How Soon After Having Sex Can I Know If I Am Pregnant?

In order to know how soon you can detect a pregnancy, it’s important to understand your menstrual cycle – when you ovulate and when you get your period.

Ovulation is when the ovary releases an egg and pregnancy happens when that egg is fertilized by a sperm after intercourse. A woman is most likely to get pregnant if she has sex in the three days before and up to the day of ovulation.

Each woman’s cycle length can be a little different, with the time between ovulation and when the next period starts ranging anywhere from one week more than 2 weeks. (Source:

Credit: American Pregnancy Association

Laboratory-quality pregnancy tests like the ones provided free of charge at the Fort Worth Pregnancy Center may be able to tell if you are pregnant – as soon as 10 days after you’ve ovulated.* (Source: National Library of Medicine)

How do pregnancy tests work?

Pregnancy tests work by detecting one of the key early signs of pregnancy: a hormone called human chorionic gonadotrophin (hCG). This hormone is only made when a woman is pregnant. (Source:

When is the best time to take a pregnancy test?

The best time to take a pregnancy test starts the day that you miss your period, making it likely that the hCG has built up to a level that can be detected by the test. The best time to test is first thing in the morning, as the levels of hCG will have built up overnight.

How accurate are the tests?

The lab-quality tests provided at the Fort Worth Pregnancy Center are 99% accurate within 10 days of conception. However, not all women have regular cycles or know when they ovulated. So, while a positive result is likely to be accurate, a negative result may be misleading. Some women have a negative result and test again a week later to find that it is positive because their hCG levels were too low to be picked up at the time of the first test.

What if my tests are negative but I still haven’t gotten my period?

There are a variety of causes for a missed period besides pregnancy. If you continue to get negative results and still no period, you should consult your doctor.

What should I do if I think I might be pregnant?

If you think you might be pregnant, give yourself the peace of mind of confirming with a lab-quality test at your doctor’s office, or visit a pregnancy center that offers testing free of charge. Also, remember that seeing a positive result on a pregnancy test does not always mean that you are (or will stay) pregnant. According to the National Library of Medicine, up to 25% of pregnancies end in miscarriage, most in the first trimester. There is also a 1-2% chance of an ectopic (tubal) pregnancy, which poses a serious health risk if not identified and removed. A no-charge ultrasound at the Fort Worth Pregnancy Center will confirm the pregnancy and assess for heartbeat, location in the uterus and how far along you are.

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