By Anne Harding

NEW YORK (Reuters Health) - Women who are having unprotected sex are more likely to suspect they might be pregnant, and to follow-up on this suspicion if a home pregnancy test is handy, a new study in the American Journal of Preventive Medicine shows.

Very early pregnancy is a key time in fetal development, but many women may not recognize they are pregnant at this stage and may continue with unhealthy habits such as smoking or drinking, lead researcher Dr. Mary D. Nettleman told Reuters Health. Finding a way to alert women to the possibility of early pregnancy is thus crucial to both fetal and maternal health, she added.

Public health efforts focus on helping women keep themselves and their fetus healthy after they recognize they are pregnant, and there is increasing attention being paid to "preconception" health, Nettleman of Michigan State University in East Lansing, noted. However, she said, "no one focuses on the time between conception and when a women recognizes her pregnancy. It just wasn't thought to be a modifiable variable."

To investigate whether having pregnancy tests on hand might help, she and her colleagues randomly assigned 198 women to receive a home pregnancy test kit in the mail, including three test strips and instructions on how to order more, or to a control group that didn't receive pregnancy tests.

All study participants got letters informing them about the importance of early pregnancy recognition, instructions on home pregnancy test use and a brochure on preconception health, contraceptive use and pregnancy planning.

None of the women were trying to get pregnant, but none of them were using birth control. Over a 6-month period, the women who had received the tests suspected they were pregnant 2.3 times, on average, while the control group suspected pregnancy an average of 1.2 times. The women given the tests used them in 93 percent of the instances when they thought they might be pregnant, but women in the control group used them just 64 percent of the time.

While the study was conducted among low-income women who were either on Medicaid, had a child on Medicaid, or who had received assistance from Medicaid during their last pregnancy, Nettleman said she believes the findings apply to all women who are not trying to get pregnant but also not trying to prevent pregnancy, no matter what their socioeconomic status.

These women are at greatest risk of delayed recognition of pregnancy, the researcher noted. "A woman who doesn't want to get pregnant, it's probably easier for her to ignore her symptoms, it's just not on her radar screen if you will," she said.

But once a woman recognizes she's pregnant, she will likely take steps to adopt a healthier lifestyle, Nettleman added. "It's a very powerful behavioral stimulus. I just want to create that stimulus as early as possible." Every woman of childbearing age should keep a pregnancy test on hand, she advised, just in case.

SOURCE: American Journal of Preventive Medicine, February 2009.

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