Sonographic prenatal diagnosis of marginal placental cord insertion: clinical importance.

OBJECTIVE: To assess the impact of a sonographic diagnosis of marginal placental cord insertion on birth weight and duration of pregnancy. METHODS: A retrospective chart review was performed for 100 singleton pregnancies with prospectively identified marginal placental cord insertion. RESULTS: Birth weights below the 10th percentile occurred in 6.25% of pregnancies without preeclampsia. Spontaneous preterm delivery occurred in 7.3% of pregnancies without preeclampsia. Rates of birth weight below the 10th percentile and preterm delivery were not significantly different from those in the general population. Preeclampsia developed in 4 patients; all had elective preterm deliveries, and all gave birth to neonates with birth weights below the 10th percentile. CONCLUSIONS: A prenatal diagnosis of marginal placental cord insertion is not associated with increased risk of growth impairment or preterm delivery.