Prior Preterm Birth and Birthweight Below the 5 th Percentile are Independent Risk Factors for Recurrence of a Small for Gestational Age Neonate

Objective::This study aimed to determine:(1)whether recurrent deliveries of a small for gestational age(SGA)neonate are associated with increased obstetrical or neonatal complications;(2)whether the risk factors that can predict small for gestational age(SGA)recurrence.Methods::This study was based on Soroka Medical Center's Obstetrics electronic database.The database consisted of 109022 women who had 320932 deliveries between the year 1988-2014.The study cohort included 6.8%(7368/109022)of these patients who gave birth to a singleton SGA neonate on their first delivery and had more than one delivery.The study population was divided into two groups according to the outcome of the subsequent delivery:(1)women with sporadic SGA who delivered a non-SGA neonate(n=5416);(2)women with recurrent SGA(n=1952).SGA defined as birthweight<10 th percentile.Maternal and neonatal complications were compared between the two groups.Logistic regression was used to determine independent risk factors for SGA recurrence.Results::The prevalence of birthweight<5 th percentile was higher among the recurrent SGA group in the first delivery(P<0.001).Bedouin ethnicity was more prevalent in the recurrent SGA group(P<0.001).The rate of preterm delivery was higher in the first delivery of the recurrent SGA group(P=0.015).The sporadic SGA group had a higher rate of perinatal mortality during the first pregnancy(P=0.017).The rate of severe hypertension(P=0.005),polyhydramnios,meconium-stained amniotic fluid,nonreassuring fetal heart rate and total perinatal mortality(P<0.001)were higher in the second delivery of the recurrent SGA group.In a logistic regression model,preterm delivery and birthweight<5 th percentile at the first delivery was found to be independent risk factors for recurrence of an SGA neonate in the subsequent birth(relative risks:1.530,confidence interval:1.249-1.875;relative risks:1.826,confidence interval:1.641-2.030,respectively).Conclusion::Women with recurrent SGA neonates have specific clinical characteristics.Among women who deliver an SGA neonate,preterm delivery,and birthweight<5 th percentile are independent predictors for its recurrence.