OBJECTIVE: The purpose of this study was to evaluate prospectively midtrimester homocysteine concentration levels for the prediction of superimposed preeclampsia in women with chronic hypertension.

STUDY DESIGN: Between March 1, 2000, and February 1, 2002, pregnancies that were complicated by chronic hypertension that required medication had homocysteine, vitamin B₁₂, and folate concentrations measured between 16 and 20 weeks of gestation. All women received folate supplementation. An upper limit threshold for increased homocysteine was defined as the mean value plus 2 SDs.

RESULTS: Fifty-seven women were enrolled. Mean homocysteine concentration levels were 5.1±1.7 μmo/L for the 16 women who had preeclampsia compared with 4.7±1.3 μmo/L for the 41 women without preeclampsia (P=.56). Two of 16 women with preeclampsia (13%) had concentration levels that exceeded the 95th percentile (6.9 μmo/L) compared with 2 of 41 women (5%) without preeclampsia (P=.31). The sensitivity and specificity were 13% (95% CI, 1.6-38.3) and 95.1% (95% CI, 83.5-99.4), respectively.

CONCLUSION: Second-trimester homocysteine concentration levels were not helpful in the prediction of preeclampsia in chronically hypertensive women.