OP01.03: Accuracy of sonographic features in diagnosing Caesarean scar pregnancy during the early first trimester

Abstract

Objectives:To investigate what are the risk factors for early pregnancy loss (EPL) after in vitro fertilisation-embryo transfer (IVF-ET). Methods: This was a retrospective study in a single reproductive centre. The infertile patients included in this study underwent IVF treatment between June 2016 to December 2017. During this period, 13,977 women were identified with a singleton pregnancy by TVS at day 27-29 after IVF-ET. The gestational sac diameter (GSD), embryonic length (EL), embryonic heart rate (EHR) and YSD and the presence of intrauterine hematoma (IUH) were measured. The clinical characteristics were also collected. The first trimester pregnancy outcome of these women was noted at 12 weeks of gestation. A backward Wald logistic regression model was established to screen the risk factors. Results: 1,926 cases of spontaneous miscarriage ≤ 12 weeks of gestation, which were assigned as EPL and 12,051 women with an ongoing pregnancy for > 12 weeks of gestation. When compared with the ongoing pregnancy group, the MA, infertility duration and transfer cycle were significantly higher, and the day-14 human chorionic gonadotrophin and the endometrium (EM) thickness on transfer day were significantly lower in the EPL group (p < 0.001).Based on the TVS measurements, the GSD (18.5±3.6 vs. 13.2 ± 4.8 mm), EL (3.5 ± 0.9 vs. 1.2 ± 1.6 mm), YSD (3.6 ± 0.4 vs. 2.6 ± 1.5 mm) and EHR (114.5 ± 12.2 vs. 42.4 ± 53.5 bpm) were significantly greater in the ongoing pregnancy group than those in the EPL group (p < 0.001). The incidence of IUH (16.0% vs. 18.8%, P = 0.002) was also markedly higher in the EPL group. MA, GSD, EL, YSD, EHR and EM on transfer day finally entered the logistic model after stepwise screening. The probability of EPL was: exp(z)/(1 + exp(z)), where z = 2.432 + (0.092 × MA) -(0.074 × EM) -(0.114 ×GSD) -(0.245 × EL) -(0.034 × HR) -(0.159 × YSD). Conclusions: The maternal age, gestational sac diameter, embryonic length, yolk sac diameter, heart rate of day 27-29 and endometrium thickness on transfer day were risk factors.