Elevated maternal serum hCG in the second trimester increases prematurity rate and need for neonatal intensive care in primiparous preeclamptic pregnancies.

OBJECTIVE

This study was designed to investigate the association between the serum concentrations of maternal second trimester human chorionic gonadotropin (hCG) and the severity of preeclampsia.

METHODS

At Kuopio University Hospital, a total of 487 preeclamptic primiparas had undergone maternal serum screening for Down's syndrome between January 1993 and December 1998. Of these, 37 women had unexplained elevated serum hCG concentrations [> 2.5 multiples of the median (MoM)], whereas the remaining 450 preeclamptic women had normal hCG results. Pregnancy characteristics and outcome measures in these groups were evaluated using logistic regression.

RESULTS

Elevated midtrimester hCG concentrations were associated with higher rates of low-birth-weight infants, preterm delivery, and need for neonatal intensive care. The adjusted odds ratios was 2.11 [95% confidence interval (CI): 1.03-4.32], 2.08 (95% CI: 1.10-4.30), and 2.27 (95% CI: 1.14-4.51), respectively.

CONCLUSIONS

In primiparous preeclamptic pregnancies, an elevated maternal serum hCG concentration is a marker of early-onset and severe disease with significant maternal and perinatal morbidity. This finding, in turn, reinforces the association between elevated hCG concentrations and placental damage in early pregnancy. Elevated maternal serum hCG levels identify a subgroup of preeclamptic patients who deserve more intensive observation.