Lucy Is 16 Weeks Pregnant and Undergoes Maternal Serum Screening

Multiple Choice

Lucy is 16 weeks pregnant and undergoes maternal serum screening to measure her maternal alpha fetoprotein levels (AFP) . Her AFP level is several times higher than normal levels. For which of the following disorders should Lucy be offered additional testing?

A) trisomy 21, a chromosome abnormality
B) sickle-cell disease, an autosomal recessive disorder
C) spina bifida, a neural-tube defect
D) hemophilia A, a sex-linked recessive disorder
E) Lucy does not need additional testing for any disorder.