Am I pregnant? When you are trying to get pregnant, you probably want to know the answer as soon as possible. If you might accidentally be pregnant, you definitely want to know the answer as soon as possible. When can you take a pregnancy test and expect a reliable positive or negative result? Testing too soon may simply result in wasting a test, but waiting to test until after you expect your period can be difficult – especially if your periods are not regular.
Most home pregnancy test kits will tell you that you will get the most accurate result if you wait to test until after your period is due. However, it is possible to test sooner and receive a reliable, positive result. I received positive results on three pregnancy tests at 9 days post ovulation, 10 days post ovulation, and 11 days post ovulation with each of my pregnancies. I got these positive results well before the first day of my expected period. Many women will not be able to test that early, and here is why.
Each woman has a different timeline for menstrual cycle, although the basic process in a healthy woman is fairly predictable. Each menstrual cycle is composed of two parts. During the first half of the cycle the lining of the uterus thickens in preparation for a possible pregnancy. At the same time, an egg matures in the ovaries. At roughly 14 days after the menstrual cycle begins, the ovaries release the egg in a process called ovulation. While 14 days is the general timeline given for ovulation, a woman’s cycle may be shorter or longer, and she may ovulate before that 14 day mark or after it. For instance, I typically ovulate on day 9 of my cycle, which is why I could test so early. The egg then travels through the fallopian tube to the uterus.
The menstrual cycle now enters what is called the “luteal phase.” At this point in a woman’s cycle, the egg is either fertilized (conception) or it is not. If the egg is not fertilized, the hormone levels drop, and the uterus is shed. If the egg is fertilized, it will take roughly 6-12 days after ovulation to be implanted in the uterus. In some cases, though not in all, implantation bleeding results. Be careful not to confuse implantation bleeding with an early period.
Once the fertilized egg implants in the uterus, the developing embryo begins sending a hormonal signal to the pregnant woman telling her body not to have a period. The placenta secretes human chorionic gonadotropin, or hCG. Pregnancy tests measure the levels of hCG in a woman’s body. In a non-pregnant female there is no hCG, but measurable levels of hCG indicate pregnancy. The amount of hCG in a woman’s body during a healthy pregnancy will increase rapidly. The average levels of hCG in early pregnancy are 14 mIU/ml at 7 days post ovulation, compared to 21 mIU/ml at 14 days post ovulation. Very sensitive “early pregnancy tests” will test low levels of the hormone, sometimes as low as 15-25 mIU/ml.
So when can you take a pregnancy test and get a reliable, accurate result? Testing too early, before the embryo begins secreting the hormone, will result in a disappointing negative result and a wasted pregnancy test.
If you pay close attention to your cycle and know when you ovulated, you can take a sensitive home pregnancy test such as First Response Early Result Pregnancy Test 9 or 10 days after you ovulated and expect a relatively accurate result (or roughly 23 or 24 days into your average cycle). If you have shorter cycles, you can test earlier.
For example, when trying to conceive our second child, my cycles were approximately 20 days long, so very short. I ovulated on day 7 or 8, and the days just before ovulation were my most fertile days (i.e. the best days to try to conceive). Knowing that I ovulated on day 7 or 8, I began testing on day 17 of my cycle, before my expected period and roughly 10 days after ovulation. I accurately received a positive test result on my trusted First Response Early Result Pregnancy Test 3 days before I expected my period.
However, if you get a negative result during this time period, you may still be pregnant. The test you used may not have been sensitive enough to read the low levels of the pregnancy hormone in your urine, you may have ovulated later than you expected, or the embryo may have implanted later than expected (i.e. at 12 days post ovulation rather than at 8-10 days post ovulation).
If you get a negative result on an early pregnancy test, you can always wait until the first day of your missed period to retest. Or, if you are like most women, you can simply continue to test each day until you get your positive result or your period. However, knowing when you can take a pregnancy test and expect a reliable result can save you disappointment, anxiety, and money.
Sources:
Early-Pregnancy-Tests.com. “Pregnancy Calendar Guide: Week-by-Week,” last accessed July 21, 2009.
Luteal Phase, Implantation, and When to Test for Pregnancy,” last accessed July 21, 2009.
Fertilinet.com. “HCG Levels in Early Pregnancy,” last accessed July 22, 2009.
WomensHealth.gov, “Menstruation and the Menstrual Cycle,” last accessed July 21, 2009.
