In vitro fertilization and embryo transfer is an independent risk factor of the placenta accreta spectrum in the termination of pregnancy during the mid-trimester：a retrospective cohort study on perinatal management

Abstract

Abstract BACKGROUND The most common aetiology of placenta accreta spectrum (PAS) is a defect in the endometrial-myometrial interface. The incidence and characteristics of the PAS among women with termination of pregnancy after the second trimester are unknown. This study aimed to determine the effect of in vitro fertilization and embryo transfer (IVF-ET) on patients with termination of pregnancy during the mid-trimester and the risk factors of placenta accreta spectrum among this population. METHOD This was a retrospective observational study of women who underwent induced abortion or termination of pregnancy in the second trimester from January 2013 to October 2023 in the Sixth Affiliated Hospital of Sun Yat-sen University. A total of 230 patients were age-matched and divided into a spontaneous conception group and an in vitro fertilization and embryo transfer group to compare the difference in incidence of placenta accreta spectrum and their outcomes during follow-up. The primary outcome was the morbidity of the placenta accreta spectrum. RESULTS Our results indicated that women with IVF-ET had a significantly higher risk of suffering PAS (29.6% vs. 13.0%, P = 0.002) as well as morbid placenta accreta spectrum (13.9% vs.5.2%, P = 0.039) during abortion. The amount of postpartum bleeding [200(100.0-520.0) ml vs. 140.0(80.0-240.0)ml, P = 0.004], the rate of postpartum haemorrhage (24.3% vs.11.3%, P = 0.010), and the time of retained products of conception > 4 weeks (40.4%vs.24.8%, P = 0.030) were significantly higher in the IVF-ET group than in the spontaneous conception group. IVF-ET (odds ratio = 2.42, P = 0.027), a hysteroscopy history(odds ratio = 2.67, P = 0.028), and cryopreserved embryo transfer (odds ratio = 4.26, P < 0.001) were independent risk factors for PAS during abortion. CONCLUSION Patients with IVF-ET, especially cryopreserved embryo transfer, had a significantly high risk of PAS and postpartum haemorrhage during the abortion of mid-trimester, suggesting that these patients need more attention to avoid severe complications and preserve fertility during labour.