Maternal serum alpha-fetoprotein is a marker for fetal anomalies in pediatric surgery

Maternal serum alpha-fetoprotein (MS-AFP) screening has become part of routine obstetric care. Although elevated MS-AFP was originally associated with neural tube defects (NTD), it is also able to detect several fetal anomalies of interest to a pediatric surgeon, ie, ventral abdominal wall defects, intestinal atresias, and sacrococcygeal teratomas. Previously, decreased MS-AFP had only been associated with fetal trisomies, but not surgically correctable lesions. In the present study, we review our recent experience with both elevated and decreased MS-AFP as a marker to detect fetal anomalies of concern to the pediatric surgeon. Forty-one fetal anomalies were associated with 333 pregnancies referred for follow-up after abnormal MS-AFP screening results from November 1985 through November 1986. One hundred ninety-six were elevated and 139 were decreased. In most cases, evaluation included counseling, repeat MS-AFP, level Il ultrasound, and amniocentesis. This revealed elevated MS-AFP to be associated with 32 (16.3%) anomalies (2 NTD, 5 anencephalics, 5 ventral abdominal wall defects, 1 stage IV-S neuroblastoma, 1 renal anomaly, 1 ventriculomegaly, 15 fetal demises, and 2 fetal-maternal bleeds). Decrease in MS-AFP was associated with nine (6.4%) anomalies (2 congenital diaphragmatic hernias, 3 Down's syndrome, 1 Turner's syndrome, 2 duodenal atresias, and 1 choroid plexus cyst). In this study, MS-AFP detected several fetal anomalies known to be associated with abnormal MS-AFP and three anomalies not previously described (congenital diaphragmatic hernia, neuroblastoma, and choroid plexus cyst). Elevated as well as decreased MS-AFP are significant and should be pursued by a full prenatal evaluation. MS-AFP screening and prenatal detection of fetal anomalies will lead to more appropriate management of the newborn by altering the time, mode, or place of delivery.