Medications during pregnancy


In general, the evidence suggests that active Crohn’s or UC may do more harm to the growing baby than most IBD medicines. So most women will be advised to continue taking their IBD medication during pregnancy. This is particularly important if you have had a recent flare-up and are trying to get it under control.

However, a small number of the drugs used for IBD are not recommended or should not be used at all by pregnant women. This means that if you are, or are planning to be, pregnant, it is important to check with your IBD team whether you need to change your drug treatment. More details on how the most common IBD drugs might affect your pregnancy are given below.


Aminosalicylates (5-ASAs):

  • Sulphasalazine (Salazopyrin)
  • Mesalazine (Asacol, Pentasa, Salofalk)
  • Olsalazine (Dipentum)
  • Balsalazide (Colazide). These drugs are used to treat mild to moderate flare-ups of IBD and to maintain remission. They have been taken by women during pregnancy for many years, and are generally considered to be safe. Sulphasalazine can reduce the body’s ability to absorb folic acid, a vitamin known to be important to fetal development. So, if you are pregnant and on sulphasalazine, you will be advised to take higher levels of folic acid supplements.

Corticosteroids (steroids):

  • Prednisolone and Budesonide (Entocort). These steroids are widely used to treat IBD flare-ups. Such steroids can cross the placenta but are quickly metabolized, and so are usually considered to be safe in pregnancy. Some early research linked prednisolone treatment with a slightly increased risk of cleft palate, but more recent studies have not supported this finding. Research on the use of budesonide by pregnant women with IBD is currently very limited, but what there is has not shown any harmful effects. Steroids are sometimes prescribed to be taken topically, as an enema or a suppository. These are also safe to use while pregnant.


  • Azathioprine (Imuran) and Mercaptopurine (6-MP) (Purinethol). Immunosuppressant drugs make the body’s immune system less responsive. This has the effect of reducing the inflammation typical of IBD. However, a less responsive immune system may make you more susceptible to infections. Azathioprine and mercaptopurine both cross the placenta and there have been a large number of studies looking at their effects when taken by pregnant women with IBD. Most studies have shown these drugs to be safe, although there is some suggestion they may increase the risk of a preterm birth. In general, most doctors recommend the continued use of azathioprine and mercaptopurine during pregnancy, as the risk from the drug is usually much lower than the risk to the baby if the mother’s IBD relapses. If you do have any concerns, talk to your specialist about the possible risks and benefits, so that your decision can be based on your own health.
  • Methotrexate. Methotrexate can increase the risk of birth defects or miscarriages if taken by women at conception or during pregnancy. It may also affect the formation of sperm. Therefore, it is very important that methotrexate should not be taken by either partner when trying to conceive, or by women when pregnant. Because traces of methotrexate can remain in body tissue for some time, couples are advised to use reliable contraception while being treated with methotrexate and to avoid pregnancy for at least 3-6 months after stopping treatment with this drug. If you find you are pregnant or decide you would like to have a child while on methotrexate, talk to your doctor about this. Women who are the partner of a man taking methotrexate should also talk to their doctor if they discover they are pregnant or wish to conceive.
  • Mycophenolate Mofetil. This immunosuppressant may also cause miscarriages or birth defects if used during pregnancy. Women being treated with this drug who wish to become pregnant are usually advised to stop taking mycophenolate mofetil at least 6 weeks before conception.

  • Ciclosporin. This is a strong immunosuppressant usually prescribed for people with active UC that has not responded to steroids. It can be very effective and help to reduce or avoid the need for surgery. Ciclosporin is known to cross the placenta. Studies of its use in pregnant transplant patients and in a much smaller number of pregnant women with IBD suggest ciclosporin does not seem to harm the unborn baby. However, it can have quite severe side effects, including hypertension (high blood pressure). So ciclosporin is not usually recommended in pregnancy unless there is a real risk that, without it, the mother will need an urgent colectomy (surgery to remove the bowel).

  • Tacrolimus. This is another immunosuppressant originally used to treat transplant patients. There is currently little evidence about its safety for pregnant women with IBD. So if you are taking tacrolimus, and you are pregnant, or thinking about becoming pregnant, it is best to talk to our IBD team about your treatment.


  • Infliximab (Remicade®)

  • Adalimumab (Humira®)\

  • Golimumab (Simponi®)

  • Ustekinumab (Stelara®)

  • and biosimilars: Infliximab (Inflectra®)

These biologic drugs are increasingly used for moderate to severe IBD.

Both infliximab and adalimumab cross the placenta to the baby from about month 6 of the pregnancy.

Research is continuing into the possible effects of these drugs in pregnancy. Several studies have found that the birth outcomes for women with IBD on antiTNF therapy while pregnant have been very similar to those for women not using anti-TNFs. Also, a recent major review concluded that, while it was still too early to say that infliximab and adalimumab are absolutely safe, there is a growing body of evidence that they are low risk during conception and for at least the first two trimesters (up to 6 months).

Currently, the manufacturers of infliximab and adalimumab still recommend caution and the use of contraception to avoid pregnancy. However, many doctors now consider that if the anti-TNF treatment is keeping the IBD in check, it may be better to continue with it during pregnancy, for at least the first six months. In some circumstances, a doctor may advise continuing with anti-TNFs throughout a pregnancy.

Guidelines suggest that doctors should discuss the risks and benefits of these drugs with each woman on an individual basis. You may find it helpful to talk through your own options with your specialist IBD team.

It is also important to be aware that babies of women who have received infliximab or adalimumab during their pregnancy should not be given ‘live’ vaccinations until the age of six months. Your doctor will be able to give you more information on this.


  • Metronidazole and Ciprofloxacin. These antibiotics are sometimes used to treat infections linked to Crohn’s Disease or pouchitis following IPAA surgery. Metronidazole is generally regarded as low risk in pregnancy after the first trimester (months 1-3). Recent research has suggested that it may also be safe for use in early pregnancy. Ciprofloxacin is a type of medication that research in animals has linked to bone problems. Although it has not been shown to be harmful to humans, some doctors advise against using this antibiotic during pregnancy, particularly during the first trimester.


  • Colestyramine (Questran). This is a bile salt binding drug often used to treat diarrhea associated with surgery for Crohn’s. It is considered safe to take during pregnancy.

  • Diphenoxylate (Lomotil)

  • Loperamide (Imodium, Arret)

There is some evidence that loperamide may be linked with birth defects if taken during the first trimester (months 1-3). Guidelines suggest diphenoxylate should be used with caution. It is generally best to check with your doctor before taking these medicines when pregnant.


  • Hyoscine butylbromide (Buscopan). This over-the-counter medicine is best avoided during pregnancy.

For more information on drugs and medicines for IBD, see our specific IBD treatment section.