5500 and 13 281 pg/mL, CLBR increased by 1.8% for every 1000 pg/mL increase in E2. When E2 was >13 281 pg/mL, CLBR decreased by 3% for every 1000 pg/mL increase in E2. From group E2 < 1000 to group E2 > 5000 pg/mL, pregnancy and live birth rates in fresh cycles were not related to E2. The live birth rate after FET was higher in the E2 ≥ 5000 pg/mL group than in the E2 < 1000 pg/mL group (odds ratio [OR] 4.03, and 95% confidence interval [CI] 3.74-4.35; adjusted OR 1.20, 95% CI 1.05-1.37).

CONCLUSION

CLBR is associated with E2 on trigger day in a segmented manner. Pregnancy and live birth rates in fresh cycles were not associated with E2. The live birth rate in FET cycles was highest when E2 ≥ 5000 pg/mL.

The effect of peak serum estradiol level during ovarian stimulation on cumulative live birth and obstetric outcomes in freeze-all cycles

Objective

To determine whether the peak serum estradiol (E2) level during ovarian stimulation affects the cumulative live birth rate (CLBR) and obstetric outcomes in freeze-all cycles.

Methods

This retrospective cohort study involved patients who underwent their first cycle of in vitro fertilization followed by a freeze-all strategy and frozen embryo transfer cycles between January 2014 and June 2019 at a tertiary care center. Patients were categorized into four groups according to quartiles of peak serum E2 levels during ovarian stimulation (Q1-Q4). The primary outcome was CLBR. Secondary outcomes included obstetric and neonatal outcomes of singleton and twin pregnancies. Poisson or logistic regression was applied to control for potential confounders for outcome measures, as appropriate. Generalized estimating equations were used to account for multiple cycles from the same patient for the outcome of CLBR.

Results

A total of 11237 patients were included in the analysis. Cumulatively, live births occurred in 8410 women (74.8%). The live birth rate (LBR) and CLBR improved as quartiles of peak E2 levels increased (49.7%, 52.1%, 54.9%, and 56.4% for LBR; 65.1%, 74.3%, 78.4%, and 81.6% for CLBR, from the lowest to the highest quartile of estradiol levels, respectively, P<0.001). Such association remained significant for CLBR after accounting for potential confounders in multivariable regression models, whereas the relationship between LBR and peak E2 levels did not reach statistical significance. In addition, no significant differences were noticed in adverse obstetric and neonatal outcomes (gestational diabetes mellitus, pregnancy-induced hypertension, preeclampsia, placental disorders, preterm birth, low birthweight, and small for gestational age) amongst E2 quartiles for either singleton or twin live births, both before and after adjustment.

Conclusion

In freeze-all cycles, higher peak serum E2 levels during ovarian stimulation were associated with increased CLBR, without increasing the risks of adverse obstetric and neonatal outcomes.

Prediction of miscarriage in first trimester by serum estradiol, progesterone and β-human chorionic gonadotropin within 9 weeks of gestation

Purpose

To predict miscarriage outcome within 12 weeks of gestational age by evaluating values of serum estradiol, progesterone and β-human chorionic gonadotropin (β-HCG) within 9 weeks of gestation.

Methods

One hundred sixty-five women with singleton pregnancies were retrospectively studied. Estradiol, progesterone and β-HCG levels were measured at 5–6 weeks of gestation and the measurements were repeated at 7–9 weeks. According to pregnancy outcome at 12 weeks of gestation, 71 cases were categorized into miscarriage group, and 94 cases into group of normal pregnancy. Each group was further divided into 5–6 and 7–9 weeks of gestation sub-group. Predictive values of estradiol, progesterone and β- HCG levels at 5–6 weeks and 7–9 weeks of gestation were analyzed with receiver operating characteristic (ROC) curves and logistic regression.

Results

Serum levels of estradiol at 7–9 weeks identified miscarriage with an area under the ROC curve (AUC) of 0.866 (95% CI 0. 793 ~ 0.938, P = 0.000), diagnostic cutoff value of 576 pg/ml, sensitivity of 0.804, and specificity of 0.829 respectively at the optimal threshold, according to Youden index. Progesterone levels at 7–9 weeks were with AUC of 0.766 (95% CI 0. 672 ~ 0.861, P = 0.000), cutoff value of 15.27 ng/ml, sensitivity of 0.921, and specificity of 0.558, respectively; Estradiol at 5–6 weeks were with AUC of 0.709 (95% CI 0. 616 ~ 0.801, P < 0.001), the diagnostic cutoff value of 320 pg/ml, sensitivity of 0.800, and specificity of 0.574, respectively.

