A prospective cohort study to assess the association between early pregnancy bleeding and risk of poor pregnancy outcome

Abstract

Introduction 16-25% of the pregnancies are complicated by threatened miscarriage. The knowledge on outcomes of the pregnancy following a threatened miscarriage is important to the obstetrician in surveillance, decision making and planning further management of the pregnancy. Therefore the need of data on the adverse maternal and perinatal outcomes following a threaten miscarriage is well evident in local context. Objectives To assess the association between early pregnancy bleeding and risk of poor maternal and perinatal outcomes. Methods A prospective cohort study was carried out in the Obstetrics and Gynaecology Unit, Teaching Hospital Peradeniya for a period of ten months. All pregnant women with a history of notable vaginal bleeding in the first 24 weeks of gestation were recruited as subjects and age and parity matched, pregnant women without a history of any vaginal bleeding, were recruited as controls. Multiple pregnancies or foetus with congenital anomalies, women with known bleeding disorders and congenital uterine abnormalities were excluded. Sample size was 440 including 220 in each group. Several selected maternal and perinatal events were considered as outcome variables. Small for gestational age was detected via locally adapted customized growth charts. Data were analysed by using SPSS 23.0. Ethical clearance was obtained by Ethics Review Committee Faculty of Medicine, Peradeniya. Results The mean maternal ages were 27.8 and 28.2 years respectively in study and control groups. Mean age and body mass index were comparable in the two groups. Threatened miscarriage was significantly associated with an increased relative risk for small for gestational age (P Conclusions and Recommendations Threatened miscarriage carries a significant risk of adverse maternal and perinatal outcomes and it is identified as a risk factor for small for gestational age, low birth weight, foetal growth restriction, preeclampsia and preterm labour. Placental abruption is associated with threatened miscarriage with an increased relative risk, though the association was not significant. This knowledge should be applied by the clinicians to counsel the pregnant women with threatened miscarriage and at the same time be alert on symptoms and signs of those adverse effects in order to plan the future management. Probability of inclusion of early prediction of adverse maternal and perinatal events by threatened miscarriage in to obstetric management guidelines should be determined. In future studies it is recommended to evaluate association between each adverse outcome and threatened miscarriage independently and to evaluate the outcomes following bleeding in the first and second trimesters separately.