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"Tweaking" the Test

Pregnancy Tests

When trying to conceive the dreaded "two week wait" can feel like an eternity. That's the span of time between when conception likely occurred and the first day of the (hopefully) missed period. Many women may take home pregnancy tests early, only to be disappointed by a negative result. Now though, some are trying to make those negatives positive - using photo enhancing software.

"Tweaking," as it is called in internet forums, involves taking a picture of a seemingly negative test and then adjusting the contrast of brightness in the hopes of uncovering a second line. While the method is getting a lot of attention on social media, medical professionals are skeptical. "It is possible that digital manipulation of photos of home pregnancy tests may pick up some early positive tests. However, we don't know the validity and reliability of this approach," says Erin Clark, MD, an OB-GYN with University of Utah Health. "In other words, the rate of false positive and false negative results hasn't been reported. We simply do not know if this is an accurate approach to testing."

Home pregnancy tests work by detecting the pregnancy hormone hCG in the urine according to Clark. "The hCG rises over time, making detection of pregnancy easier the farther a woman gets from her missed period," she says. "Very early pregnancies (before the missed period) have very low levels of hCG that typically cannot be detected by home pregnancy tests."

Clark warns that those low levels of hCG may not indicate a viable pregnancy. "There is a risk of detecting a chemical pregnancy," she says. "That is, in fact, a very early miscarriage in which there may be detection of low levels of hCG in urine or blood that but never development of a visible pregnancy by ultrasound."

"Earlier pregnancy detection with 'tweaking' isn't generally medically necessary, and while the intent is to decrease anxiety, I worry that the opposite may be true," Clark says. "False positive and false negative test results can have psychological and emotional consequences. Sometimes false positive or negative results are more harmful than the stress of waiting a few more days for a more accurate test result."