ABSTRACT
Neural tube defects are reported one of the important congenital malformation in the world, with an incidence of 1.4 to 2 per 1000 pregnancies. Maternal serum AFP at the second trimester is used as screening test. But this is associated with numerous causes, including twins, fetal death, misdated pregnancies, cystic hygromas, teratomas, renal abnormalities, esophageal atresia and aberrations in the placenta. If the AFP level was elevated, targeted ultrasonography should be evaluated for confirming the gestational age and fetal viability, fetal number. Then if the ultrasonographic examination is nondiagnostic, or if an NTD is suspected, amniotic fluid AFP should be measured with acetylcholinesterase. But the false positive rate of the AF-AFP is high, and there is 0.3% of the false positive rate in amniotic acetylcholinesterase. This time the women with normal ultrasonographic examination continue the pregnancy after counseling of family history, past history with follow up of ultrasonography. We report a case with elevated second trimester MS-AFP, AF-AFP and positive amniotic acetylcholinesterase, but in which repeated sonographic findings were normal and result in delivery of a healthy baby without anomalies.