Causal associations between Helicobacter pylori infection and pregnancy and neonatal outcomes: a two-sample Mendelian randomization study.

Background: Observational studies have reported that Helicobacter pylori (H. pylori) infection is associated with a series of pregnancy and neonatal outcomes. However, the results have been inconsistent, and the causal effect is unknown. Methods: A two-sample Mendelian randomization (MR) study was performed using summary-level statistics for anti-H. pylori IgG levels from the Avon Longitudinal Study of Parents and Children Cohort. Outcome data for pregnancy (miscarriage, preeclampsia-eclampsia, gestational diabetes mellitus, placental abruption, premature rupture of membranes, postpartum hemorrhage) and neonates (birthweight, gestational age, and preterm birth) were sourced from genome-wide association meta-analysis as well as the FinnGen and Early Growth Genetics Consortium. Causal estimates were calculated by five methods including inverse variance weighted (IVW). The heterogeneity of instrumental variables was quantified by Cochran's Q test, while sensitivity analyses were performed via MR-Egger, MR-PRESSO, and leave-one-out tests. Results: IVW estimates suggested that genetically predicted anti-H. pylori IgG levels were significantly associated with increased risks of preeclampsia-eclampsia (odds ratio [OR] = 1.12, 95% confidence interval [CI] 1.01-1.24, P = 0.026) and premature rupture of membranes (OR = 1.17, 95% CI 1.05-1.30, P = 0.004). Similar results were obtained for preeclampsia-eclampsia from the MR-Egger method (OR = 1.32, 95% CI 1.06-1.64, P = 0.027) and for premature rupture of membranes from the weighted median method (OR = 1.22, 95% CI 1.06-1.41, P = 0.006). No significant causal effects were found for other outcomes. There was no obvious heterogeneity and horizontal pleiotropy across the MR analysis. Conclusion: Our two-sample MR study demonstrated a causal relationship of H. pylori infection with preeclampsia-eclampsia and premature rupture of membranes. The findings confirm the epidemiological evidence on the adverse impact of H. pylori in pregnancy. Further studies are needed to elucidate the pathophysiological mechanisms and assess the effectiveness of pre-pregnancy screening and preventive eradication.

Transcriptomic responses of cumulus granulosa cells to SARS-CoV-2 infection during controlled ovarian stimulation.

Cumulus granulosa cells (CGCs) play a crucial role in follicular development, but so far, no research has explored the impact of SARS-CoV-2 infection on ovarian function from the perspective of CGCs. In the present study, we compared the cycle outcomes between infected and uninfected female patients undergoing controlled ovarian stimulation, performed bulk RNA-sequencing of collected CGCs, and used bioinformatic methods to explore transcriptomic changes. The results showed that women with SARS-CoV-2 infection during stimulation had significantly lower number of oocytes retrieved and follicle-oocyte index, while subsequent fertilization and embryo development were similar. CGCs were not directly infected by SARS-CoV-2, but exhibited dramatic differences in gene expression (156 up-regulated and 65 down-regulated). Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses demonstrated a high enrichment in antiviral, immune and inflammatory responses with necroptosis. In addition, the pathways related to telomere organization and double strand break repair were significantly affected by infection in gene set enrichment analysis. Further weighted gene co-expression network analysis identified a key module associated with ovarian response traits, which was mainly enriched as a decrease of leukocyte chemotaxis and migration in CGCs. For the first time, our study describes how SARS-CoV-2 infection indirectly affects CGCs at the transcriptional level, which may impair oocyte-CGC crosstalk and consequently lead to poor ovarian response during fertility treatment.

Pregnancy outcomes after frozen-thawed embryo transfer in women with COVID-19 history: A prospective cohort study.

