Ankylosing spondylitis (AS) is a form of chronic inflammatory arthritis that most often affects the joints in the spine and lower back. Most people with AS develop it before or during their reproductive years.

For someone with AS who is pregnant or wants to be, it is important to have a plan for safely managing AS symptoms during and after the pregnancy.

Below, we describe how to prepare and how pregnancy can affect AS activity, symptoms, and treatment. We also provide self-care tips for managing AS at this time.

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As the Arthritis Foundation notes, pregnancy planning is especially important for people with AS. Some considerations include:

  • whether it is a good idea to have imaging scans before conceiving
  • which current medications will be safe during the pregnancy
  • how AS symptoms may change during and afterward
  • whether AS will affect birthing plans
  • any necessary plans for childcare or additional help after the birth

When possible, a person with AS should discuss these considerations with a rheumatologist and obstetrician before conceiving.

According to the Autoimmune Association, having AS does not affect fertility or a baby’s health. And people with AS are not more likely to experience pregnancy loss.

AS activity and symptoms may change throughout pregnancy and the postpartum period.

A small 2018 study investigated AS activity at several points before, during, and after pregnancy in 166 women. The team found that the highest levels of AS activity occurred in the second trimester — 45% of the participants experienced AS symptoms during that period.

The high levels of AS activity in the second trimester corresponded with the worst levels of self-reported pain. The participants reported the lowest levels of pain around 6 weeks postpartum. The group had regained their pre-pregnancy functionality at 1 year postpartum.

A 2021 review found that 25–80% of pregnant women with AS experienced a flare of symptoms during pregnancy, and 30–100% experienced a flare in the postpartum period.

These findings suggest that AS symptoms worsen during pregnancy. However, the Arthritis Foundation says that AS activity has equal chances of worsening, staying the same, or decreasing during pregnancy.

It is important for people with AS who are pregnant or planning a pregnancy to consult a doctor about which medications will be safe.

In 2020, the American College of Rheumatology released new guidelines for managing reproductive health in people with rheumatic and musculoskeletal diseases, such as AS.

The guidelines conditionally recommend continuing treatment with some tumor necrosis factor inhibitors (TNFIs) during pregnancy. Among these are infliximab (Remicade), etanercept (Enbrel), and adalimumab (Humira).

And they strongly recommend continuing treatment with one type of TNFI, called certolizumab pegol (Cimzia), because this is present at the lowest levels in the blood of the fetus.

Some other AS treatments include secukinumab (Cosentyx) and ixekizumab (Taltz). However, it is unclear whether these are safe to use during pregnancy.

A person may also use nonsteroidal anti-inflammatory drugs to help manage symptoms such as pain and stiffness. However, people should avoid using these drugs, such as ibuprofen (Advil, Motrin) and celecoxib (Celebrex) in the final 8 weeks of pregnancy.

The AARDA also reports that in some cases, it may be advisable to continue taking a medication, even when this is not completely free from risk.

A person should only stop taking a medication if their doctor recommends it.

According to the Autoimmune Association, no evidence suggests that AS increases the risk of complications during pregnancy.

The condition does not appear to increase the risk of:

However, a 2016 case control study with 388 participants found that higher disease activity during pregnancy may lead to a higher chance of preterm delivery and low birth weight.

Overall, a person with AS may give birth to a healthy baby on or around their due date, regardless of AS activity and symptoms. However, if AS is active, close follow-up with a rheumatologist and obstetrician is important.

Anyone concerned about how their AS will affect their pregnancy should contact a doctor.

A doctor can provide specific information about the most appropriate delivery method, based on a person’s unique symptoms and circumstances.

Will a vaginal delivery be possible?

In most cases, people with AS can have vaginal deliveries. However, people with AS may find a vaginal delivery more difficult than other people, due to the involvement of the hip joints and spine.

The 2016 study found that people with AS are more likely to need emergency or planned cesarean deliveries, compared with people who do not have AS.

Will an epidural be possible?

Increased swelling around the spine can make an epidural more difficult to administer. Prior to delivery, a person may want to consult their doctor or an anesthesiologist about the feasibility of an epidural and other options for pain relief.

The Global Healthy Living Foundation cites evidence that around 60% of women with AS have a flare of symptoms within 6 months of childbirth. And, it reports, anyone who found it challenging to control AS symptoms prior to pregnancy may have extra pain or stiffness afterward.

Before giving birth, discuss breastfeeding plans with a doctor. They can describe whether current AS medications will be safe, and they may recommend alternates, if necessary.

The Arthritis Foundation explains that most AS medications are safe to take while breastfeeding, but it is a good idea to confirm the safety with a healthcare professional.

Anyone who has AS-related pain or stiffness while picking up or holding their baby might consider a supportive device. In some cases, simply propping up the baby on a pillow can help support their weight and ease the pain.

AS is an autoimmune disorder that has a genetic component. However, this does not mean that if a person has AS, their child will eventually develop it. Many people with autoimmune disorders such as AS have children that never develop these issues.

These tips may help prevent or manage AS symptoms during pregnancy:

  • Discuss pregnancy plans ahead of time with a doctor. This gives them the necessary time to adjust AS medications and other therapies.
  • Use heating pads or cool packs on sore or sensitive areas.
  • Make plans for childcare or additional help before the delivery — fatigue may worsen around this time.

When preparing for pregnancy, a person with AS should discuss any necessary changes to the treatment plan with a doctor, learn about safe birthing options, and arrange for additional help following the delivery.

AS symptoms can flare during or after pregnancy, but little evidence suggests that having AS increases the risk of pregnancy complications.