INCIDENCE OF FETAL LOSS IN INFERTILITY PATIENTS AFTER DETECTION OF FETAL HEART ACTIVITY WITH EARLY TRANSVAGINAL ULTRASOUND

A study was conducted to determine the incidence of fetal loss after f etal heart activity (FH) had been detected with vaginal ultrasound. On e hundred sixty patients with serum beta-human chorionic gonadotropin greater than 25 mIU/mL were studied. Patients underwent serial vaginal ultrasound evaluations every one to two weeks beginning the 5th week from the last menstrual period (LMP), through 12 weeks. One hundred fo urteen (71%) patients had confirmation of FH (mean days from LMP, 48.1 +/- 2.9 SD). Of these, 106 (93%) patients had normally progressing pr egnancy, while 8 (7%) experienced a fetal loss in the first trimester. There were no significant differences in fetal wastage after unstimul ated cycles (n = 30), clomiphene citrate cycles (n = 24), human menopa usal gonadotropin (hMG) cycles (n = 2 7) and gonadotropin releasing ho rmone agonist/hMG cycles (n = 33). Although mean gestational age at wh ich post-FH fetal loss was diagnosed was 67.2 +/- 7.2 days, only two o f the losses occurred after 65 days (1.7%). The probability of a pregn ancy loss after the detection of FH is approximately 7%, and fewer tha n 2% of pregnancies with previously documented FH may have a fetal los s after nine weeks.