The clinical effect of Coronavirus disease 2019 (COVID-19) on endometrial receptivity and embryo implantation remains unclear. Herein, we aim to investigate whether a COVID-19 history adversely affect female pregnancy outcomes after frozen-thawed embryo transfer (FET). This prospective cohort study enrolled 230 women who underwent FET cycles from December 2022 to April 2023 in an academic fertility center. Based on the history of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection before FET, women were divided into the infected group (n = 136) and the control group (n = 94). The primary outcome was the clinical pregnancy rate per cycle. Multivariate logistic regression analysis was conducted to adjust for potential confounders, while subgroup analysis and restricted cubic splines were used to depict the effect of postinfection time interval on FET. The results showed that the clinical pregnancy rate was 59.6% in the infected group and 63.9% in the control group (p = 0.513). Similarly, the two groups were comparable in the rates of biochemical pregnancy (69.1% vs. 76.6%; p = 0.214) and embryo implantation (51.7% vs. 54.5%; p = 0.628). After adjustment, the nonsignificant association remained between prior infection and clinical pregnancy (OR = 0.78, 95% CI: 0.42-1.46). However, the odds for clinical pregnancy were significantly lower in the ≤30 days subgroup (OR = 0.15, 95% CI: 0.03-0.77), while no statistical significance was detected for 31-60 days and >60 days subgroups compared with the uninfected women. In conclusion, our findings suggested that SARS-CoV-2 infection in women had no significant effect on subsequent FET treatment overall, but pregnancy rates tended to be decreased if vitrified-thawed embryos were transferred within 30 days after infection. A 1-month postponement should be rationally recommended, while further studies with larger sample groups and longer follow-up periods are warranted for confirmation.

Reduced PATL2 Impairs the Proliferation of Ovarian Granulosa Cells by Decreasing ADM2 Expression in Patients with PCOS.

It is recognized that PCOS patients are often accompanied with aberrant follicular development, which is an important factor leading to infertility in patients. However, the relevant regulatory mechanisms of abnormal follicular development are not well understood. In the present study, by collecting human ovarian granulosa cells (GCs) from PCOS patients who underwent in vitro fertilization (IVF), we found that the proliferation ability of GCs in PCOS patients was significantly reduced. Surprisingly, PATL2 and adrenomedullin 2 (ADM2) were obviously decreased in the GCs of PCOS patients. To further explore the potential roles of PATL2 and ADM2 on GC, we transfected PATL2 siRNA into KGN cells to knock down the expression of PATL2. The results showed that the growth of GCs remarkably repressed after knocking down the PATL2, and ADM2 expression was also weakened. Subsequently, to study the relationship between PATL2 and ADM2, we constructed PATL2 mutant plasmid lacking the PAT construct and transfected it into KGN cells. The cells showed the normal PATL2 expression, but attenuated ADM2 expression and impaired proliferative ability of GCs. Finally, the rat PCOS model experiments further confirmed our findings in KGN cells. In conclusion, our study suggests that PATL2 promoted the proliferation of ovarian GCs by stabilizing the expression of ADM2 through "PAT" structure, which is beneficial to follicular development, whereas, in the ovary with polycystic lesions, reduction of PATL2 could result in the decreased expression of ADM2, subsequently weakened the proliferation ability of GCs and finally led to the occurrence of aberrant follicles.

Effect of prior female SARS-CoV-2 infection on IVF outcomes: a prospective cohort study.

Introduction: The clinical impact of SARS-CoV-2 infection on human reproduction remains controversial. This prospective cohort study aimed to assess the effect of prior female SARS-CoV-2 infection on subsequent in vitro fertilization (IVF) outcomes. Materials and methods: A total of 451 women who underwent fresh IVF treatment between December 1, 2022 and April 30, 2023 were included from an academic fertility center. Participants were divided into the infected group if they had a prior COVID-19 history before cycle initiation (n = 252), while the control group were those uninfected (n = 199). The primary outcomes were the number of oocytes retrieved and clinical pregnancy rate after fresh embryo transfer. Multivariate linear and logistic regression analyses were conducted to control for potential confounders. Results: The number of oocytes retrieved (11.4 ± 8.3 vs. 11.6 ± 7.7; P = 0.457) and clinical pregnancy rate (70.3% vs. 73.7%; P = 0.590) were similar between infected and uninfected groups, with a fully adjusted ß coefficient of 0 (95% confidence interval [CI]: -0.14-0.13) and odds ratio of 0.64 (95% CI: 0.20-2.07), respectively. Consistently, the two groups were comparable in cycle characteristics as well as other laboratory and pregnancy parameters. In both subgroup analyses and restricted cubic splines, different post-infection time intervals to IVF cycle initiation showed no significant associations with treatment outcomes. Conclusion: Prior SARS-CoV-2 infection in females had no adverse influence on subsequent IVF treatment, regardless of the time interval following infection. Our findings provide reassurance for infected women planning for assisted reproduction. Additional prospective cohort studies with larger datasets and longer follow-up are required to confirm the conclusion.

