Clinical significance of unexplained elevated maternal serum alpha feto-protein in second trimester of pregnancy
Keywords:Maternal serum alpha-fetoprotein, Maternal and fetal outcome, Pregnancy
Background: Alpha-fetoprotein (AFP) is the major serum protein in the embryonic stage and in the early fetal stage. The aim of this study was to measure maternal serum AFP levels in second trimester between 15-20 weeks of gestation and to determine whether unexplained elevated MSAFP levels is an effective predictor of adverse pregnancy outcome among Indian population.
Methods: This study was a prospective observational study, carried out on 400 pregnant women. Maternal serum alpha-fetoprotein (MSAFP) was measured between 15 and 20 weeks of gestation after excluding congenital malformation or birth defects. MSAFP level was determined by using a radio-immunoassay technique. Women with MSAFP level >2.0 MoM was considered as abnormal while MSAFP level≤ 2.0 MoM was considered as normal. All women were followed up till delivery and pregnancy outcomes were noted and compared between two groups.
Results: Women with elevated MSAFP had significantly higher adverse pregnancy outcomes (75.4%) compared to women with MSAFP ≤2.0 MoM (26.1%) (p<0.0001 with relative risk of 2.89, 95% confidence interval 2.276 -3.667).
Conclusions: Unexplained elevated MSAFP has high sensitivity, specificity, positive predictive value and negative predictive value in predicting adverse pregnancy outcomes. It would, therefore be worthwhile screening pregnant women in second trimester for maternal serum alpha-fetoprotein levels as it would help to identify high risk pregnancies and allow close antenatal survillence for better pregnancy outcome.
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