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How is it that a woman can get pregnant on birth control?

1 doctor weighed in
Dr. Nikolaos Zacharias
Obstetrics & Gynecology - Maternal Fetal Medicine

In brief: <95% effectiveness.

Birth control pills are only theoretically 99% effective; as their absorption varies and that the vast majority of women forget a dose here and there, the actual efficacy is probably <95%, therefore you should anticipate at least a 5% chance of getting pregnant while on the pills.
Iuds are a safer and promptly reversible option that costs less money and is perfect for mutually monogamous couples.

In brief: <95% effectiveness.

Birth control pills are only theoretically 99% effective; as their absorption varies and that the vast majority of women forget a dose here and there, the actual efficacy is probably <95%, therefore you should anticipate at least a 5% chance of getting pregnant while on the pills.
Iuds are a safer and promptly reversible option that costs less money and is perfect for mutually monogamous couples.
Dr. Nikolaos Zacharias
Dr. Nikolaos Zacharias
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