The performance of the dual markers of estradiol and progesterone analysis (AUC 0.871, CI 0.793–0.950), three-markers analysis (AUC 0.869, CI 0.759–0.980)were slightly better than the single marker at 7-9 weeks. β-HCG or progesterone provide additional utility of estradiol prediction at 5–6 weeks with AUC 0.770 (0.672–0.869) for β-HCG and estradiol, AUC0.768(CI 0.670–0.866) for β-HCG, estradiol and progesterone and AUC 0.739 (CI 0.651–0.827) for progesterone and estradiol.

Conclusions

Low serum levels such as dual of estradiol and progesterone or estradiol alone at 7–9 weeks, β-HCG or progesterone combing estradiol at 5–6 weeks of gestation can be used better to predict miscarriage in first trimester.

Effect of Hyperinsulinemia and Insulin Resistance on Endocrine, Metabolic, and Reproductive Outcomes in Non-PCOS Women Undergoing Assisted Reproduction: A Retrospective Cohort Study

Objective: To evaluate the effect of hyperinsulinemia (HI) and insulin resistance (IR) on endocrine, metabolic, and reproductive outcomes in women without polycystic ovary syndrome (PCOS) undergoing assisted reproduction.

Materials and Methods: The study included 1,104 non-PCOS women undergoing in vitro fertilization/intracytoplasmic sperm injection-fresh embryo transfer. HI was evaluated by serum fasting insulin (FIN), and IR was evaluated by homeostatic model assessment of insulin resistance index (HOMA-IR). In addition, biometric, sex hormone, and metabolic parameters were measured. Independent t-test, linear, and logistic regression examined associations between HI, IR, and endocrine, metabolic, ovarian stimulation characteristics, and reproductive outcomes.

Results: Women with HI and IR had lower levels of progesterone, luteinizing hormone, follicle-stimulating hormone, estradiol, high-density lipoproteins, and increased levels of triglycerides low-density lipoproteins. For ovarian stimulation characteristics, those with HI and IR had a longer duration of stimulation, a higher total gonadotropin dose, and a lower peak estradiol level. Linear regression confirmed these associations. For reproductive outcomes, HI and IR were not associated with clinical pregnancy, live birth, and miscarriage.

Conclusions: HI and IR did not impair reproductive outcomes in non-PCOS women undergoing assisted reproduction.

The Association Between Serum Estradiol Levels on hCG Trigger Day and Live Birth Rates in Non-PCOS Patients: A Retrospective Cohort Study

OBJECTIVE

To retrospectively analyze the association of serum estradiol (E2) levels on human chorionic gonadotropin (hCG) trigger day and live birth rates (LBRs) in women undergoing fresh embryo transfer and not exhibiting polycystic ovary syndrome.

DESIGN

Retrospective cohort study.

METHODS

Analysis of 13,950 patients who had fresh embryo transfer between December 2013 and December 2019. The main outcome measurement was LBRs. Multivariable regression analysis was performed to investigate associations between E2 levels on the hCG trigger day and LBRs. Stratification analysis was performed to test for effect modification in subgroups. Furthermore, a two-piecewise linear regression model was established to find nonlinear relationships.

RESULTS

Multivariable regression analysis showed a significant association between serum E2 levels on the hCG trigger day and LBRs, adjusting for covariates [relative risk (RR) 1.027, 95% confidence interval (CI) 1.007, 1.049]. Stratification analysis showed that the LBRs were positively associated (RR 1.052, 95% CI 1.004, 1.102) with every 1 ng/ml increase of serum E2 on the hCG trigger day for the subgroup with low antral follicle counts on the trigger day. Specifically, a two-piecewise linear regression model showed that there was a positive association (RR 1.188, 95% CI 1.057, 1.334) between serum E2 and LBR for every increase of 1 ng/ml E2 when the concentration of serum E2 was lower than 2.1 ng/ml. However, there was no significant association (RR 1.002, 95% CI 0.971, 1.032) between E2 levels and LBRs when the concentration of E2 was higher than the 2.1ng/ml inflection point.

CONCLUSIONS

Serum E2 levels on the hCG trigger day were segmentally connected with LBRs.

