Question: when can fetal heartbeat be detected with doppler

title: Doppler fetal monitor
text: Manufacturer : popular manufacturers are Baby Dopper , Sonoline , Newman Medical , Nicolet ( purchased by Natus ) , Arjo - Huntleigh , and Summit Doppler ( now Cooper Surgical ) . Probe type : waterproof or not . Waterproof probes are used for water births . Probe frequency : 2 - MHz or 3 - MHz probes . Most practitioners can find the heart rate with either probe . A 3 - MHz probe is recommended to detect a heart rate in early pregnancy ( 8 -- 10 weeks gestation ) . A 2 - MHz probe is recommended for pregnant women who are overweight . The newer EchoHeart 5 - MHz transvaginal probes aids in the detection of fetal heart tones ( FHT ) early in pregnancy ( 6 -- 8 weeks ) and for patients who have a retroverted uterus or throughout pregnancy for FHT detection for women who are obese . Heart rate display : some Dopplers automatically display the heart rate on a built - in LCD ; for others the fetal heart rate must be counted and timed by the practitioner .