First trimester sonographic characteristics of patients with recurrent spontaneous abortion.

First trimester ultrasonographic evidence of FHM infers a good prognosis for normal pregnancies, although similar data in RSA is scarce. Abortion before 20 weeks' gestation occurred in 12 of 167 control patients (7.2%) and five of 23 patients with RSA (21.7%) after detection of fetal heart motion (P = 0.0382). The abortion rate decreased with a MSS-CRL difference of > 8 mm in controls but not in patients with RSA. We conclude that the probability of pregnancy success is not improved with FHM identification in patients with RSA.