Research article

Maternal risk factors for abnormal placental growth: The national collaborative perinatal project

Kesha Baptiste-Roberts¹ , Carolyn M Salafia^2,3 , Wanda K Nicholson^4,5 , Anne Duggan⁶ , Nae-Yuh Wang⁷ and Frederick L Brancati⁷

¹  From the Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA

²  From Placental Analytics, LLC, Larchmont, NY, USA

³  From Institute for Basic Research, Staten Island, NY, USA

⁴  From the Department of Obstetrics and Gynecology, Johns Hopkins School of Medicine, Baltimore, MD, USA

⁵  From the Department of Population and Family Health Science, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA

⁶  From the Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, USA

⁷  From the Department of Medicine, Johns Hopkins School of Medicine, Baltimore, MD, USA

author email corresponding author email

BMC Pregnancy and Childbirth 2008, 8:44doi:10.1186/1471-2393-8-44

Published:	23 September 2008

Abstract

Background

Previous studies of maternal risk factors for abnormal placental growth have focused on placental weight and placental ratio as measures of placental growth. We sought to identify maternal risk factors for placental weight and two neglected dimensions of placental growth: placental thickness and chorionic plate area.

Methods

We conducted an analysis of 24,135 mother-placenta pairs enrolled in the National Collaborative Perinatal Project, a prospective cohort study of pregnancy and child health. We defined growth restriction as < 10^th percentile and hypertrophy as > 90^th percentile for three placental growth dimensions: placental weight, placental thickness and chorionic plate area. We constructed parallel multinomial logistic regression analyses to identify (a) predictors of restricted growth (vs. normal) and (b) predictors of hypertrophic growth (vs. normal).

Results

Black race was associated with an increased likelihood of growth restriction for placental weight, thickness and chorionic plate area, but was associated with a reduced likelihood of hypertrophy for these three placental growth dimensions. We observed an increased likelihood of growth restriction for placental weight and chorionic plate area among mothers with hypertensive disease at 24 weeks or beyond. Anemia was associated with a reduced likelihood of growth restriction for placental weight and chorionic plate area. Pre-pregnancy BMI and pregnancy weight gain were associated with a reduced likelihood of growth restriction and an increased likelihood of hypertrophy for all three dimensions of placental growth.

Conclusion

Maternal risk factors are either associated with placental growth restriction or placental hypertrophy not both. Our findings suggest that the placenta may have compensatory responses to certain maternal risk factors suggesting different underlying biological mechanisms.