Impact of inactivated COVID-19 vaccination on female ovarian reserve: a propensity score-matched retrospective cohort study.

Purpose: To explore the impact of inactivated COVID-19 vaccination on ovarian reserve as assessed by serum anti-Müllerian hormone (AMH) concentration. Methods: A total of 3160 women were included in this single-center retrospective cohort study between June 2021 and October 2022. Vaccination information were collected from official immunization records available in personal mobile apps. Serum AMH was qualified by electrochemiluminescence immunoassay and compared with previous measurement data within three years. Women were categorized to the vaccinated group if they received two doses of inactivated COVID-19 vaccines (Sinopharm or Sinovac) between AMH tests (n = 488), and to the control group if not vaccinated (n = 2672). Propensity score matching and multivariate linear regression were performed to control for potential confounders. The main outcome measures were the numeric AMH change and percentage AMH change between the two tests. Results: There were 474 women left in each group after matching all baseline characteristics. The mean interval from the first to second AMH measurement was 508.0 ± 250.2 and 507.5 ± 253.6 days for vaccinated and unvaccinated women, respectively (P = 0.680). Both groups had a significant AMH decrease in the second test compared with the first test (P = 0.001). However, the second AMH level remained comparable between groups (3.26 ± 2.80 vs. 3.24 ± 2.61 ng/mL, P = 0.757). Similarly, no significant differences were observed in numerical (-0.14 ± 1.32 vs. -0.20 ± 1.56 ng/mL, P = 0.945) and percentage (2.33 ± 58.65 vs. 0.35 ± 48.42%, P = 0.777) AMH changes. The results were consistent in sub-analyses for women aged <35 and ≥35 years. There were also no significant differences when vaccinated women were divided according to the time interval after vaccination: ≤30, 31-60, 61-90, and ≥91 days. Conclusion: Our study provides the first evidence that inactivated COVID-19 vaccination has no measurable detrimental effect on ovarian reserve, regardless of female age and vaccination interval. This reassuring finding adds to the safety evidence of COVID-19 vaccine in fertility, and should be useful to promote vaccine acceptance. Multicenter prospective cohort studies are needed to validate our conclusion.

Comparison of recombinant human FSH biosimilar QL1012 with Gonal-f® for ovarian stimulation: a phase-three trial.

RESEARCH QUESTION: Are QL1012 and Gonal-f® equivalent in women undergoing ovarian stimulation for assisted reproductive technology (ART)? DESIGN: This multicentre, randomized, assessor-blinded, phase-three trial was conducted at 13 centres in China. Eligible patients were infertile women; age 20-39 years; body mass index 18-30 kg/m2; regular menstrual cycles; and indication for ART. After successful pituitary downregulation, patients were randomly assigned (1:1) to receive QL1012 or Gonal-f®, stratified by age (initial dose of 75-150 IU for women younger than 30 years, 150-225 IU for women aged 30-34 years and 225-300 IU for women aged ≥35 years, subcutaneously, once daily). The primary end point was the number of oocytes retrieved. RESULTS: Between October 2018, and June 2019, 341 patients were included in the per-protocol set. The mean numbers of oocytes retrieved were 14.7 ± 7.0 in the QL1012 group (n = 169) and 13.4 ± 6.1 in the Gonal-f® group (n = 172). Adjusted by analysis of covariance model, the least-squares mean difference was 1.3 oocytes (95% CI -0.1 to 2.7; P = 0.0650), within the pre-defined equivalence margins of ±3.0. Similar results were observed in the full analysis set. Additionally, no statistical differences were found in secondary end points except oestradiol concentration (median 3948.0 pg/ml versus 3545.3 pg/ml; P = 0.0015). Ovarian hyperstimulation syndrome (12.4% versus 13.1 %) and other adverse events were similar between the two groups. CONCLUSIONS: Therapeutic equivalence and similar safety profiles were demonstrated between QL1012 and Gonal-f® in women undergoing ovarian stimulation for ART.

