3/2/2009

We'll presume the context of this question is one in which a woman becomes pregnant while taking birth control pills, and continues taking birth control for some period of time before the pregancy is discovered.

While birth control pills are a very reliable form of birth control, they are not 100% effective and there is always a chance of a woman using birth control pills becoming pregnant. Thousands of women have become pregnant while taking birth control pills and it can be assumed that a large number of these women experienced an overlap in time between when they became pregnant and stopped taking birth control pills. And the vast majority have had healthy babies.

All birth control pill products are accomanied instructions warning to stop taking them if the woman becomes pregnant. But there is little published evidence indicating that fetuses exposed to birth control pills during early stages of pregancy are at an increased risk of complications or birth defects.

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