You’ve just entered the “two-week wait”, and the hours are passing like days. If you are like most trying-to-conceive women, you won’t want to wait a second longer than necessary to see if this is the month you will get the BFP (big fat positive). Unlike the generations of women that came before us, women today no longer have to wait for a missed period before taking a home pregnancy test, but knowing exactly when to take a pregnancy test to ensure accurate results is not as simple as it might seem.
About home pregnancy tests
To determine when to take a pregnancy test, it is important to know a bit about how home pregnancy tests work. Home pregnancy tests work by detecting the presence of the hormone called “human chorionic gonadotropin” (hCG) in urine. HCG is a hormone secreted by the embryo once it has implanted into the wall of the uterus, which typically occurs 6-8 days after conception (or 7-10 days post ovulation).
How quickly after conception a pregnancy test can detect a pregnancy is a function of its sensitivity to hCG, which is measured in thousandths of International Units and notated by the abbreviation mIU. Because the levels of hCG found in a pregnant woman’s urine start out very small and increase rapidly as the embryo grows, the more sensitive the test is to hCG, the quicker the test will be able to accurately test for pregnancy. A newly pregnant woman will have around 25 mIU of hCG at 10 days past ovulation, 50 mIU at 12 days past ovulation and 100 mIU at around two weeks past ovulation.
The “earliest” pregnancy tests available are calibrated to detect hCG at the 20 mlU/ml level. These tests can provide an accurate result as early as seven to 10 days after ovulation, well before you have missed your period.
When it is time to take a pregnancy test, you will notice that they come in two types: test strip or midstream format. Choosing between these different types is simply a matter of personal preference. Some women find the midstream format tests to be more convenient because they do not require collecting urine in a cup. However, these tests are more expensive than the test strip format.
Early signs of pregnancy
As you are deciding when to take a pregnancy test, it might also be helpful to take note of any of the physical signs and symptoms that may suggest conception has occurred. Some very early signs of pregnancy include:
- Implantation bleeding: some women experience some spotting and/or cramping as the embryo implants into the wall of the uterus
- Tender or swollen breasts
- Food cravings/aversions
- If you experience any or all of these symptoms in the first 7 to 10 days post ovulation, it might well be worth it to take a pregnancy test sooner rather than later.
Of course, if you’re still not sure when to take a pregnancy test, for example, in instances of extreme cycle irregularity, it’s always a good idea to consult your ObGyn.
More Pregnancy Test Articles
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- Pregnancy Midstream Tests
- Pregnancy Test Review and Comparison Chart
- How Early Can I Test for Pregnancy?
- How Accurate Are Pregnancy Tests?
- What’s a Faint Line on a Pregnancy Test Mean?
- What are Pregnancy Test Evaporation Lines?
- What is a Chemical Pregnancy?
- Missed your Period? The Role of HCG in Pregnancy & Testing
- First Morning Urine & Pregnancy Testing
- Pregnancy Test Kit Sensitivity & Accuracy
- FAQ: How do pregnancy tests work?
- FAQ: I missed my period but my pregnancy test is negative
- FAQ: Can I receive a false positive result on my pregnancy test? Or a false negative?
- The History of the Pregnancy Test
- Negative Pregnancy Test and Missed Period
- Implantation Bleeding
- When to Take a Pregnancy Test
- Best Pregnancy Test
- Pregnancy Test Accuracy
- Faint Line on Pregnancy Test
- Blood Pregnancy Test
- False Positive Pregnancy Test
- Pregnancy Test False Negative
- How Early Can You Take a Pregnancy Test?
- Home Pregnancy Test
- Ovulation Test as Pregnancy Test