A sonographic endometrial thickness <7 mm in women undergoing in vitro fertilization increases the risk of placenta accreta spectrum.

BACKGROUND: The prevalence of placenta accreta spectrum, a potentially life-threatening condition, has exhibited a significant global rise in recent decades. Effective screening methods and early identification strategies for placenta accreta spectrum could enable early treatment and improved outcomes. Endometrial thickness plays a crucial role in successful embryo implantation and favorable pregnancy outcomes. Extensive research has been conducted on the impact of endometrial thickness on assisted reproductive technology cycles, specifically in terms of pregnancy rates, live birth rates, and pregnancy loss rates. However, limited knowledge exists regarding the influence of endometrial thickness on placenta accreta spectrum. OBJECTIVE: This study aimed to evaluate the association between preimplantation endometrial thickness and the occurrence of placenta accreta spectrum in women undergoing assisted reproductive technology cycles. STUDY DESIGN: A total of 4637 women who had not undergone previous cesarean delivery and who conceived by in vitro fertilization or intracytoplasmic sperm injection-embryo transfer treatment and subsequently delivered at the Third Affiliated Hospital of Guangzhou Medical University between January 2008 and December 2020 were included in this study. To explore the relationship between endometrial thickness and placenta accreta spectrum, we used smooth curve fitting, threshold effect, and saturation effect analysis. Multivariate logistic regression analysis was performed to evaluate the independent association between endometrial thickness and placenta accreta spectrum while adjusting for potential confounding factors. Propensity score matching was performed to reduce the influence of bias and unmeasured confounders. Furthermore, we used causal mediation effect analysis to investigate the mediating role of endometrial thickness in the relationship between gravidity and ovarian stimulation protocol and the occurrence of placenta accreta spectrum. RESULTS: Among the 4637 women included in this study, pregnancies with placenta accreta spectrum (159; 3.4%) had significantly thinner endometrial thickness (non-placenta accreta spectrum, 10.08±2.04 mm vs placenta accreta spectrum, 8.88±2.21 mm; P<.001) during the last ultrasound before embryo transfer. By using smooth curve fitting, it was found that changes in endometrial thickness had a significant effect on the incidence of placenta accreta spectrum up to a thickness of 10.9 mm, beyond which the effect plateaued. Then, the endometrial thickness was divided into the following 4 groups: ≤7, >7 to ≤10.9, >10.9 to ≤13, and >13 mm. The absolute rates of placenta accreta spectrum in each group were 11.91%, 3.73%, 1.35%, and 2.54%, respectively. Compared with women with an endometrial thickness from 10.9 to 13 mm, the odds of placenta accreta spectrum increased from an adjusted odds ratio of 2.27 (95% confidence interval, 1.33-3.86) for endometrial thickness from 7 to 10.9 mm to an adjusted odds ratio of 7.15 (95% confidence interval, 3.73-13.71) for endometrial thickness <7 mm after adjusting for potential confounding factors. Placenta previa remained as an independent risk factor for placenta accreta spectrum (adjusted odds ratio, 11.80; 95% confidence interval, 7.65-18.19). Moreover, endometrial thickness <7 mm was still an independent risk factor for placenta accreta spectrum (adjusted odds ratio, 3.91; 95% confidence interval, 1.57-9.73) in the matched cohort after PSM. Causal mediation analysis revealed that approximately 63.9% of the total effect of gravidity and 18.6% of the total effect of ovarian stimulation protocol on placenta accreta spectrum were mediated by endometrial thickness. CONCLUSION: The findings of our study indicate that thin endometrial thickness is an independent risk factor for placenta accreta spectrum in women without previous cesarean delivery undergoing assisted reproductive technology treatment. The clinical significance of this risk factor is slightly lower than that of placenta previa. Furthermore, our results demonstrate that endometrial thickness plays a significant mediating role in the relationship between gravidity or ovarian stimulation protocol and placenta accreta spectrum.

Chronic endometritis positively correlates with the aggravation of intrauterine adhesions but has limited effects on reproductive prognosis with antibiotic application.

OBJECTIVE: To assess the effect of chronic endometritis (CE) diagnosed by CD138 staining on the aggravation of intrauterine adhesions (IUAs), and the reproductive prognosis after transcervical resection of adhesions (TCRA). METHODS: Sixty-three patients with severe IUAs (group A) and 119 patients with moderate IUAs (group B) were included in this retrospective study. TCRA and endometrial biopsy with CD138 staining were performed. Participants in each group were classified into two subgroups: CE group and NCE group (without CE). Patients were treated with a course of oral antibiotics for 2 weeks after TCRA. Embryo transfer would be performed if patients had embryos after operations. RESULTS: Increased incidence of CE was found in group A (18/63, 28.57%) compared with group B (18/119, 15.13%) (P = 0.030). No significant differences were found in the comparisons of chemical pregnancy rate, early miscarriage rate, or full-term pregnancy rate between the CE group and NCE group (P > 0.05), in either the subgroup analysis of group A and group B, or the total analysis. CONCLUSION: CE has a positive correlation with the aggravation of IUAs. CE did not have a negative impact on the reproductive prognosis of patients with moderate or severe IUAs after TCRA followed by antibiotic administration.

Correlation between hysteroscopy findings in patients with hydrosalpinx and chronic endometritis.

OBJECTIVE: To evaluate the role of hydrosalpinx in susceptibility to chronic endometritis (CE). METHODS: This is a retrospective cohort study, which includes 624 patients with hydrosalpinx (group A) and 789 patients without hydrosalpinx (group B) undergoing laparoscopy and hysteroscopy simultaneously. Endometrial morphology was recorded under hysteroscopy. Endometrial biopsy was obtained after hysteroscopy, and immunohistochemical staining for syndecan-1 (CD138) was carried out. RESULTS: No significantly statistical differences were found between the two groups when comparing the incidence of endometrial hyperemia or endometrial micro-polyps under hysteroscopy (P > 0.05). Hydrosalpinx had a significant impact on the incidence of CE (P < 0.05) (plasma cell count: no plasma cells: odds ratio [OR] 0.71, 95% confidence interval [CI] 0.58-0.88, P = 0.002; ≥1/high-power field [HPF]: OR 1.40, 95% CI 1.14-1.74, P = 0.002; ≥3/HPF: OR 1.50, 95% CI 1.18-1.91, P = 0.001; ≥5/HPF: OR 1.62, 95% CI 1.27-2.21, P < 0.001). There were no significant differences in the comparison of plasma cell count between the unilateral hydrosalpinx group (274 patients) and the bilateral hydrosalpinx group (350 patients) (P > 0.05). CONCLUSION: The presence of hydrosalpinx increased the incidence of CE. Bilateral hydrosalpinx did not significantly increase the incidence of CE compared with unilateral hydrosalpinx.