Effect of COVID-19 vaccination on semen parameters: A systematic review and meta-analysis.

The aim of this study was to investigate the effect of coronavirus disease 2019 (COVID-19) vaccination on semen parameters through systematic review and meta-analysis. PubMed, EMBASE, Web of Science, and Cochrane Library were comprehensively searched by June 2022. Studies were considered eligible if they compared semen parameters before and after COVID-19 vaccination or between vaccinated and unvaccinated men, with no restrictions on vaccine types or doses. The effect size was calculated as mean difference (MD) with 95% confidence interval (CI) using a random-effects model. Subgroup and sensitivity analyses were conducted to assess the sources of heterogeneity measured by the I2 statistic, with publication bias evaluated by Egger's test. Twelve cohort studies involving 914 participants fulfilled the inclusion criteria. In a comparison of vaccinated versus unvaccinated group, the pooled data revealed no significant differences in semen volume (MD = 0.18 ml, 95% CI -0.02 to 0.38), sperm concentration (MD = 1.16 million/ml, 95% CI -1.34 to 3.66), total sperm motility (MD = -0.14%, 95% CI -2.84 to 2.56), progressive sperm motility (MD = -1.06%, 95% CI -2.88 to 0.77), total sperm count (MD = 5.92 million, 95% CI -10.22 to 22.05), total motile sperm count (MD = 2.18 million, 95% CI -1.28 to 5.63), total progressively motile sperm count (MD = -3.87 million, 95% CI -13.16 to 5.43), and sperm morphology (MD = 0.07%, 95% CI -0.84 to 0.97). The results also remained similar across messenger ribonucleic acid, viral-vector, and inactivated COVID-19 vaccines. Sensitivity analysis identified two individual studies that contributed to heterogeneity, while the effect size was not materially altered. No obvious publication bias was detected among included studies. Our finding suggested that COVID-19 vaccination had no detrimental impact on semen quality, which could be potentially helpful to reduce male vaccine hesitancy and increase vaccination coverage.

Identification of a novel ESR1 mutation in a Chinese PCOS woman with estrogen insensitivity in IVF treatment.

BACKGROUND: Polycystic ovary syndrome (PCOS) is a complex reproductive disorder, that affects approximately 5-10% of women of reproductive age. The disease is complex because its evolution may be impacted by genetic, lifestyle and environmental factors. Previous studies have emphasized the important roles of estrogen receptors in the pathogenesis of PCOS. OBJECTIVE: To use whole exome sequencing (WES) to assess possible pathogenic factors in a PCOS patient who exhibited estrogen insensitivity during hormone replacement therapy (HRT) treatment. METHODS: Genome sequencing and variant filtering via WES were performed in a patient with PCOS. DNA extraction from 364 unrelated female controls without PCOS was followed by PCR amplification, Sanger sequencing and sequence alignment. Evolutionary conservation analysis, protein structural modelling and in silico prediction were applied to analyse the potential pathogenicity of the novel ESR1 mutation. RESULT(S): During the controlled ovarian hyperstimulation (COH) period of an IVF cycle, the patient experienced markedly prolonged ovarian stimulation due to a poor response to gonadotropins (Gn) and elevated serum FSH. A novel heterozygous ESR1 mutation, c.619G > A/p.A207T, leading to the replacement of a highly conserved alanine with a threonine, was identified in this patient, via WES analysis. This novel variant was not identified in 364 unrelated female controls without PCOS, or in the Exome Aggregation Consortium (ExAC) or 1000 Genome Project. CONCLUSION(S): We identified a novel heterozygous ESR1 mutation in a Han Chinese PCOS woman exhibiting clinical signs of estrogen insensitivity. This study may provide new strategies for IVF therapy, especially for patients who exhibit estrogen insensitivity during IVF cycle.

