Is lithium safe during pregnancy?

I am taking lithium but would like to stop taking it before getting pregnant. How long does the drug stay in my body?

The time it takes to metabolize (to process) medication is not the same for everyone. In healthy non-pregnant adults, it takes up to 9 days, on average, for most of the lithium to be gone from the body. Studies have also shown that the longer a person has been on lithium, the longer it might take for their body to clear it completely after stopping the medication.

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

It is not known if lithium can make it harder to get pregnant.

Does taking lithium increase the chance of miscarriage?

Miscarriage is common and can occur in any pregnancy for many different reasons. It is not known if lithium can increase the chance of miscarriage. Two studies reported an increase in miscarriage with use of lithium in pregnancy. However, neither study could control for other important factors, such as other medical conditions or other exposures. A third study did not find an increased chance of miscarriage with lithium use. As there can be many causes of miscarriage, it is hard to know if a medication, the medical condition being treated, or other factors are the cause of a miscarriage.

Does taking lithium increase the chance of birth defects?

Birth defects can happen in any pregnancy for different reasons. Out of all babies born each year, about 3 out of 100 (3%) will have a birth defect. We look at research studies to try to understand if an exposure, like lithium, might increase the chance of birth defects in a pregnancy.

Some studies suggest a small increase in the chance of heart defects with the use of lithium in the first trimester, especially a rare heart defect called Ebstein's anomaly (when one of the valves that controls blood flow in the heart forms in a different place than expected). Other studies have not shown an increased chance of Ebstein’s anomaly or other heart defects with the use of lithium.

Does taking lithium in pregnancy increase the chance of other pregnancy-related problems?

Some studies suggest that using lithium during pregnancy is associated with an increased chance of preterm delivery (birth before week 37). Some studies have reported higher birth weight and low blood sugar in infants following exposure to lithium during pregnancy, while other studies have not reported differences in birth weight. Lithium has not been associated with low birth weight (weighing less than 5 pounds, 8 ounces [2500 grams] at birth). There are case reports of polyhydramnios (too much amniotic fluid around the fetus, which can lead to preterm delivery and other pregnancy complications) with the use of lithium in pregnancy.

Using lithium during pregnancy might cause goiter (when the thyroid gland grows larger than usual) and hypothyroidism (very low activity of the thyroid gland) in people who are pregnant. There are also case reports of these symptoms in babies exposed to lithium during pregnancy. If you are pregnant and taking lithium, talk with your healthcare provider about having your thyroid function monitored throughout pregnancy so you can be treated, if needed.

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

The use of lithium during pregnancy can cause temporary symptoms in newborns soon after birth. These symptoms are sometimes referred to as withdrawal. There have been reports of low muscle tone (floppiness), sedation (sleepiness), trouble with breathing and feeding, and jaundice (yellowing of the skin and eyes). These symptoms were reported when lithium was used near the time of delivery, especially if the mother’s own blood lithium level was high. Not all babies exposed to lithium will have symptoms. It is important that your healthcare providers know you are taking lithium so that if symptoms occur your baby can get the care that is best for them.

Does taking lithium in pregnancy affect future behavior or learning for the child?

Small studies on children 3 to 15 years old who were exposed to lithium during pregnancy did not find significant differences in physical, mental, or behavioral problems when compared to children who were not exposed to lithium during pregnancy.

What screenings or tests are available to see if my pregnancy has birth defects or other issues?

Prenatal ultrasounds can be used to screen for some birth defects, such as Ebstein’s anomaly. Ultrasound can also be used to monitor the growth of the pregnancy. Talk with your healthcare provider about any prenatal screenings or testing that are available to you. There are no tests available during pregnancy that can tell how much effect there could be on future behavior or learning.

If a man takes lithium, could it affect fertility or increase the chance of birth defects?

There are reports of lower sperm quality and less sperm movement with lithium use in men. One of these reports found no effects on men’s fertility (ability to get a partner pregnant). Lower sex drive was reported in another study, but this is a common side effect of depression and might not be due to lithium. In general, exposures that men have are unlikely to increase risks to a pregnancy. For more information, please see the MotherToBaby fact sheet Paternal Exposures at https://mothertobaby.org/fact-sheets/paternal-exposures-pregnancy/ .