When Did I Conceive?

So, you’re pregnant. But on what date did you conceive, and how can you know who the father is? 

Although pinpointing the exact moment of conception isn't scientifically precise, there are natural rhythms and cycles, similar to your menstrual period, that can help you estimate when you likely conceived.

What Date Did I Conceive?

Whether you're 2 or 20 weeks pregnant, a bit of simple math can help you estimate when you conceived.

Typically, ovulation—the time when you can get pregnant—occurs over a two-to-three-day period each menstrual cycle, about two weeks after your last period began.

Conception Date Calculator

By calculating the time since your last period, you can get a rough idea of your ovulation window and, hence, when you conceived.

If that math is a bit challenging to do in your head, there are free online calculators that can help, or you can text us at (843) 892-6193.

Again, this is just a rough approximation. It’s important to remember that each woman’s menstrual cycle and ovulation window are different. Some ovulate for longer periods of time than others, and some have theirs earlier or later during their menstrual cycle.

Additionally, sex before ovulation can still lead to pregnancy because sperm can survive for up to five days. This means that sperm from pre-ovulation intercourse can fertilize an egg if it lasts long enough.

Conception Calculator

Conception Date from Ultrasound

Another way to determine the conception date is through an ultrasound. Because fetuses grow at a predictable rate, their age can be accurately measured, making an ultrasound more reliable than an ovulation calculator.

Having an ultrasound not only helps you know when you conceived but can also confirm the viability of the fetus.

You can have an ultrasound performed at your local OBGYN office; however, there’s usually paperwork and billing involved. Alternatively, your local pregnancy center may be able to offer free ultrasound services without the need for hospitals or insurance companies to get involved.

Get Help Determining Your Conception Date

If you need help figuring out which day you conceived or if you have any questions about pregnancy in general, we’re here to help.

Simply send a text to (843) 892-6193 and get a real certified nurse to answer your questions and walk you through your options.