Aberrant BMP15/HIF-1α/SCF signaling pathway in human granulosa cells is involved in the PCOS related abnormal follicular development.

AIMS: To investigate the regulatory mechanism of SCF expression in human GCs of PCOS related follicles. MATERIALS AND METHODS: SCF, BMP15 and HIF-1α were evaluated in human serums, follicular fluids (FFs) and GCs, which were collected from 69 PCOS patients and 74 normal ovulatory patients. KGN cell line was used in this study. RESULTS: Our results showed that the rate of MII oocyte and 2PN fertilization was lower in PCOS group, though PCOS patients retrieved much more oocytes. The level of BMP15 in FF and the level of SCF in serum and FF were also lower in PCOS patients. We found a weakened expression of HIF-1α and SCF in GCs from PCOS patients when compared with the non-PCOS patients. The expression of HIF-1α and SCF was significantly increased in KGN cells after treating cells with rhBMP15, however, this promotion effects of BMP15 on HIF-1α and SCF expression were obviously abolished by co-treatment with BMP-I receptor inhibitor (DM). Moreover, knock down of HIF-1α expression in KGN cells significantly reduced the expression of SCF in human GCs, in spite of activating BMP15 signaling pathway. CONCLUSIONS: The present study suggest that BMP15 could induce SCF expression by up-regulating HIF-1α expression in human GCs, the aberrance of this signaling pathway might be involved in the PCOS related abnormal follicular development.

Impact of inactivated SARS-CoV-2 vaccination on embryo ploidy: a retrospective cohort study of 133 PGT-A cycles in China.

BACKGROUND: Unsubstantiated concerns have been raised on the potential correlation between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination and infertility, leading to vaccine hesitancy in reproductive-aged population. Herein, we aim to evaluate the impact of inactivated SARS-CoV-2 vaccination on embryo ploidy, which is a critical indicator for embryo quality and pregnancy chance. METHODS: This was a retrospective cohort study of 133 patients who underwent preimplantation genetic testing for aneuploidy (PGT-A) cycles with next-generation sequencing technology from June 1st 2021 to March 17th 2022 at a tertiary-care medical center in China. Women fully vaccinated with two doses of Sinopharm or Sinovac inactivated vaccines (n = 66) were compared with unvaccinated women (n = 67). The primary outcome was the euploidy rate per cycle. Multivariate linear and logistic regression analyses were performed to adjust for potential confounders. RESULTS: The euploidy rate was similar between vaccinated and unvaccinated groups (23.2 ± 24.6% vs. 22.6 ± 25.9%, P = 0.768), with an adjusted ß of 0.01 (95% confidence interval [CI]: -0.08-0.10). After frozen-thawed single euploid blastocyst transfer, the two groups were also comparable in clinical pregnancy rate (75.0% vs. 60.0%, P = 0.289), with an adjusted odds ratio of 6.21 (95% CI: 0.76-50.88). No significant associations were observed between vaccination and cycle characteristics or other laboratory and pregnancy outcomes. CONCLUSIONS: Inactivated SARS-CoV-2 vaccination had no detrimental impact on embryo ploidy during in vitro fertilization treatment. Our finding provides further reassurance for vaccinated women who are planning to conceive. Future prospective cohort studies with larger datasets and longer follow-up are needed to confirm the conclusion.

A novel heterozygous variant in PANX1 is associated with oocyte death and female infertility.

