Transcriptomic Analysis Reveals Endometrial Dynamics in Normoweight and Overweight/Obese Polycystic Ovary Syndrome Women

Association between body mass index and in vitro fertilization/intra-cytoplasmic sperm injection outcomes: An analysis of 15,124 normal ovarian responders in China

BACKGROUND

High body mass index (BMI) results in decreased fecundity, and women with high BMI have reduced rates of clinical pregnancy and live birth in in vitro fertilization/intra-cytoplasmic sperm injection (IVF/ICSI). Meanwhile, ovarian responses show great heterogeneity in patients with a high BMI. This study aimed to analyze the effects of a high BMI on IVF/ICSI outcomes in the Chinese female with normal ovarian response.

METHODS

We performed a retrospective cohort study comprising 15,124 patients from the medical record system of the Reproductive Center of Peking University Third Hospital, with 3530 (23.3%) in the overweight group and 1380 (9.1%) in the obese group, who had a normal ovarian response (5-15 oocytes retrieved) and underwent fresh embryo transfer (ET) cycles from January 2017 to December 2018, followed by linked frozen-thawed embryo transfer (FET) cycles from January 2017 to December 2020. Cumulative live birth rate (CLBR) was used as the primary outcome. Furthermore, a generalized additive model was applied to visually illustrate the curvilinear relationship between BMI and the outcomes. We used a decision tree to identify the specific population where high BMI had the greatest effect on IVF/ICSI outcomes.

RESULTS

High BMI was associated with poor IVF/ICSI outcomes, both in cumulative cycles and in separate fresh ET or FET cycles. In cumulative cycles, compared with the normal weight group, obesity was correlated with a lower positive pregnancy test rate (adjusted odds ratio [aOR]: 0.809, 95% confidence interval [CI]: 0.682-0.960), lower clinical pregnancy rate (aOR: 0.766, 95% CI: 0.646-0.907), lower live birth rate (aOR: 0.706, 95% CI: 0.595-0.838), higher cesarean section rate (aOR: 2.066, 95% CI: 1.533-2.785), and higher rate of large for gestational age (aOR: 2.273, 95% CI: 1.547-3.341). In the generalized additive model, we found that CLBR declined with increasing BMI, with 24 kg/m 2 as an inflection point. In the decision tree, BMI only made a difference in the population aged ≤34.5 years, with anti-Mullerian hormone >1.395 ng/mL, and the first time for IVF.

CONCLUSIONS

High BMI was related to poor IVF/ICSI outcomes in women with a normal ovarian response, and CLBR declined with increasing BMI, partly due to suppressed endometrial receptivity. A high BMI had the most negative effect on young women with anticipated positive prognoses.

Hyperinsulinemia impairs decidualization via AKT-NR4A1 signaling: new insight into polycystic ovary syndrome (PCOS)-related infertility

BACKGROUND

Investigating the underlying molecular mechanisms responsible for endometrial dysfunction in women with PCOS is essential, particularly focusing on the role of hyperinsulinemia.

METHODS

We explored the role of insulin in the decidualization process using a synthetic decidualization assay. To dissect the effects of PI3K/AKT-NR4A signaling, we employed small interfering RNAs (siRNAs) targeting the NR4A genes and inhibitors of the PI3K/AKT pathway. We also investigated the disruption of AKT-NR4A1 signaling in the endometrium of PCOS female rats induced with dehydroepiandrosterone (DHEA). Quantitative real-time PCR (qRT-PCR) and Western blot (WB) analyses were utilized to evaluate gene expression regulation.

RESULTS

Insulin was found to suppress the expression of decidualization markers in human endometrial stromal cells (hESC) in a dose-dependent manner, concurrently triggering an inappropriate activation of the PI3K/AKT pathway. Members of the NR4A family, as downstream effectors in the PI3K/AKT pathway, were implicated in the insulin-induced disruptions during the decidualization process. Moreover, the endometrium of PCOS models showed significantly elevated levels of phosphorylated (Ser473) AKT, with a corresponding reduction in Nr4a1 protein.

CONCLUSIONS

Our research demonstrates that insulin negatively regulates decidualization in hESC via the PI3K/AKT-NR4A pathway. In vivo analysis revealed a significant dysregulation of the AKT-NR4A1 pathway in the endometrium of PCOS rats. These findings offer novel insights into the pathogenesis of infertility and endometrial disorders associated with hyperinsulinemia in PCOS.

Ultrasound‑assessed endometrial receptivity measures for the prediction of in vitro fertilization‑embryo transfer clinical pregnancy outcomes: A meta‑analysis and systematic review

At present, there are currently no reliable and consistent conclusions regarding transvaginal ultrasound assessment of endometrial receptivity in predicting clinical pregnancy outcomes of in vitro fertilization-embryo transfer (IVF-ET). Thus, in the present study, a meta-analysis was performed on multiple endometrial receptivity indices detected by vaginal ultrasound, aiming to provide a diagnostic basis for clinical practice. PubMed, Embase, and Cochrane Library databases were searched for studies published between the establishment of the databases through to January 2023. Studies that reported infertile women undergoing IVF-ET and undergoing vaginal ultrasound were included, but repeat publication, studies where the full text was not obtainable, studies where there was incomplete information provided or data extraction was not possible, studies on animals, case reports, reviews, and systematic reviews were excluded. STATA 15.1 was used to analyze the data. The pooled results showed that the endometrial thickness [Weighted mean difference (WMD)=0.03, 95% CI: 0.00-0.06; P=0.022] and endometrial volume (WMD=0.41, 95% CI: 0.07-0.74; P=0.017) of the pregnancy group after receiving IVF-ET were all significantly higher than that of the non-pregnancy group. The pooled results also showed that the vascularization index (VI) (WMD=0.79, 95% CI: 0.56-1.03; P=0.000), flow index (FI) (WMD=1.82, 95% CI: 0.83-2.81; P=0.000) and vascularization flow index (VFI) (WMD=1.58, 95% CI: 0.91-2.24; P=0.000) of the pregnancy group after receiving IVF-ET was significantly higher than that of the non-pregnancy group. Systolic/diastolic (S/D) (WMD=-4.92, 95%CI: -8.28- -1.56; P=0.004) of the uterine artery of the pregnancy group after receiving IVF-ET was significantly lower than that of the non-pregnancy group. However, the differences between the resistance index (RI) and pulsatility index (PI) in the pregnancy group vs. the non-pregnancy group after receiving IVF-ET were not statistically significant. Vaginal ultrasound can be used to predict the outcomes of pregnancy in infertile women undergoing IVF-ET by measuring the thickness and volume of the endometrium, combined with the S/D, VI, FI, and VFI of the uterine artery.