When Did I Conceive? Calculate Your Due Date.

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You can get just about any information online. However, if you are wondering, “When did I conceive?” or “How far along am I?” A due date or conception calculator can give you a good estimation, but it won’t give you the information you need to make decisions about your pregnancy. 

It’s also important for you to know if you are really pregnant. Home pregnancy tests, while far more accurate than they used to be, are a verification of pregnancy, not a confirmation.

The only way to be sure is to get an ultrasound. An ultrasound measures how far along you are, your approximate conception date, the due date, and the viability of your pregnancy. Ultrasound exams provide images and include various measurements of your developing baby that can help estimate how far along you are in weeks and the approximate conception date. 

The Pregnancy Help Center can provide a cost-free ultrasound to those who qualify after a positive pregnancy test is performed.

How To Know When You Conceived

There are a few ways to have a general idea of your conception date before an ultrasound.

1. Ovulation

The first way to find out your conception date is to determine when you were last ovulating. In general, women can only conceive when ovulating — that is, their ovaries release a new egg into their fallopian tubes for fertilization. That means you can use your ovulation dates to determine when you became pregnant.

Ovulation usually occurs about two weeks after your menstrual period and lasts for two or three days. This means you can sometimes determine when you conceived based on your ovulation cycles — simply determine when your last menstrual period was and add approximately two weeks.

However, this method isn’t always accurate. Not all women have the same cycles of menstruation and ovulation. Some women’s menstrual cycles are irregular, some range between 21-35 days, others have ovulation periods closer to or further from their menstrual period, and some women aren’t sure when their last period was. In other words, calculating conception based only on your body cycles can be difficult.

2. Intercourse

Another way to learn your conception date is to try to determine the last time you had sexual intercourse. Unfortunately, this method isn’t accurate either. Conception is a process that takes time, and a man’s sperm can stay alive inside your body for up to a week after sex.

This can make it difficult to determine when you conceived, especially if you had more than one partner when you ovulated. Also, remember that you could become pregnant even if you or your partner used birth control, since no method of birth control is 100% effective at preventing pregnancy.

3. Ultrasound

An ultrasound is the most foolproof way to determine your conception date. A pregnancy confirmation ultrasound can help you determine the approximate time you conceived and the age of your growing baby.

The Pregnancy Help Center can provide a cost-free ultrasound so you can confirm your pregnancy. This method of determining your conception date can be more accurate than a date-based calculation, especially for women with irregular periods or women who don’t know their last menstrual period date.

Start with a free pregnancy test appointment at the center and get the answers you need on abortion pills, procedures, pregnancy, adoption, parenting, and more. 

References:

Professional, C. C. M. (n.d.). Conception. Cleveland Clinic. https://my.clevelandclinic.org/health/articles/11585-conception

American Pregnancy Association. (2022, February 11). Ultrasound: Sonogram. https://americanpregnancy.org/prenatal-testing/ultrasound/

Menstrual cycle: What’s normal, what’s not. (2023, April 22). Mayo Clinic. https://www.mayoclinic.org/healthy-lifestyle/womens-health/in-depth/menstrual-cycle/art-20047186