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You are pretty sure you know when you ovulated this month and timed the baby making sex perfectly. Now you’ve got all your fingers and toes crossed that this time will be successful and you get to see that elusive positive pregnancy test.
Yes, you’ve heard from all the sources that it is always best to wait until you’ve actually missed your period to take a pregnancy test, but you also know that most of the tests on the market say you can test before that point and you NEED to know right now!
Many women start testing way too early in their eagerness to know. Doing that can line you up for disappointment and false negative results. You will have to spend more money and endure more stress when you have to test again.
Understanding hCG Levels and Pregnancy Test Results
It is important to remember that it takes time for your fertilized egg to become implanted in your uterine wall. The time frame varies from woman to woman, but research shows that 85% of pregnancies start producing hCG between 8 and 10 days after ovulation. The pregnancy hormone (hCG) level will start out very low after implantation and will double every 2 to 3 days.
Let’s say your fertilized egg implanted at 8 days past ovulation (dpo). If you have a normal 28 day cycle, that will be 6 days before your period is due. Maybe by the end of the day, your hCG level is at 5 mIU.
If you wait two days (4 days before your period), your hCG level should be around 10 mIU. Depending on the sensitivity of the pregnancy test you are using, you might be able to get a very light positive result at this point. It’s not likely, but it is possible.
If you were able to wait two more days (2 days before your period), your hCG levels would be around 20 mIU. Your chances of getting a distinct positive result is much better at this point. Most of the pregnancy tests available today are able to detect at around 20 – 25 mIU of hCG.
Not every woman will get results this early. If you happen to have a slow moving fertilized egg that doesn’t implant until 10 DPO, you will not get a positive result until closer to when your period is due.
Also, the doubling rate of the hCG is a variable. The hCG typically doubles every 2 to 3 days. If your hCG is doubling more slowly, a positive result will not show up until later.
So, When Should I Take A Pregnancy Test?
Unless you are a glutton for punishment and have a large disposable income, waiting until 2 or 3 days before your period is due or 11 or 12 days past ovulation to take a pregnancy test would be a good option. But know, a negative result at that point does not mean you are not pregnant. It could be that you are still testing too early based on when your baby implanted and how fast the hCG is doubling.
If you can hold out and wait until AFTER your period was supposed to start, you will get the most reliable results at this point.
Blood Based Pregnancy Tests
If you just can’t wait, you might be able to get quicker results by visiting your doctor for a hCG blood test. Blood tests will measure the hCG in your blood so it bypasses the possibility that your urine is not as concentrated as it needs to be to produce a positive pregnancy test result. That morning coffee and other liquids may contribute to false negative results very early on in your pregnancy.
Depending on the lab, a positive result will be between 5 mIU and 25 mIU of hCG in the blood sample. If the result is at the lower end of a positive result, you will likely have to go back and get another blood test just to make sure the amount is going up.
The accuracy of the serum pregnancy tests is variable depending on the lab your doctor uses and what level of hCG is considered a positive result.