BackgroundEarly pregnancy loss (EPL) is the most prevalent complication, particularly in couples undergoing assisted reproductive technology treatment. The present study aimed to determine whether the serum β-human chorionic gonadotropin (β-hCG) level after 14 days of embryo transfer, either alone or in conjunction with other parameters in IVF/ICSI cycles, could be used to predict subsequent EPL.MethodsThis was a retrospective cohort study of all couples who received clinical pregnancy and underwent fresh IVF/ICSI cycles at a single large reproductive medical center between January 2013 and June 2020. The research involved a total of 6600 cycles. For risk variables, we conducted the least absolute shrinkage and selection operator (LASSO) analysis, and for risk scoring, we used logistic regression coefficients. To analyze relevant risk factors for EPL, univariate and multivariate logistic regression analyses were employed. Areas under the curve (AUC) were determined and compared between β-hCG and other factors using receiver operating characteristic (ROC) curves.Resultsβ-hCG level was considerably lower in women who had EPL than in those who were ongoing pregnancy (564.03 ± 838.16 vs 1139.04 ± 1048.72 IU/L, p< 0.001). Univariable and multivariable logistic regression revealed that β-hCG levels were significantly correlated with the probability of EPL, independent of other risk factors. More importantly, the β-hCG level could independently predict the occurrence of EPL and was comparable to the model that combined other risk factors. The optimal serum β-hCG cut-off value for predicting EPL was 542.45 IU/L.ConclusionsOur results suggest that the serum β-hCG level has a strong independent predictive value for EPL occurrence in fresh IVF/ICSI cycles.

Background This study aims to study whether the change of endometrial thickness between the day of human chorionic gonadotrophin (HCG) administration and the day of embryo transfer (ET) has any effect on ectopic pregnancy (EP) rate following fresh in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycles. Methods This study retrospectively analyzed 3134 patients who underwent fresh IVF/ICSI ET, including 3022 intrauterine, 112 ectopic cycles. Multiple logistic regression analysis and stratified analysis were used to study the effect of endometrial compaction after HCG administration on EP in patients with non-thin endometrium after adjusting for confounding factors. Results After adjusting for confounders, multiple logistic regression analysis found that the risk of EP in the compaction group was significantly lower than that in the non-compaction group (OR = 0.49; 95% CI: 0.31–0.78; P = 0.0023). The results of the stratified analysis demonstrated the EP rate in patients with an endometrial thickness ≥ 8 mm on the day of ET; the compaction group significantly reduced the incidence of EP (OR = 0.49; 95% CI: 0.31–0.79; P = 0.0036). In patients with an endometrial thickness ≥ 8 mm on the day of ET, the incidence of EP had no statistical significance in two group (OR = 1.02; 95% CI: 0.18–5.88; P = 9790). Conclusion(s) In patients with non-thin endometrium, endometrial thickness compaction from the day of HCG to the ET day reduced the risk of EP significantly.