Effects of taking birth control during pregnancy
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Birth Control Use During Pregnancy: Safety and Fetal Effects
Birth Control Pills and Fetal Development
Current research indicates that taking birth control pills during early pregnancy—often before a woman realizes she is pregnant—does not cause abortion or miscarriage, nor does it appear to have significant harmful effects on fetal development. Birth control pills work by preventing ovulation and thickening cervical mucus, but once pregnancy occurs, these mechanisms do not impact the developing embryo or fetus 17. Most evidence suggests that accidental use of oral contraceptives in early pregnancy is unlikely to harm the fetus or cause birth defects 17.
Risk of Miscarriage, Preterm Birth, and Low Birth Weight
A systematic review and meta-analysis found that women who used oral contraceptives before becoming pregnant had a slightly higher risk of preterm birth, but a lower risk of spontaneous abortion (miscarriage). There was no significant difference in the risk of low birth weight between women who had used oral contraceptives and those who had not . This suggests that while there may be a small increase in the risk of preterm birth, the overall risks to the pregnancy are minimal.
Birth Control Pills and Abortion
Oral contraceptives do not cause abortion. They are designed to prevent pregnancy, not to terminate an existing one. If a woman continues taking birth control pills after conception, the pills do not affect the implanted embryo or cause miscarriage .
Hormonal Effects and Maternal Health
Birth control pills contain synthetic hormones (estrogen and progestin) that can cause side effects in women, such as nausea, headaches, mood changes, and irregular bleeding 238. Some studies have found a slight increase in the risk of depression among women using hormonal contraceptives, especially those with higher estrogen content or longer duration of use 510. However, these effects are primarily on the mother and not directly on the fetus.
Recommendations and Counseling
Healthcare professionals generally advise women to stop taking birth control pills once pregnancy is confirmed, but accidental use in early pregnancy is not considered a reason for alarm or for terminating the pregnancy 17. Women who become pregnant while using birth control should consult their healthcare provider for reassurance and guidance.
Conclusion
Accidental use of birth control pills during early pregnancy is common and, according to current evidence, does not cause abortion or significant harm to the fetus. There may be a slight increase in the risk of preterm birth, but no increased risk of miscarriage or low birth weight. The main side effects of birth control pills are experienced by the mother, not the developing baby. Women who discover they are pregnant while taking birth control should stop the pills and consult their healthcare provider, but there is no need for undue concern about fetal harm based on current research 167.
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