Maternal serum alpha-fetoprotein levels in anembryonic pregnancy

Maternal serum alpha-fetoprotein (AFP) levels were determined in 21 women with threatened miscarriage in whom an ultrasound diagnosis of anembryonic pregnancy was confirmed. Fourteen of the 21 patients had normal AFP levels; the remaining seven had levels above the 95th centile of the reference range. This is in contrast to earlier findings of an association between low levels of AFP in anembryonic pregnancy. It is concluded that most anembryonic pregnancies are pregnancies in which the fetus has been lost rather than pregnancies in which the fetus was never present.