How Can I Calculate My Date Of Conception. An ultrasound, however, determines the estimated gestational age of an embryo or fetus by taking biometric measurements. However, this is how to determine an estimated date of conception if you haven’t been tracking your cycles.
You can help the process along by keeping a basal body temperature chart. Estimating conception date can also be more difficult. Hence it is calculated by subtracting 266 days from your estimated due date.
It uses just simple maths.
Show you on an ob wheel you are due 38 weeks from your conception date if you were having 28 day cycles. You can purchase low cost, high quality pregnancy tests here. A missed menstruation cycle is one of the earliest signs of pregnancy. However, this is how to determine an estimated date of conception if you haven’t been tracking your cycles.