This sheet talks about exposure to nifedipine in pregnancy and while breastfeeding. This information should not take the place of medical care and advice from your healthcare provider.

What is nifedipine?

Nifedipine belong to a group of medications called calcium channel blockers. It is used to treat high blood pressure (hypertension) and chest pain (angina). Sometimes it is used to stop labor before 37 weeks of pregnancy (preterm delivery). Some brand names for nifedipine are Procardia®, Adalat CC®, and Afeditab CR®.

I take nifedipine. Can it make it harder for me to get pregnant?

Studies on women have not been done to see if nifedipine could make it harder for a woman to get pregnant.

I am taking nifedipine, and I just found out that I am pregnant. Should I stop taking nifedipine?

Talk with your healthcare provider(s) before making any changes to this medication. It’s important to make sure any medical conditions you have are treated appropriately, especially during pregnancy. Uncontrolled high blood pressure during pregnancy can cause complications.

Does taking nifedipine increase the chance for miscarriage?

Miscarriage can occur in any pregnancy. Two studies reported a higher number of miscarriages in pregnancies exposed to calcium channel blockers such as nifedipine when compared to pregnancies not exposed to calcium channel blockers. However, the rate of miscarriage among women using calcium channel blockers in the studies was not higher than that of the general population and may be related to the maternal disease rather than the medication used as treatment.

Does taking nifedipine increase the chance of having a baby with a birth defect?

In every pregnancy, a woman starts out with a 3-5% chance of having a baby with a birth defect. This is called her background risk. No well-controlled studies looking at the use of nifedipine in pregnancy have been done. There have been case reports of birth defects, including abnormal limbs and tooth anomalies. There have also been reports of normal outcomes with use of nifedipine in pregnancy. More information about the use of nifedipine in pregnancy is needed to understand if there are any increased risks to a pregnancy. It is important for you and your healthcare provider to consider the benefits of treating your condition during pregnancy and discuss the treatment plan that is right for you.

Could nifedipine cause other pregnancy complications?

Two studies reported that preterm delivery (before 37 weeks) and lower birth weight (less than 6lbs) were more common in patients treated with calcium channel blockers such as nifedipine. However, the authors suggest the cause of these complications is likely due to the maternal illnesses rather than to the medications used.

It is known that complications can happen when a woman has uncontrolled high blood pressure during pregnancy. High blood pressure during pregnancy can increase the risk of heart disease, kidney disease, and stroke. Babies can be smaller than usual (growth restriction) or there can be a preterm delivery. The organ that provides oxygen and nutrients to your growing baby (placenta) may separate from the wall of the uterus too soon (placental abruption). Also, women with high blood pressure may develop pre-eclampsia (high blood pressure and problems with your organs). Pre-eclampsia can lead to seizures (called eclampsia). These conditions are serious and can be harmful to mother and baby.

I need to take nifedipine throughout my entire pregnancy. Will it cause withdrawal symptoms in my baby after birth?

No. Nifedipine has not been shown to cause withdrawal symptoms in babies.

Will taking nifedipine during pregnancy affect my baby’s behavior or cause learning problems?

Studies have not been done to see if nifedipine can affect behavior or cause learning problems in babies whose mothers took this medication pregnancy.

Can I breastfeed my baby if I am taking nifedipine?

Yes. Nifedipine gets into breastmilk in small amounts, which means the amounts ingested by the infant are small. No adverse effects have been reported in babies whose mothers used nifedipine while nursing. If you are worried about any symptoms that the baby has, contact the child’s healthcare provider. Be sure to talk to your health care provider about all of your breastfeeding questions.

What if the baby’s father takes nifedipine?

In a small number of men taking nifedipine to control high blood pressure, nifedipine use may have caused them to become infertile. The infertility was reversed when the medication was stopped. Studies have not looked at the chance of birth defects if a father takes nifedipine. In general, exposures that fathers have are unlikely to increase risks to a pregnancy. For more information, please see the MotherToBaby fact sheet Paternal Exposures and Pregnancy at https://mothertobaby.org/fact-sheets/paternal-exposures-pregnancy/pdf/.

References

• American College of Obstetricians and Gynecologists. (2018, May). Preeclampsia and High Blood Pressure During Pregnancy. Retrieved February 6, 2019, from https://www.acog.org/Patients/FAQs/Preeclampsia-and-High-Blood-Pressure-During-Pregnancy?IsMobileSet=false
• Benoff S, et al. 1994. The effect of calcium ion channel blockers on sperm fertilization potential. Fertil Steril 62:606-17.
• Bortolus R, et al. 2000. Nifedipine administered in pregnancy: Effect on the development of children at 18 months. BJOG 107:792-794.
• Magee LA, et al. 1996. The safety of calcium channel blockers in human pregnancy: A prospective, multicenter cohort study. Am J Obstet Gynecol 174:823-8.
• Tabacova SA, et al. 2002. Developmental abnormalities reported to FDA in association with nifedipine treatment in pregnancy. Teratology;65:368.
• S. National Library of Medicine. (2018). Toxnet- Lactmed: Nifedipine. Retrieved February 6, 2019, from https://toxnet.nlm.nih.gov/newtoxnet/lactmed.htm
• Weber-Schoendorfer C, et al. 2008. The safety of calcium channel blockers during pregnancy: a prospective, multicenter, observational study. Reprod Toxicol 26(1): 24-30.