A transvaginal ultrasound (an internal ultrasound) can detect a heartbeat around 6 weeks of pregnancy.
However, it isn’t uncommon to be unable to detect a heartbeat via ultrasound until closer to 7 or 8 weeks.
Find out more about week 6 of pregnancy in our informative pregnancy week by week series. A mother’s size, the position of her uterus, the location of baby, and the accuracy of dating can all affect when a heartbeat is seen on an ultrasound.
Even with all the variables, it’s very likely you will see a heartbeat by 7 weeks and extremely likely by 8 weeks of pregnancy.
Ultrasounds use sound waves to produce a picture on a screen.
While this is a noninvasive procedure, these waves can cause tissue to heat up.
While many mothers are able to see the heartbeat around 6 weeks, some maternity care providers prefer to wait until 7.5 weeks or more.
By waiting until 7-8 weeks, it is less likely that a dating error could lead to not detecting the heartbeat in a healthy pregnancy.
For many women, this means you’re 4 weeks at about the time of your missed period, and 6 weeks pregnant about two weeks after your missed period.Unfortunately, if you’re around 8 weeks of pregnancy, and your dating is accurate, a lack of heartbeat usually indicates a miscarriage.Having an early ultrasound often depends on your maternity care provider, your personal medical history, and how your current pregnancy seems to be progressing.If there’s concern about when you actually conceived (e.g.you’re still breastfeeding and haven’t had a regular cycle, or you were on birth control) a provider might want an early ultrasound in order to date your pregnancy.It’s important to know that pregnancy dating can be off by up to two weeks.