Pregnancy dating and viability
So your baby may be on the 30th percentile or the 80th percentile, but still be normal.Unfortunately, if you’re around 8 weeks of pregnancy, and your dating is accurate, a lack of heartbeat usually indicates a miscarriage.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.If you’ve experienced any vaginal bleeding or spotting, or have significant pain, an ultrasound might be performed to check on the viability and location of your pregnancy (e.g. Like many procedures and medications during pregnancy, large scale double-blind studies to prove the safety or risk of ultrasound are nearly impossible.Early ultrasounds might be used routinely, or only when there are concerns.If you haven’t had any signs of a miscarriage and are less than 8 weeks pregnant, it’s possible that you’ve simply had a scan too early.
This type of dating is based on averages, as many women ovulate about 14 days after the start of their last period, and expect a new period 14 days after ovulation.
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.