E. Jauniaux et al., THE ORIGIN OF ALPHA-FETOPROTEIN IN FIRST-TRIMESTER ANEMBRYONIC PREGNANCIES, American journal of obstetrics and gynecology, 173(6), 1995, pp. 1749-1753
OBJECTIVE: Our purpose was to evaluate the origin of alpha-fetoprotein
in the maternal circulation and coelomic fluid of pregnancies with an
empty gestational sac on first-trimester ultrasonographic examination
. STUDY DESIGN: The alpha-fetoprotein level and the affinity of alpha-
fetoprotein for concanavalin A Sepharose was measured between 8 and 11
weeks of gestation in the maternal serum and coelomic fluid of nine p
regnancies complicated by an empty gestational sac and of 27 normal pr
egnancies. RESULTS: The maternal serum alpha-fetoprotein level in pati
ents with an empty gestational sac was high in seven cases and normal
in two cases. In these cases the median level was significantly (p < 0
.01) higher in the serum and lower in the coelomic fluid compared with
normal pregnancies. In eight cases of the nine pregnancies with an em
pty sac, > 50% of alpha-fetoprotein molecules in the coelomic fluid we
re of the concanavalin A nonreactive fraction, whereas in one case the
coelomic fluid sample contained <5% of this fraction. A similar distr
ibution was found in the corresponding serum samples. CONCLUSION: Norm
al or high maternal serum AFP levels and alpha-fetoprotein molecules p
redominantly of yolk sac origin in the coelomic fluid of pregnancies w
ith an empty gestational sac on ultrasonography provide further eviden
ce that the most likely explanation for this feature is the early deat
h of the embryo with persistence of the placental tissue.