PURPOSE: Oocyte death is a severe clinical phenotype that causes female infertility and recurrent in vitro fertilization and intracytoplasmic sperm injection failure. We aimed to identify pathogenic variants in a female infertility patient with oocyte death phenotype. METHODS: Sanger sequencing was performed to screen PANX1 variants in the affected patient. Western blot analysis was used to check the effect of the variant on PANX1 glycosylation pattern in vitro. RESULTS: We identified a novel PANX1 variant (NM_015368.4 c.86G > A, (p. Arg29Gln)) associated with the phenotype of oocyte death in a non-consanguineous family. This variant displayed an autosomal dominant inheritance pattern with reduced penetrance. Western blot analysis confirmed that the missense mutation of PANX1 (c.86G > A) altered the glycosylation pattern in HeLa cells. Moreover, the mutation effects on the function of PANX1 were weaker than recently reported variants. CONCLUSION: Our findings expand the inheritance pattern of PANX1 variants to an autosomal dominant mode with reduced penetrance and enrich the variational spectrum of PANX1. These results help us to better understand the genetic basis of female infertility with oocyte death.

GnRH antagonist weakens endometrial stromal cells growth ability by decreasing c-kit receptor expression.

BACKGROUND: Several surveys have reported that patients treated with gonadotropin-releasing hormone antagonist (GnRH-ant) protocol showed a significantly lower rate of implantation and clinical pregnancy compared to GnRH agonist (GnRH-a) protocol during in vitro fertilization-fresh embryo transfer. Subsequent studies imputed this poor outcome to the negative effects of GnRH-ant on endometrial receptive. However, the mechanisms were not fully understood. METHODS: The clinical data of 2815 patients undergoing fresh embryo transfer in our center were analyzed. Human endometrial stromal cells (ESCs) from healthy women undergoing elective pregnancy termination of a normal pregnancy at 8-10 weeks gestation were treated with GnRH-analogs or imatinib (c-kit receptor inhibitor). CCK8 and Flow cytometry were used to investigated the growth ability of ESCs. Immunofluorescence staining and western blot was used to detected the target proteins. RESULTS: The clinical data showed that the endometrial thickness on HCG Day were significantly lower in GnRH-ant group. Although no difference of embryo quality in these two groups, GnRH-ant group showed remarkably decreased rate of HCG positive, embryo implantation and pregnancy. Moreover, GnRH-ant significantly reduced the proliferation and induced the apoptosis of ESCs. Furthermore, the expression and activation of c-kit receptor, which played pivotal roles during embryo implantation, were observably decreased by GnRH-ant. Inhibiting the activation of c-kit by imatinib remarkably suppressed the proliferation and promoted the apoptosis of ESCs. Additionally, the phosphorylation of AKT and expression of Cyclin D1, which were closely related with cellular growth, were distinctly lessened after treating with imatinib. CONCLUSIONS: In summary, our study showed that GnRH-ant weakened the activization of c-kit receptor by decreasing its expression, causing the impaired growth ability of ESCs. Our findings provided a new insight into the effects of GnRH-ant on endometrium.

Impact of inactivated SARS-CoV-2 vaccination on embryo ploidy: a retrospective cohort study of 133 PGT-A cycles in China

BACKGROUND: Unsubstantiated concerns have been raised on the potential correlation between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination and infertility, leading to vaccine hesitancy in reproductive-aged population. Herein, we aim to evaluate the impact of inactivated SARS-CoV-2 vaccination on embryo ploidy, which is a critical indicator for embryo quality and pregnancy chance. METHODS: This was a retrospective cohort study of 133 patients who underwent preimplantation genetic testing for aneuploidy (PGT-A) cycles with next-generation sequencing technology from June 1st 2021 to March 17th 2022 at a tertiary-care medical center in China. Women fully vaccinated with two doses of Sinopharm or Sinovac inactivated vaccines (n = 66) were compared with unvaccinated women (n = 67). The primary outcome was the euploidy rate per cycle. Multivariate linear and logistic regression analyses were performed to adjust for potential confounders. RESULTS: The euploidy rate was similar between vaccinated and unvaccinated groups (23.2 ± 24.6% vs. 22.6 ± 25.9%, P = 0.768), with an adjusted ß of 0.01 (95% confidence interval [CI]: -0.08-0.10). After frozen-thawed single euploid blastocyst transfer, the two groups were also comparable in clinical pregnancy rate (75.0% vs. 60.0%, P = 0.289), with an adjusted odds ratio of 6.21 (95% CI: 0.76-50.88). No significant associations were observed between vaccination and cycle characteristics or other laboratory and pregnancy outcomes. CONCLUSIONS: Inactivated SARS-CoV-2 vaccination had no detrimental impact on embryo ploidy during in vitro fertilization treatment. Our finding provides further reassurance for vaccinated women who are planning to conceive. Future prospective cohort studies with larger datasets and longer follow-up are needed to confirm the conclusion.

