ABSTRACT
BACKGROUND/AIMS: To evaluate maternal serum transformed alpha-fetoprotein (MSt-AFP) levels, a new molecular conformation of AFP was used in cases of threatened preterm labor (TPL). METHODS: Prospective case-control study. Maternal serum levels of classical AFP and transformed AFP (t-AFP) were compared between 2 groups matched by gestational age: 25 women with TPL and 25 healthy pregnant women as controls. RESULTS: There was no significant difference in classical maternal serum AFP (MSAFP) levels between the 2 groups. In contrast, MSt-AFP levels were significantly lower in cases of TPL than in the control group [7.64 (1.78-29.06) vs. 33.38 (13.80-190.50) ng/ml; p = 0.006]. Similarly, the t-AFP:AFP ratio was also decreased in the TPL group [0.04 (0.004-0.12) vs. 0.16 (0.05-0.80); p = 0.008]. There was no significant correlation between MSAFP and MSt-AFP levels. CONCLUSIONS: MSt-AFP levels are decreased in women with TPL.
Subject(s)
Obstetric Labor, Premature/blood , alpha-Fetoproteins/metabolism , Adult , Case-Control Studies , Female , Humans , Pregnancy , Prospective Studies , Protein Conformation , Statistics, NonparametricABSTRACT
AIM: To evaluate transformed alpha-fetoprotein (t-AFP) (a new molecular conformation of alpha-fetoprotein) levels in maternal serum and fetal serum in normal pregnancy. METHODS: Prospective longitudinal study. Fifty pregnant women were studied in two groups: 25 were evaluated in each trimester of pregnancy and near term (12, 20, 32 and 36 weeks) and the other 25 were evaluated at the time of planned cesarean section at term. In the first group, maternal serum t-AFP was measured and in the second group, maternal and fetal serum t-AFP were analyzed. RESULTS: Maternal serum t-AFP levels (medians) were 14.73 ng/mL in the first trimester, 28.29 ng/mL in the second trimester, 30.45 ng/mL in the early third trimester and 8.06 ng/mL in late pregnancy. t-AFP levels were significantly higher in maternal than in fetal serum (P < 0.001). There were no significant correlations between AFP and t-AFP levels in maternal versus fetal serum. CONCLUSIONS: t-AFP increases during pregnancy until the early third trimester and then falls before delivery. t-AFP levels are higher in maternal than in fetal serum which suggests that native AFP is transformed to t-AFP either in the mother or in the placenta.
