MATERNAL SERUM ALPHA-FETOPROTEIN LEVELS IN PREGNANCIES AMONG BLACK AND WHITE WOMEN WITH FETAL OPEN SPINA-BIFIDA - A UNITED-STATES COLLABORATIVE STUDY

In the present study second-trimester maternal serum α-fetoprotein levels were analyzed from 146 pregnancies assciated with fetal open spina bifida to identify whether affected pregnancies from the black population were associated with higher matermal serum α-fetoprotein levels than their white counterparts. Pregnancies in black women not affected by open spina bifida are already known to have higher maternal serum α-fetoprotein levels. All of the cases were analyzed with gestational ages assigned by last menstrual period, and all maternal serum α-fetoprotein values were expressed as multiples of the median, to correct for differences in gestational age and assay among the 15 centers reporting data. The levels from affected pregnancies in white and black women fit log Gaussian distributions, with medians of 3.10 and 4.37 multiples of the median, respectively, on the basis of singleton, unaffected, white pregnancy medians. These results support adjustment of maternal serum α-fetoprotein values for race in black women; in addition, if a screening program's pollcy is to screen at a comparable risk in the two races, a higher maternal serum α-fetoprotein multiple of the median cutoff would be justified for black women. © 1990.