Date: July 2021, Version 2

What is it?

Ustekinumab (also known as Stelara®) is a medicine that dampens the immune response. It is used to treat some autoimmune diseases, including plaque psoriasis, psoriatic arthritis, Crohn’s disease and ulcerative colitis.


What are the benefits of using ustekinumab in pregnancy?

Ustekinumab helps to stop the immune system from attacking the body. It controls the unpleasant and often disabling symptoms of some autoimmune diseases, and helps to prevent ongoing damage to tissues and organs. It can also reduce the risk of some adverse pregnancy outcomes that have been linked to poorly controlled autoimmune disease, including miscarriage, preterm delivery and low infant birth weight.


Are there any risks of using ustekinumab during pregnancy?

The small amount of data available suggests that ustekinumab is unlikely to harm the baby but further studies are ideally required.

There are concerns that ustekinumab might affect the baby’s immune system for a while after birth; because of this, live vaccines might be harmful. It is therefore recommended that babies exposed in the womb to ustekinumab do not receive live vaccines until they are at least six months old. In practice, this means that these babies will not be able to receive the rotavirus vaccine course (as this must be complete by four months of age), and if BCG vaccination is required it will be delayed until the baby is six months old.


Are there any alternatives to using ustekinumab in pregnancy?

Yes; other immunosuppressant medicines can be used in pregnancy so switching to a different drug may be an option. Some women may also find that their illness improves by itself as pregnancy progresses, and so a specialist may advise that treatment can be reduced.

Women on ustekinumab who are planning a pregnancy or who accidentally conceive should arrange to see their doctor or specialist as soon as possible. This is to check whether ustekinumab is still the best treatment and to make sure the dose is correct.

Pregnant women are advised not to change or stop their medication without speaking to their doctor.

No treatment

What if I prefer not to use ustekinumab during pregnancy?

Pregnant women who have poorly controlled autoimmune disease may be at risk of adverse pregnancy outcomes, including miscarriage, preterm delivery and low infant birth weight. To help reduce the chance of these outcomes and to stop an autoimmune disease from flaring, some women will be advised to continue taking ustekinumab in pregnancy. A doctor will only prescribe medicines when necessary and will be happy to talk through about any concerns that you may have.

Will I or my baby need any extra monitoring?

As part of routine antenatal care, most women will be offered a very detailed scan at around 20 weeks of pregnancy to check the baby’s development. Because there is not much information on ustekinumab use in pregnancy, women taking this may be offered extra monitoring as a precaution.

Are there any risks to my baby if the father has used ustekinumab?

There is currently no evidence that ustekinumab used by the father can harm the baby through effects on the sperm.

Who can I talk to if I have questions?

If you have any questions regarding the information in this leaflet please discuss them with your health care provider. They can access more detailed medical and scientific information from

How can I help to improve drug safety information for pregnant women in the future?

Our online reporting system (MyBump Portal) allows women who are currently pregnant to create a secure record of their pregnancy, collected through a series of questionnaires. You will be asked to enter information about your health, whether or not you take any medicines, your pregnancy outcome and your child's development. You can update your details at any time during pregnancy or afterwards. This information will help us better understand how medicines affect the health of pregnant women and their babies. Please visit the MyBump Portal to register.

General information
Sadly, miscarriage and birth defects can occur in any pregnancy.

Miscarriage occurs in about 1 in every 5 pregnancies, and 1 in every 40 babies are born with a birth defect. This is called the ‘background risk’ and happens whether medication is taken or not.

Most medicines cross the placenta and reach the baby. For many medications this is not a problem. However, some medicines can affect a baby’s growth and development.

If you take regular medication and are planning to conceive, you should discuss whether your medicine is safe to continue with your doctor/health care team before becoming pregnant. If you have an unplanned pregnancy while taking a medicine, you should tell your doctor as soon as possible.

If a new medicine is suggested for you during pregnancy, please make sure that the person prescribing it knows that you are pregnant. If you have any concerns about a medicine, you can check with your doctor, midwife or pharmacist.

Our Bumps information leaflets provide information about the effects of medicines in pregnancy so that you can decide, together with your healthcare provider, what is best for you and your baby.