Pregnancy week by week

Taking birth control pills during early pregnancy doesn't appear to increase the risk of birth defects.

Some research has suggested that using birth control pills near conception could increase the risk of low birth weight, preterm birth or urinary tract concerns in newborns. But in general, health care providers haven't seen those problems occur.

Birth control pills lower the risk of pregnancy. They also reduce the risk of a fertilized egg implanting outside the uterus (ectopic pregnancy). Ectopic pregnancies most often form in one of the tubes that carry eggs from the ovaries to the uterus (fallopian tubes). If you do conceive while taking a progestin-only birth control pill, sometime called the minipill, there is a slightly higher chance that the pregnancy will be ectopic.

As a precaution, if you suspect you're pregnant, take a home pregnancy test. If that test is positive, stop taking the pill. If taking a home pregnancy test isn't possible, stop taking birth control pills until you can see a health care provider to find out if you're pregnant. In the meantime, use another method of birth control, such as condoms.

If you're worried because you took birth control pills before you knew you were pregnant, talk to your health care provider. But know that there is little risk of birth defects.

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