Maternal apolipoprotein E genotype as a potential risk factor for poor birth outcomes: The Bogalusa Heart Study

The objective of this study was to assess the association between apolipoprotein E (apoE) genotype and preterm birth (PTB) and small for gestational age (SGA).

ApoE phenotyping was performed on 680 women linked to 1065 births. Allele frequencies were compared and PTB and SGA risk was estimated using log-binomial regression.

The ɛ2 allele was more common in SGA births (P<0.01). SGA risk was increased among ɛ2 carriers compared with genotype ɛ3/ɛ3, though associations were attenuated following adjustment for maternal age, education, race, smoking and prenatal visits. Stronger associations were observed for term SGA (first birth: adjusted relative risk (aRR)=1.78, 95% confidence interval (CI) 1.06 to 2.98; any birth: aRR=1.52, 95% CI 0.96 to 2.40) and among whites specifically (first: aRR=2.88, 95% CI 1.45 to 5.69; any: aRR=2.75, 95% CI 1.46 to 5.22).

Associations between maternal apoE genotype and SGA may represent decreased fetal growth in women with lower circulating cholesterol levels.