This sheet is about exposure to voxelotor in pregnancy and while breastfeeding. This information should not take the place of medical care and advice from your healthcare provider.
What is voxelotor?
Voxelotor is a medication that has been used to treat sickle cell disease (a condition that changes the shape of red blood cells). Sickle cell disease can cause issues such as pain, infections, and other health complications. Voxelotor is in a class of medication called hemoglobin S polymerization inhibitors. It is sold under the brand name Oxbryta®.
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 voxelotor. Can it make it harder for me to get pregnant?
It is not known if voxelotor can make it harder to get pregnant. However, having sickle cell disease may make it harder to get pregnant.
Does taking voxelotor increase the chance of miscarriage?
Miscarriage is common and can occur in any pregnancy for many different reasons. Studies have not been done to see if voxelotor increases the chance for miscarriage. Sickle cell disease may increase the chance of miscarriage.
Does taking voxelotor 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. Data from animal studies suggest there is not an increased chance for birth defects when taking voxelotor during pregnancy. Studies have not been done to see if voxelotor increases the chance for birth defects in humans.
Does taking voxelotor in pregnancy increase the chance of other pregnancy-related problems?
Studies have not been done in humans to see if voxelotor 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).
People with sickle cell disease may have an increased chance of preterm delivery, low birth weight, and other pregnancy complications and should be monitored closely by healthcare providers during pregnancy.
Does taking voxelotor in pregnancy affect future behavior or learning for the child?
Studies have not been done to see if voxelotor can cause behavior or learning issues for the child.
Breastfeeding while taking voxelotor:
There is no human data looking at the use of voxelotor in breastfeeding. The product label for voxelotor recommends people who are breastfeeding should not use this medication and should wait to breastfeed until 2 weeks after the last dose. But the benefit of using voxelotor may outweigh possible risks. Your healthcare providers can talk with you about using voxelotor 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 voxelotor, could it affect fertility (ability to get partner pregnant) or increase the chance of birth defects?
Studies have not been done to see if voxelotor could affect male fertility or increase the chance of birth defects above the background risk. One experimental animal study suggested it might lower the chance of pregnancy when males take voxelotor, but this has not been checked in humans. Also, sickle cell disease itself may affect male fertility. In general, exposures that fathers or sperm donors 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/.
Please click here for references.
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.