Atenolol in Pregnancy
Atenolol has been shown to cause temporary or permanent problems to unborn children when taken during pregnancy. For this reason, taking atenolol during pregnancy is generally not recommended. However, a healthcare provider may prescribe it to a pregnant woman if the benefits outweigh the possible risks. A few of the complications sometimes seen with fetuses or newborns exposed to atenolol include small birth weight, low blood sugar, and slowed heart rate.
Use of atenolol (Tenormin®) during pregnancy is generally not recommended. This is because during pregnancy, atenolol can cause temporary or permanent problems to the unborn child.
The U.S. Food and Drug Administration (FDA) uses a category system to classify the possible risks to a fetus when a specific medicine is taken during pregnancy. Atenolol is considered a pregnancy Category D medicine. Pregnancy Category D is given to medicines that have shown clear evidence of risk to the fetus in studies. A pregnancy Category D medicine may still be given to a pregnant woman if the healthcare provider believes that the benefits to the woman outweigh the possible risks to the unborn child.
A few of the complications seen with some fetuses or newborns exposed to atenolol near the end of pregnancy include:
- Low birth weight
- Low blood sugar (hypoglycemia)
- Slowed heart rate (bradycardia).
Studies suggest that the risk of low birth weight increases with the length of time that atenolol is used (with the largest problems seen when women take atenolol for several weeks or more during pregnancy).
There are no adequate studies to know what harm (if any) atenolol might cause if taken in early pregnancy in humans. When given to pregnant rats, the drug increased the risk of miscarriages.