A fetal doppler ndi cholumikizira chamanja cha ultrasound chomwe chimagwiritsidwa ntchito kuzindikira kugunda kwa mtima kwa fetal kwa chisamaliro choyembekezera. Zimagwiritsa ntchito mphamvu ya Doppler kuti ipereke chithunzithunzi chomveka cha kugunda kwa mtima. Zitsanzo zina zimawonetsanso kugunda kwa mtima pakugunda pamphindi (BPM).

Fetal monitor imatchedwanso kuti mayi ndi mwana, ndi sensa yomwe imagwiritsidwa ntchito kuwunika momwe thupi la amayi ndi makanda limayendera. Imatha kuzindikira kusintha kosiyanasiyana kwa thupi, kukulitsa ndi kulimbikitsa chidziwitsocho, kenako ndikuchisintha kukhala chidziwitso chamagetsi, kenako kuwerengera ndikusintha zambiri. Ngati index yomwe yatchulidwayo yapyola, iyambitsa alamu.