At approximately 5 and a half weeks your baby’s heart started beating and by 8 weeks the four chambers of the heart have formed. Initially the fetus is deep within the pelvic region and the pelvic bones are in the way of hearing the heartbeat through a Doppler. Between 6 and 14 weeks your caregiver will first check for the heartbeat. There are several factors involved in detecting the heartbeat:
- The type of instrument used
- Pinard Horn – low tech and low intervention as the Pinard Horn doesn’t project sound waves, however it usually cannot detect the fetal heartbeat until around 18-20 weeks
- Fetoscope – a combination of Stethoscope and Pinard Horn the Fetoscope stays low intervention but by upping the tech through adding the stethoscope it allows a well skilled individual to detect a heartbeat as early as 12 weeks.
- Doppler – uses ultrasound, the bouncing of sound waves, to listen to the heartbeat. A high power Doppler can detect the heartbeat as early as 8 weeks however most Dopplers detect the heartbeat around 12 weeks.
- Ultrasound (Sonogram) there are two types internal and external, both involve bouncing high-frequency sound waves off the fetus which in turn creates an image on the computer screen.
- Internal – is rarely done for the heartbeat alone as it is very invasive to the mother and the fetus‘ space, however it is able to detect the heartbeat the earliest at just after 6 weeks.
- External – using a clear jelly and a probe on mom’s abdomen you can see and hear the baby’s heartbeat at around 8 weeks.
- Fetal position
- Error in date of conception
- Your build
- Your uterus
Don’t despair if you don’t hear it the first time, setup your next appointment and bring the dad along to hear it next time.