It's a major moment in a woman's life: Those minutes when she sits in the bathroom with a test stick, waiting to find out if she's pregnant. There are so many questions swirling through her head, and there's one home pregnancy test provides more information than the rest, estimating how far along she is in her pregnancy.
The Clearblue Advanced Pregnancy Test with Weeks Estimator—which launched in Europe in 2008 and debuted in the U.S. in 2013—not only tells you if you are or aren't pregnant, but uses modern technology to also estimate whether you are 1-2 weeks pregnant, 2-3 weeks, or 3+ weeks into the pregnancy.
The test has two strips instead of one, and screens for the human chorionic gonadotropin (hCG) hormone that appears in a woman's urine stream after fertilization. Clearblue says the test is 99 percent accurate at detecting pregnancy from the day of a woman's expected period, and about 93 percent accurate in estimating the number of weeks she's been pregnant. The company tested 5,000 urine samples from 2,000 women in its clinical trials to determine that hCG levels are a reliable way to estimate the days since last ovulation.
Obstetricians say the new test may be particularly helpful for women with irregular periods, but there's some disagreement about the accuracy of using hCG to date pregnancy. The doctors also stress that a pregnancy test is no substitute for ultrasound, the best way to determine just how far along a woman is.