This sheet is about exposure to miglustat in pregnancy and while breastfeeding. This information should not take the place of medical care and advice from your healthcare provider.
What is miglustat?
Miglustat is a medication that has been used for treatment of mild to moderate Gaucher disease type 1. It has also been used to treat Niemann-Pick disease type C. Miglustat is sold under the brand name Zavesca®.
People with Gaucher disease have low levels of an enzyme called glucocerebrosidase (gloo-co-se-ruh-BRO-si-dace). This enzyme helps break down fatty substances in the body. When this enzyme is missing or not working, fatty substances build up and can cause organ damage. Miglustat works in the body to limit the amount of the fatty substances being made. For more information, see the MotherToBaby fact sheet on Gaucher disease at https://mothertobaby.org/fact-sheets/gaucher-disease-pregnancy/.
Sometimes when people find out they are pregnant, they think about changing how they take their medication, or stopping their medication altogether. However, it is important to talk with your healthcare providers before making any changes to how you take this medication. Your healthcare providers can talk with you about the benefits of treating your condition and the risks of untreated illness during pregnancy.
I take miglustat. Can it make it harder for me to get pregnant?
Studies have not been done in humans to see if miglustat could make it harder to get pregnant.
Does taking miglustat increase the chance of miscarriage?
Miscarriage is common and can occur in any pregnancy for many different reasons. Studies have not been done in humans to see if miglustat could increase the chance for miscarriage. Studies in animals found a greater chance of pregnancy loss at doses around twice as much as would be used in human therapy.
Does taking miglustat 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 miglustat increases the chance for birth defects. Animal studies done by the manufacturer did not find an increased chance of births defects.
Does taking miglustat in pregnancy increase the chance of other pregnancy-related problems?
Studies have not been done in humans to see if miglustat 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). Animal studies done by the manufacturer reported a higher chance of low birth weight.
Does taking miglustat in pregnancy affect future behavior or learning for the child?
Studies have not been done in humans to see if miglustat causes cause long-term problems in behavior or learning.
Breastfeeding while taking miglustat:
There are no studies looking at miglustat use while breastfeeding. The product label for miglustat states that because there is no data available, use during breastfeeding is not recommended. But, the benefit of using miglustat may outweigh possible risks. Your healthcare providers can talk with you about using miglustat and what treatment is best for you. Be sure to talk to your healthcare provider about all of your breastfeeding questions.
If a male takes miglustat, could it affect fertility (ability to get partner pregnant) or increase the chance of birth defects?
In humans, one report did not find that miglustat use in 5 males affected the production of sperm or their fertility. Animal studies in rats found that miglustat exposure lowered sperm production, which lowered fertility. However, this was not found in all animal studies; and some animal strains are more sensitive to this exposure. 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/.
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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.
