How to Calculate Conception Date

How to Calculate Conception Date

When you find out that you’re pregnant, naturally the first thing you want to know is your due date! That is completely normal, since that is the exciting day that you will get to meet your little one! However, your next question might be what day you conceived. It sounds pretty simple right? Your conception date will be the day you had sex, right? Not so fast… Claim Your 20 Free Pregnancy Tests – Click Here

Remember that sperm can live in the body for up to five days, so the day you had sex is not necessarily the date you conceived. Let’s explain how to figure out the date you conceived.

Figuring out your date of conception

If you have already been to the doctor, and know your expected due date, figuring out your date of conception is quick and easy! All you need to do is start with your due date, and count back 266 days. Simple as that! If that sounds like too much work to you, there are also a ton of online conception/due date calculators that will do all the work for you. So, if you know your due date already, it is a snap to figure out your date of conception.

However, if you have not seen a doctor yet, and are trying to figure out your date of conception, it might be a little bit harder to figure out. If you have already been charting your cycles for ovulation purposes, figuring out your date of conception might be a bit easier. If you know when you ovulate, you know that your egg must be fertilized within 24 hours of ovulation, so that can narrow it down quite a bit for you.

Do the math!

However, this is how to determine an estimated date of conception if you haven’t been tracking your cycles. First of all, determine the date that you started your last period, and mark it down, if you haven’t already. That is Cycle Day #1. Then add eleven days to the date your last period started. This is the first day that it was possible for you to conceive. Now, add another ten days to the first day that conception was possible. Those ten days are the days that it is possible for you to have conceived.

Again, that is not to say at all that you have 10 days in which you can get pregnant every month. Far from it. You are only fertile for about 2-5 days during an entire cycle. But since for this exercise, you do not know exactly when you ovulate, we will have to allow some wiggle room to do your math. You will have to narrow it down within those ten days to determine what your actual date of conception was.

Remember: conception dates are just estimates

Keep in mind, that just like due dates, conception dates are usually just estimates. You can sometimes pinpoint the exact date that you conceived, but not always. At least knowing your estimated date of conception will give you a better idea of when you conceived.

As always, keep in mind that even if you do know your date of conception and your due date, it is no guarantee of when your baby will arrive. Babies come whenever they decide it’s time! Sometimes late, sometimes early – but only 3% come exactly on their due date!

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Lindsey Zaldivar
Lindsey Zaldivar | ConceiveEasy
Lindsey lives in Roselle, Illinois with her husband and son Harry. In between keeping up with a busy toddler, she enjoys blogging about parenting, cooking, crafting at The Accidental Wallflower.