For decades, doctors have warned pregnant women to avoid statin medications (drugs that lower cholesterol) because of worries about birth defects. A new large study from Norway looked at over 800,000 pregnancies and found that babies born to mothers who took statins during early pregnancy had similar rates of birth defects compared to babies whose mothers didn’t take these drugs. When researchers combined this study with previous research, they found no strong evidence that statins cause birth defects. This doesn’t mean all pregnant women should take statins, but it suggests the risk may be lower than doctors previously believed.

The Quick Take

  • What they studied: Whether taking statin medications (cholesterol-lowering drugs) during the first three months of pregnancy increases the risk of birth defects in babies.
  • Who participated: Over 803,000 pregnant women in Norway between 2005 and 2018. The study compared three groups: women who never took statins, women who stopped taking them before pregnancy, and women who continued taking them during early pregnancy.
  • Key finding: About 6.7% of babies born to mothers taking statins had birth defects, compared to 4.3% of babies whose mothers didn’t take statins. However, this small difference could have happened by chance, and when researchers accounted for other health factors, the difference was no longer statistically significant.
  • What it means for you: If you’re pregnant or planning to become pregnant and take statins for heart health, this research suggests the risk to your baby may be lower than previously thought. However, always discuss your specific situation with your doctor before making any changes to your medications, as the decision depends on your individual health needs.

The Research Details

This study used information from Norwegian health records covering all pregnancies from 2005 to 2018. Researchers identified which women filled prescriptions for statins during their first trimester (first three months of pregnancy) and then tracked whether their babies had birth defects. They compared three groups: women who never took statins, women who stopped before getting pregnant, and women who continued taking them during early pregnancy.

The researchers used statistical methods to account for other factors that might affect birth defect risk, such as the mother’s age, smoking, folate use, and other medications. They also combined their findings with results from previous studies to get a better overall picture of the safety of these drugs in pregnancy.

This research approach is important because it uses real-world medical records from an entire country rather than relying on smaller studies or laboratory experiments. By comparing women who stopped statins to those who continued taking them, researchers could better understand whether the drug itself caused problems or whether the mother’s underlying health condition was the real concern. Combining multiple studies together (called a meta-analysis) gives a more reliable answer than any single study alone.

This study has several strengths: it included a very large number of pregnancies (over 800,000), used official health records rather than relying on people’s memories, and adjusted for many other factors that could affect results. However, the study had limited ability to detect very small increases in risk, and the number of babies exposed to statins was relatively small (only 283 pregnancies), which means weak associations might have been missed. The findings are reassuring but not definitive proof of complete safety.

What the Results Show

The main finding was that statin exposure during early pregnancy was not clearly associated with an increased risk of birth defects. Among women who took statins, 6.7% had babies with birth defects compared to 4.3% among women who never took statins. While this appears higher, the difference was small enough that it could easily have occurred by chance.

When researchers adjusted for other health factors and compared women who took statins to women who stopped taking them before pregnancy, there was essentially no difference in birth defect rates. This suggests that if there is any increased risk, it’s very small and might not be caused by the statin itself.

The updated analysis combining this study with previous research found no increased risk of major birth defects or heart defects specifically. The results were consistent across different types of analyses, suggesting the findings are fairly reliable.

The study also examined other cholesterol-lowering medications beyond statins and found no association with heart defects. When researchers looked at different types of birth defects separately (major versus minor), the pattern remained the same—no clear increased risk from statin exposure.

This research updates a 2022 meta-analysis (a summary of previous studies) with new data. The previous analysis had suggested some possible concern, but this larger Norwegian study combined with updated analysis found no strong evidence of harm. The findings are reassuring compared to the traditional medical advice that completely avoided statins in pregnancy.

The study couldn’t detect very small increases in risk because the number of exposed pregnancies was relatively small. Additionally, the study couldn’t determine why some women took statins (their specific health conditions), which might have affected the results. The study also relied on prescription records, so researchers couldn’t confirm that women actually took the medications as prescribed. Finally, this research was conducted in Norway, so results might differ in other populations with different genetics or healthcare practices.

The Bottom Line

Based on this research, the absolute risk of birth defects from statin use in early pregnancy appears to be low or non-existent. However, the decision to use statins during pregnancy should be made individually with your doctor, weighing the benefits for your heart health against any potential risks. This is not a recommendation to start or stop any medication without medical guidance. Confidence level: Moderate—the study is large and well-designed, but some uncertainty remains.

This research is most relevant for women of childbearing age who take statins for high cholesterol or heart disease and are planning pregnancy or have recently become pregnant. It’s also important for their doctors who need to make decisions about continuing or stopping these medications. Women without high cholesterol or heart disease should not start taking statins based on this research. Pregnant women should always discuss medication decisions with their healthcare provider.

Birth defects form during the first three months of pregnancy, so the critical period for this concern is early pregnancy. If you’re taking statins and planning to become pregnant, discuss your medication plan with your doctor before conception. If you’ve already been exposed to statins during early pregnancy, the research suggests the risk is likely very low, but discuss any concerns with your healthcare provider.

Want to Apply This Research?

  • If you’re taking statins and pregnant or planning pregnancy, track your medication adherence and any pregnancy-related health appointments. Log when you take your statin dose and note any discussions with your doctor about continuing or adjusting the medication during pregnancy.
  • Work with your healthcare provider to create a clear medication plan before conception. Use the app to set reminders for medication timing and to schedule regular prenatal appointments where you can discuss your statin use. Document any changes your doctor recommends to your statin regimen.
  • Throughout pregnancy, maintain regular communication with your healthcare team about your statin use. Use the app to track prenatal visits and any concerns about medications. After delivery, continue monitoring your cholesterol levels and medication adherence as recommended by your doctor, since managing your heart health is important for long-term wellness.

This research summary is for educational purposes only and should not replace professional medical advice. Decisions about taking statins or other medications during pregnancy are complex and depend on your individual health situation, including your heart disease risk and the severity of your condition. Always consult with your obstetrician and cardiologist before starting, stopping, or continuing any medication during pregnancy or while planning to become pregnant. This study suggests statins may be safer than previously thought, but it does not constitute medical advice or a recommendation to use or avoid these medications. If you have concerns about medication exposure during pregnancy, discuss them with your healthcare provider immediately.