Clinical significance of combined detection of anti-Mullerian hormone and follicular output rate in women of late reproductive age

OBJECTIVE

This study was designed to explore the clinical significance of anti-Mullerian hormone (AMH) combined with follicular output rate (FORT) in women of late reproductive age.

METHODS

A total of 258 women (age range: 35-45 years old) who underwent pre-pregnancy examination in our hospital were collected as the research group (RG), among whom 184 were treated with in vitro fertilization-embryo transfer (IVF-ET). Concurrently, 126 women aged 24-30 years who came to our hospital for pre-pregnancy examination were enrolled as the control group (CG). AMH and FORT were detected and compared between the two groups to analyze the clinical significance of the two in women of late reproductive age.

RESULTS

Compared with the CG, AMH was decreased statistically in the RG (P<0.05). AMH was statistically higher in the regular menstrual group than in the menstrual disorder group (P<0.05), and FORT was statistically higher in the pregnancy group in comparison with the non-pregnancy group (P<0.05). AMH decreased with age (P<0.05), while FORT did not correlate with any notable difference among the three subgroups (P>0.05). High, medium and low AMH groups showed no significant difference in the number of retrieved oocytes and transplantable embryos, as well as FORT (P<0.05). A lower AMH level, was correlated with fewer number of retrieved oocytes and transplantable embryos, and higher the FORT level. Significant differences were present among the high, middle and low FORT groups regarding the number of retrieved oocytes and transplantable embryos, the clinical pregnancy rate and AMH level (P<0.05). The lower the level of FORT was, the less the number of retrieved oocytes and transplantable embryos was, the lower clinical pregnancy rate was, and the higher the AMH level was.

CONCLUSIONS

AMH decreases gradually in women with an increase of age, and FORT can effectively predict pregnancy outcome. AMH detection combined FORT is of great significance in predicting the ovarian reserve function in women of late reproductive age.

High levels estradiol affect blastocyst implantation and post-implantation development directly in mice

Background

Previous studies have demonstrated that high levels of estradiol (E2) impair blastocyst implantation through effects on the endometrium; however, whether high E2 directly affects blastocysts is not well established. The present study sought to clarify the direct impacts of high E2 levels on blastocysts in vitro.

Methods

ICR virgin albino mice were used. Using an in-vitro 8-day blastocyst culture model, immunofluorescence staining for the estrogen receptor (ER), blastocyst outgrowth assays, differential staining and TUNEL assays of blastocysts, and embryo transfer, we investigated the main outcomes of exposure to different E2 concentrations (10⁻⁷ to 10⁻⁴ M) in vitro and in vivo.

Results

ERα and ERβ expression were detected in pre-implantation stage embryos. In vitro exposure of blastocysts to 10⁻⁴ M E2 for 24 h followed by 7 days culture in the absence of E2 caused severe inhibition of implantation and post-implantation development. The late adverse effects of E2 on post-implantation development still occurred at concentrations of 10⁻⁷ to 10⁻⁵ M. In addition, blastocyst proliferation was reduced and apoptotic cells were increased following exposure to 10⁻⁴ M E2. Using an in vivo embryo-transfer model, we also showed that treatment with high E2 resulted in fewer implantation sites (38% vs. 72% in control) and greater resorption of implanted blastocysts (81% vs. 38% in control).

Conclusion

Exposure to high E2 concentrations in vitro is deleterious to blastocyst implantation and early post-implantation development, mainly owing to direct impacts of E2 on implanting blastocysts. In clinical assisted reproductive technique (ART), high serum E2 concentrations not only affects the endometrium, but also affects blastocysts directly at the period of implantation.

Total follicle stimulating hormone dose is negatively correlated with live births in a donor/recipient model with fresh transfer: an analysis of 8,627 cycles from the Society for Assisted Reproductive Technology Registry

OBJECTIVE

Oocyte donation has optimized our understanding of ovarian stimulation. Increasing the follicle-stimulating hormone (FSH) dose has been shown to adversely affect live birth rates in autologous cycles. Our objective is to assess whether this relationship holds true within the donor/recipient population.

DESIGN

Retrospective cohort study.

SETTING

Not applicable.

PATIENTS

Data from 2014-2016 included 8,627 fresh donor cycles.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Live birth, clinical pregnancy, and miscarriage rates.

