Intrauterine growth restriction and placental location.

OBJECTIVE

The purpose of this study was to determine whether an association exists between intrauterine growth restriction (IUGR) and second-trimester placental location.

METHODS

A case-control study was performed in well-dated singleton pregnancies with (n = 67) and without (n = 205) IUGR (defined as estimated fetal weight <10th percentile for gestational age at the last sonographic examination) to investigate the association between IUGR and placental location. Placental location was determined by sonography at 16 to 20 weeks' gestation. Maternal, perinatal, and delivery characteristics were abstracted from medical records. Group comparisons were made by the Student t test, chi(2) analysis, the Fisher exact test, the Wilcoxon test, and analysis of variance. Multivariable logistic regression analysis was used to determine the relationship between IUGR and placental location.

RESULTS

In both groups, the most common placental locations in the second trimester were anterior and posterior. After adjusting for potential confounders (including race, chronic hypertension, and hypertensive disorders of pregnancy), IUGR pregnancies were nearly 4-fold more likely to have lateral placentation (odds ratio, 3.8; 95% confidence interval, 1.3-11.2) compared with anterior or posterior placentation.

CONCLUSIONS

Pregnancies complicated by IUGR are significantly more likely than non-IUGR pregnancies to have lateral placentation in the second trimester.