Best Pregnancy Tests

Home pregnancy tests: Sensitivity, reliability and readability.

The clear winner of the multiple scientific studies and reviews of home pregnancy tests (HPTs) is the First Response Early Result Pregnancy Test (*Est. $13 for two-test kit). The manufacturer, Church & Dwight Co., reports it to have a sensitivity of 25 mIU/ml.  A study published in Clinical Chemistry in 2001 confirmed that First Response is sensitive to both regular human chorionic gonadotropin (hCG) and hyperglycosylated hCG (H-hCG) at 25 mIU/ml. Hyperglycosylated hCG is a form of hCG that the authors found comprised more than half of the hCG in a woman's urine during the first weeks of pregnancy and while similar to hCG, most HPTs tested did not have the same sensitivity to H-hCG as they did to regular hCG.

Another study published in 2004 in the American Journal of Obstetrics and Gynecology found that First Response consistently detected 12.5 mIU/ml of hCG. At this level of sensitivity First Response could detect 95 percent of the pregnancies in the study on the first day of the woman's missed period.

A later study published in 2005 in the Journal of the American Pharmacist Association redid the sensitivity testing of various home pregnancy tests using a mixture of hCG and H-hCG to better mimic the natural mixture of various hCG forms that occur during the first weeks of pregnancy. First Response detected the hCG mixture at 6.3 mIU/ml, the lowest concentration they concocted. In addition test readers had the highest confidence when reading positive and negative results with the First Response, though no digital HPTs were included in the testing. Testing done by a major consumer group in 2003 found a similar sensitivity to hCG, at 6.5 mIU/ml, making First Response Early Result Pregnancy Test the most sensitive out of the 18 HPTs tested. In addition, it was one of the easiest tests to read at lower concentrations of hCG.

Parents.com and About.com both choose First Response Early Result as one of their top choices because of how early it can be used. We found a few consumers posting at Viewpoints.com, Epinions.com and Drugstore.com, however, who say that First Response Early Result didn't work because they tested negative before or at the time of their missed period, then tested positive a few days later. Even though First Response is marketed as "the only test that tells you six days before your missed period," this claim is based on the fact that with the test's high sensitivity, it could tell you you're pregnant as early as six days before your missed period. However, since every woman's cycle is unique results may vary. In addition, in 10 percent of pregnant women, implantation hasn't occurred yet at the time of a missed period so no pregnancy test would be positive. (For more on false negatives and false positives see "How Pregnancy Tests Work.")

The runner-up to First Response Early Result is Clearblue Easy +/- Pregnancy Test ($10.50 for two-test kit). Like First Response, Clearblue Easy detects both hCG and H-hCG in concentrations as low as 25 mIU/ml according to the 2001 Clinical Chemistry study. An American Journal of Obstetrics and Gynecology study found that Clearblue Easy was able to detect hCG as low as 12.5 mIU/ml on four out of six tests. In a test of sensitivity with a mixture of hCG and H-hCG, Clearblue Easy was able to detect 25 mIU/ml, according to the results published in the Journal of American Pharmacists Association. The authors calculated that given the average hCG concentrations in pregnant women, detecting 25 mIU/ml of the hCG mixture would allow Clearblue Easy to detect 80 percent of pregnancies on the first day of a missed period. A major consumer reporting group finds Clearblue Easy to be one of the easier HPTs to interpret at low concentrations, but at Viewpoints.com and Epinions.com some users complain that the results can be difficult to interpret. Consumers at Drugstore.com also note false positives, and while these can have various causes, PeeOnAStick.com reports that evaporation lines can occur, giving the appearance of a positive result, if the test is read after its recommended reading time.

While First Response Early Result and Clearblue Easy +/- Pregnancy Test are the clear favorites, it is important to mention home pregnancy tests that fared poorly in the scientific studies. A 2004 American Journal of Obstetrics and Gynecology study found design flaws in Confirm Pregnancy Test (*Est. $12 for two-test kit) and Clear Choice Pregnancy Test (*Est. $5 for one test). Both reported pregnancies when no urine had been placed on the tests and had incidences when the control lines did not appear. The 2005 study from the Journal of the American Pharmacists Association also kept track of how many of the devices were faulty in each brand of home pregnancy tests researchers tested. The e.p.t. +/- Home Pregnancy Test ($11.50 for two-test kit) was the clear loser in this category with 8 percent of the more than 60 devices tested not working properly.

Digital readouts are easier than trying to read a faint pink line

Since many women want to know as soon as possible whether they're pregnant, tests with increased sensitivity have been developed and have flooded the market in recent years. Still, it doesn't matter how sensitive a test is if you have trouble deciphering the results. All tests should have a control line to indicate the test is working properly. Most use a second line, either in a separate window or in a plus-sign shape, to indicate a positive result. But according to reviews and to those who've used pregnancy tests, deciding whether or not you see that second line can be open to some interpretation, and if you wait more than 10 minutes to read the result, a urine evaporation line could look like a positive pregnancy indicator line. Digital home pregnancy tests attempt to make reading between the lines easier, letting women know their results with words instead of hard-to-interpret lines.

The best-reviewed digital home pregnancy test is First Response Gold Digital Pregnancy Test (*Est. $16 for two-test kit). The digital display reads yes or no and the company claims that it "uses a proprietary gold technology that is so sensitive it actually detects two different forms of hCG" with a sensitivity of 18 mIU/ml. Scientific studies have shown that many home pregnancy tests on the market can detect multiple forms of hCG, though with varying sensitivity, and they do not all have this proprietary technology. First Response Gold Digital can be taken up to four days before a missed period, but the accuracy is only 58 percent. Due to the limits of human biology, the only way to get higher accuracy from a home pregnancy test is to wait longer.

The Clearblue Easy Digital Pregnancy Test (*Est. $18 for three-test kit) comes in a close second to the First Response Gold Digital, with a sensitivity of 25 mIU/ml to hCG. Practically speaking, the Clearblue digital pregnancy test works like any other test -- you place the absorbent strip in your urine stream for five seconds and a flashing hourglass symbol appears to let you know the test is working properly. Within three minutes, the test does the interpretation for you, displaying the words pregnant or not pregnant in a small window. The test results remain on display in the window for up to 24 hours -- at which time the device shuts off. A 2008 study published in Current Medical Research and Opinion demonstrated that the Clearblue Easy Digital Pregnancy Test was able to detect 100 percent of the samples with 25 mIU/ml of hCG and that all of the test readers were confident in reading the results. However this study only tested the Clearblue Easy Digital Pregnancy Test against nondigital pregnancy tests and the study was funded entirely by Swiss Precision Diagnostics, the manufacturer of Clearblue Easy, and all of the study's authors were company employees. Also, while the label says the test can be taken up to four days before a missed period, the promised accuracy is only 53 percent as not all women are producing hCG then.

We did find some complaints about the Clearblue Easy Digital Pregnancy Test. Some women get a test malfunction reading, which is an image of a book, and we read reports of incorrect assembly or a dead battery -- in which cases the test cannot be used. Altogether, reviews say there's little advantage to digital pregnancy tests, and readout errors can make interpreting their results almost as frustrating as regular tests. In addition, digital tests are more expensive than nondigital pregnancy tests and don't offer improved accuracy.