Prevalence, Outcome, and Predictors of Placenta Migration among Pregnant Women with Placenta Praevia in Enugu Nigeria

Abstract

Background: Placenta praevia is one of the leading causes of obstetric haemorrhages and a major contributor to maternal and fetal morbidity and mortality. Although low‑lying placentae are common during routine midtrimester anomaly scans, the incidence of placenta praevia at term remains low, probably due to placenta migration. It is important to follow‑up pregnant women with low‑lying placentae to identify the few whose placenta will remain in the lower segment and hence at risk of major obstetric haemorrhage. Aim: The objectives of this study were to determine the prevalence, predictors, and pregnancy outcome of low‑lying placenta diagnosed in the midtrimester. Materials and Methods: The study was a cohort study with longitudinal follow‑up of 416 pregnant women from the University of Nigeria Teaching Hospital, Enugu State University Teaching Hospital, and Mother of Christ Specialist Hospital who had an ultrasound diagnosis of low‑lying placentae between 16 weeks and 20 weeks of gestation. Data analysis was performed using the Statistical Package for the Social Sciences (SPSS) version 22. P < 0.05 was considered statistically significant. Results: The prevalence of low‑lying placenta at 20, 24, 28, 32, and 36 weeks of gestation was 51%, 41.3%, 22.3%, 12.7%, and 10.5%, respectively. 87.3% of those with low‑lying placenta had normally situated placenta at term. Previous caesarean section and male gender were significant predictors of placenta praevia at delivery (P < 0.001 and P = 0.03, respectively). Conclusion: Despite the high prevalence of low‑lying placenta before 20 weeks of gestation, only a few of these placentas remain low‑lying at term. Previous caesarean section and male gender were significant predictors of placenta praevia at delivery. This study recommends a routine ultrasound scan in the second or third trimester for placenta localisation.