RESULTS

The mean donor age ± standard deviation (SD) was 25.8 ± 2.8 years. Donors underwent a median of 16 days (interquartile range [IQR] 12, 19) of stimulation with a median (IQR) total FSH dose and daily dose of 2,350.0 (1,800.0, 3,025.0) and 153.8 (113.2, 205.0) IU, respectively. The live birth rate was 56.7% per transfer. For every 500-unit increase in FSH dose, there was a 3% reduction in the odds of a live birth (odds ratio [OR] 0.97; 95% confidence interval 0.95, 0.99), and a 3% reduction in the odds of a clinical pregnancy (OR 0.97; 95% confidence interval 0.95, 0.99). Days of stimulation and average daily dose were not significantly associated with live birth or clinical pregnancy. No significant association was found between miscarriage rates and total FSH dose, days of stimulation, or average daily dose.

CONCLUSION

This is a novel report of a negative association of total FSH dosage on fresh IVF live births, performed in the donor population to control for oocyte source and endometrial receptivity.

Aromatase Inhibitors for Ovarian Stimulation in Patients with Breast Cancer

BACKGROUND

Breast cancer is the most common malignancy diagnosed in women, and its treatment has a high probability of loss of fertility. Oocyte vitrification is the most commonly used technique to preserve fertility before starting oncological treatment. Aromatase inhibitors induce hypoestrogenemia while promoting the release of gonadotropins and constitute an alternative drug for ovarian stimulation in patients with breast cancer.

OBJECTIVE

In this mini-review, we update and describe the current status of aromatase inhibitor use in controlled ovarian stimulation for oocyte vitrification in patients with breast cancer.

RESULTS

Aromatase inhibitors are commonly used in combination with gonadotropins for ovarian stimulation in patients with breast cancer who preserve their fertility through oocyte vitrification. They achieve similar ovarian responses as conventional ovarian stimulation protocols in regards to the number of oocytes, and no additional complications after their use have been reported. Furthermore, aromatase inhibitors seem to be safe not only for offspring, as no more congenital defects occur in newborns from pregnancies achieved after their use, but also for the patients, as no more malignancy recurrence or increased mortality was found in cohort studies.

CONCLUSION

Aromatase inhibitors are elective drugs for ovarian stimulation in patients with breast cancer who decide to preserve their fertility through oocyte vitrification.

Cumulative Live Birth Rates After the First ART Cycle Using Flexible GnRH Antagonist Protocol vs. Standard Long GnRH Agonist Protocol: A Retrospective Cohort Study in Women of Different Ages and Various Ovarian Reserve

Objective: To compare the cumulative live birth rates (cLBRs) after the first assisted reproductive technology (ART) cycle using flexible gonadotropin releasing hormone (GnRH)-antagonist protocol vs. standard long GnRH agonist protocol for controlled ovarian stimulation (COS) in infertile women with different ages and ovarian reserve. Methods: Women who underwent ART treatment at our center between June 1st, 2015 and December 31st, 2018 were screened. Among them, only women who underwent their first COS cycle with flexible GnRH antagonist protocol or standard long GnRH agonist protocol were included in this study. The main outcome measurement was cLBR. Results: A total of 4,402 patients were eligible for the analysis, of whom, 2,762 patients used the GnRH agonist protocol and 1,640 patients used the GnRH antagonist protocol. The cLBRs of women in the antagonist protocol group and long agonist protocol group were 45.3 and 50.0%, respectively. Subgroup multivariable regression analysis showed that, in patients with low ovarian reserve (AFC ≤ 7), the cLBR was significantly lower in the antagonist group than in the long agonist protocol group [OR (95% CI) 0.62 (0.41, 0.94)], which effect was more robust in younger patients (<30 y) [OR (95% CI) 0.29 (0.11, 0.74)]. The analysis also revealed remarkably lower cLBR in patients above 40 years regardless of their AFC, although the difference was not statistically significant. However, in patients with high ovarian reserve (AFC >24), the cLBR was higher in cycles with antagonist protocol than with the long agonist protocol [OR (95% CI) 1.43 (0.96, 2.12)], and the effect was of statistical significance in younger patients (< 30 y) [OR (95% CI) 1.78 (1.07, 2.96)]. Conclusion: The present study suggests that the flexible GnRH antagonist protocol might not be suitable for patients with low ovarian reserve (AFC ≤ 7) or patients aged over 40 years. However, flexible GnRH antagonist protocol might be strongly recommended for patients under 30 years old and with high ovarian reserve (AFC > 24). For the rest groups of patients in the present cohort, antagonist protocol was slightly favored because it had lower OHSS in general and in patients with poly-cystic ovarian syndrome (PCOS) according to previous publications.