Decreased Endometrial Thickness Is Associated With Higher Risk of Neonatal Complications in Women With Polycystic Ovary Syndrome.

Purpose: To evaluate the association of endometrial thickness (EMT) with obstetric and neonatal outcomes in women with polycystic ovary syndrome (PCOS). Methods: A total of 1755 subfertile PCOS women with singleton livebirths after frozen-thawed embryo transfer were included between January 2009 and September 2019. Main obstetric outcomes were hypertensive disorders in pregnancy and abnormal placentation. Main neonatal outcomes were preterm birth (PTB), low birthweight (LBW) and small-for-gestational age (SGA). Crude and adjusted odds ratios (ORs) with 95% confidence intervals (CIs) were estimated by univariate and multivariate logistic regression analyses. Results: Each millimeter decrease in EMT was related to a 9% (adjusted OR 1.09, 95% CI 1.00-1.19; P = 0.053), 14% (adjusted OR 1.14, 95% CI 1.02-1.28; P = 0.002) and 22% (adjusted OR 1.22, 95% CI 1.07-1.38; P = 0.003) higher risk of PTB, LBW and SGA, respectively. Compared to women with EMT >13 mm, women with EMT ≤8 mm also had significantly higher risk of PTB (adjusted OR 3.79, 95% CI 1.53-9.39; P = 0.004), LBW (adjusted OR 4.33, 95% CI 1.39-13.50; P = 0.012) and SGA (adjusted OR 6.38, 95% CI 1.78-22.83; P = 0.004). These associations remained consistent in further subgroup analysis by endometrial preparation regimen and in sensitivity analyses among nulligravida women or women without adverse obstetric outcomes. No significant differences were found in the incidence of several pregnancy complications across EMT categories. Conclusion: Decreased EMT was independently associated with increased risk of PTB, LBW and SGA in women with PCOS.

Mild starting dosage ovarian stimulation combined with a modified prolonged GnRH-a protocol improved IVF/ICSI outcomes in normal ovarian responders.

INTRODUCTION: Controlled ovarian hyperstimulation (COH) is essential for artificial reproduction technology (ART). This study aimed to evaluate the effects of a mild starting dosage of r-FSH ovarian stimulation after the modified prolonged GnRH-a down-regulation protocol for COH on the clinical outcomes in normal ovarian responders undergoing in vitro fertilization/intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET). MATERIAL AND METHODS: In the retrospective study, the patients were separated into two groups according to the starting dosage of r-FSH: a mild dosage group (75 IU ≤ r-FSH < 150 IU, n = 858) and a conventional dosage group (150 IU ≤ r-FSH ≤ 225 IU, n = 535). Data were collected from clinical records. The baseline characteristics and clinical outcomes were compared between the two groups. RESULTS: Although the duration of r-FSH treatment was a little longer in the mild dosage group, the total r-FSH dosage and the cost of ovarian stimulation were significantly lower than those in the conventional dosage group. Furthermore, compared to the conventional dosage group, the number of retrieved oocytes was also lower in the mild dosage group, whereas the rates of two pronuclei (2PN) fertilized oocytes and good-quality embryos were remarkable higher. The implantation rate, clinical pregnancy rate and live birth rate were significantly higher in the mild dosage group. There was no difference in early miscarriages rate, incidence of moderate and severe ovarian hyper-stimulation syndrome (OHSS) or incidence of ectopic pregnancy between the two groups. CONCLUSIONS: The modified prolonged GnRH-a pituitary down-regulation regimen combined with mild r-FSH starting dosage improved IVF/ICSI outcomes and reduced the financial cost in normal ovarian responders.