This sheet is about exposure to molnupiravir in pregnancy and while breastfeeding. This information should not take the place of medical care and advice from your healthcare provider.
What is molnupiravir?
Molnupiravir is an investigational antiviral medication. Investigational (or experimental) drugs are ones that are being studied to see if they work. Molnupiravir is being studied for the treatment of SARS-CoV-2 (which causes COVID-19). Molnupiravir is given by mouth (orally). A brand name for molnupiravir is Lagevrio®. For this medication to be effective, it must be started within 5 days of having symptoms of COVID-19.
Because molnupiravir is still being studied, there is limited information on its benefits or risks. However, the U.S. Food and Drug Administration (FDA) gave emergency permission for molnupiravir to be used to treat some patients with mild-to-moderate COVID-19 infection. COVID-19 infection can increase the chance of pregnancy complications. For more information about COVID-19, please the see the MotherToBaby fact sheet at https://mothertobaby.org/fact-sheets/covid-19/.
According to the emergency use label, the use of molnupiravir is not recommended during pregnancy based on animal data that suggests a possible concern. However, your healthcare providers can talk with you about the benefits of treating your condition and the risks of untreated illness during pregnancy.
I am taking molnupiravir, but I would like to be finished with taking it before becoming pregnant. How long does the drug stay in my body?
People eliminate medication at different rates. In non-pregnant adults, it takes up to 1 day, on average, for most of the molnupiravir to be gone from the body. However, it is recommended by the emergency use label that females avoid trying to get pregnant during the time they are taking molnupiravir and for 4 days after the last dose of molnupiravir.
I take molnupiravir. Can it make it harder for me to get pregnant?
Studies have not been done to see if molnupiravir can make it harder to get pregnant. It is recommended by the emergency use label that females who can get pregnant use effective contraception correctly and consistently while they are taking molnupiravir and for 4 days after the last dose of molnupiravir.
Does taking molnupiravir increase the chance for miscarriage?
Miscarriage can occur in any pregnancy. Animal studies suggested an increased chance for miscarriage. Studies have not been done in humans to see if molnupiravir increases the chance for miscarriage. It is not known whether COVID-19 infection itself increases the chance of miscarriage.
Does taking molnupiravir increase the chance of birth defects?
Every pregnancy starts out with a 3-5% chance of having a birth defect. This is called the background risk. Studies have not been done in humans to see if molnupiravir does or does not increase the chance for birth defects above the background risk. Animal studies by the manufacturer suggest an increase in birth defects when molnupiravir was given at 8 times the human dose. These birth defects involved the eyes, kidneys, and some bones. It is not known whether COVID-19 infection can increase the chance of birth defects.
Does taking molnupiravir in pregnancy increase the chance of other pregnancy-related problems?
Studies have not been done in humans to see if molnupiravir increases the chance for pregnancy-related problems such as preterm delivery (birth before week 37) or low birth weight (weighing less than 5 pounds, 8 ounces [2500 grams] at birth). An animal study reported lower fetal weight and a lower amount of mineralized bone (delayed ossification) when molnupiravir was given at 3 times the human dose. At this dose, other effects on fetal development, miscarriage, or stillbirth were not seen.
There is evidence to suggest that COVID-19 infection increases the chance of stillbirth or the mother dying during childbirth. Other negative pregnancy outcomes that appear to be related to COVID-19 include spontaneous preterm delivery, fetal growth restriction, and bleeding in the mother after birth (postpartum hemorrhage).
Does taking molnupiravir in pregnancy affect future behavior or learning for the child?
Studies have not been done to see if molnupiravir can cause behavior or learning issues for the child.
Breastfeeding while taking molnupiravir:
The emergency use label for molnupiravir recommends people who are breastfeeding not use this medication. But, the benefit of using molnupiravir while breastfeeding may outweigh possible risks. People who are breastfeeding may consider pumping and discarding breast milk during treatment with molnupiravir and for 4 days after the last dose. Your healthcare providers can talk with you about using molnupiravir and what treatment is best for you and your baby. Be sure to talk to your healthcare provider about all of your breastfeeding questions.
If a male takes molnupiravir, could it affect fertility (ability to get partner pregnant) or increase the chance of birth defects?
Studies have not been done to see if molnupiravir could affect male fertility or increase the chance of birth defects. The product label notes that, while the risk is considered to be low, it is recommended that males use a reliable method of contraception correctly and consistently during treatment and for at least 3 months after the last dose of molnupiravir. In general, exposures that fathers or sperm donors have are unlikely to increase the risks to a pregnancy. For more information, please see the MotherToBaby fact sheet Paternal Exposures at https://mothertobaby.org/fact-sheets/paternal-exposures-pregnancy/.
MotherToBaby is conducting observational studies looking at COVID-19 in pregnancy. If you had or have suspected or confirmed COVID-19 within 1 month of your last menstrual period or anytime in pregnancy or breastfeeding and you are interested in learning more about this study, please call 1-877-311-8972 or visit https://mothertobaby.org/join-study/.
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OTIS/MotherToBaby encourages inclusive and person-centered language. While our name still contains a reference to mothers, we are updating our resources with more inclusive terms. Use of the term mother or maternal refers to a person who is pregnant. Use of the term father or paternal refers to a person who contributes sperm.