Abstract
Objective: To examine the associations between a history of recurrent miscarriage (RM) and adverse obstetric and perinatal outcomes in the subsequent pregnancy.
Design: Retrospective cohort study.
Setting: A large tertiary maternity hospital in Shanghai, China.
Population: There were a total of 118,375 deliveries booked for antenatal care and delivery between January 2014 and August 2021 in the database.
Methods: Obstetric and perinatal outcomes were compared among 1,994 women (1.83%) with a history of two or more miscarriages (RM), 11,477 women (10.55%) with a history of one miscarriage, and 95,321 women (87.62%) with no history of miscarriage, respectively. Logistic regression analyses were performed, adjusting for potential confounders.
Main Outcome Measures: Obstetric complications included gestational diabetes mellitus, preeclampsia (sub-classified as preterm and term preeclampsia), placenta previa, placenta accrete, foetal distress, and preterm pre-labour rupture of membranes (PPROM). Perinatal outcomes included mal-presentations, emergency caesarean section, induction, post-partum haemorrhage, preterm birth, stillbirth, Apgar score <7, neonatal asphyxia, neonatal sex, and congenital malformation.
Results: There was an increased risk of adverse obstetric and perinatal outcomes in a subsequent pregnancy for women with a history of RM, including placental dysfunction disorders [preterm preeclampsia (odds ratio [OR]=1.60; 95% confidence interval [CI]: 1.03-2.50), PPROM (OR=1.39; 95% CI: 1.10-1.75), preterm birth (OR=1.40; 95% CI: 1.19-1.64)], and abnormal placentation (placenta previa [OR=1.79; 95% CI: 1.38-2.34], and placenta accrete [OR=4.25; 95% CI: 2.84-6.37]), after adjusting for relevant confounders.
Conclusions: Significant associations existed between RM and adverse obstetric and perinatal outcomes like placental dysfunction disorders and abnormal placentation. Women with a history of one miscarriage were at little increased risk for an adverse outcome in a subsequent pregnancy. Careful surveillance is required in pregnancies following RM, for early detection of possible complications, especially placenta associated diseases.
Funding: National Key Research and Development Program of China (2018YFC1002800), Shanghai Jiao Tong University Trans-med Awards Research (Major Project) (20210201), National Natural Science Foundation of China (81401274 and 82171669) and the Shanghai Science and Technology Commission (17411972700).
Keywords: recurrent miscarriage, obstetric, perinatal outcomes.