Ultrasonic Doppler inspection of the fetal heart

Studies in Diagnostic Ultrasound

“…Robinson (113) has detected foetal heart action with his combined A, B and TMtechnique 45 (days after Ithe beginning of menstruation and has achieved diagnostic certainty beginning in the 8th week. The results bath of the present work and of Robinson (113,114) show that foetal heart activity can be deteoted transabdominally at a oonsiderably earlier stage and with greater reliabillity than has eanlier been considered possible (6,12,70,80,81,85,110). The good results, in bath cases, are lbased on the use of a combined technique; the important factor is the use of B-soanning to looalize the foetus precisely, which in turn ma'kes it easier to direct bhe sound beam accurately to the foetal heart.…”

“…The repolrt met with a favourable response, and during the past 10 years reports of numerous examinations, made using mainly the transabdominal method but also the vaginal Doppler technique, have been published. In many examinations it has been possible to detect Eoetal heart aation through the abdominal wall in the 9th or 10th weeks of pregnancy, but this method has not proved to be reliable until the 12th week or even later (9,12,13,17,18,51,66,70,85,101,110,112,128,130). It has been noted that the vaginal Doppler teahnique lis reliable in the earlier stages of pregnancy.…”

Detection of Fetal Heart Movement in First Trimester of Pregnancy using Pulsed Ultrasound

“…On the other hand, the use of those instruments which use the ultrasonic Doppler principle can provide an immediate answer to the question of fetal life by detecting fetal heart movement. This technique is now a well established procedure (Johnson et al, 1965;Bernstine and Callagan, 1966;Bishop, 1966;Pystynen et al, 1968;Barton, 1968;Brown et al, 1968;Kuah and Embrey, 1968;Muller and Osler, 1969;Resch et al, 1971) but when an abdominal transducer is used it is unreliable before the 12th week of pregnancy. By using a vaginal transducer, however, Jouppila (1971) was able to detect fetal heart action by the Doppler technique at the eighth week of pregnancy, and reported 100% accuracy from the 10th week.…”

Detection of Fetal Heart Activity During Early Pregnancy by Combined B‐Scan and Doppler Examination: A New Application

“…Ultrasonic examination based on the Doppler effect has now been used for nearly a decade for detection of fetal heart activity. It has proved to be a reliable method for detecting heart activity through the abdominal wall from the 12th week of pregnancy onwards (1,2,5). By vaginal Doppler technique fetal heart activity has been observed at 8 weeks, and 100% certainty has been achieved in examinations at 10 weeks of pregnancy (3).…”