Pregnancy in Women With MS Relapses in Year Before Conception Increases Disability Risk

Shot of a pregnant young woman
Study researchers assessed the long-term disability risk following pregnancy in women with multiple sclerosis.

Women with multiple sclerosis (MS) who had a disease relapse during the year prior to pregnancy were associated with increased risk for disability worsening, according to results of a study published in the Multiple Sclerosis Journal.

Researchers from the University of Florence sourced data from the Italian Pregnancy dataset collected at 21 sites across Italy. Women with MS who were pregnant between 2002 and 2008 were matched with women who did not have a pregnancy. Study researchers collected data for the control group at the MS center in Florence. They then assessed clinical outcomes through a mean of 6.5 years.

The pregnancy (n=230) and control (n=102) cohorts comprised women with a mean age of 32.4 and 33.4 years, disease duration at baseline of 6.9 and 6.7 years, and Expanded Disability Status Scale (EDSS) of 1.4 and 1.5, respectively.

More women who had not had a pregnancy spent a longer time on disease modifying drugs (46.1% vs 15.7%, respectively; P <.001).

Study researchers observed that disability progressed among 28.3% of the pregnancy group and 21.6% of the control cohort (P =.201).

Risk for disability progression was associated with relapse in the year prior to conception (adjusted hazard ratio [aHR], 1.74; 95% CI, 1.06-2.84; P =.027), higher baseline EDSS (aHR, 1.39; 95% CI, 1.12-1.74; P =.003), younger age at baseline (aHR, 0.95; 95% CI, 0.91-0.99; P =.022) and those who had shorter exposure to disease-modifying drugs over follow-up (aHR, 0.46; 95% CI, 0.25-0.81; P =.008).

In the pregnancy cohort, disability progression risk was associated with relapse during the post-partum year (aHR, 1.85; 95% CI, 1.11-3.06; P =.018). Longer exposure to disease modifying drugs during follow-up was linked to decreased risk of disability worsening (P <.010).

This study was limited by recruiting the control cohort from a single site and by the fact that none of the included women were treated with fingolimod or natalizumab.

The data indicated that women who relapsed in the year prior to conception were at increased risk for disability progression. Clinicians should be aware of this association and may consider counseling their patients to attempt a pregnancy only during periods of clinical stability.

Disclosure: Multiple authors declared affiliations with the pharmaceutical industry. Please refer to the original article for a full list of disclosures.


Portaccio E, Tudisco L, Pastò L, et al. Pregnancy in multiple sclerosis women with relapses in the year before conception increases the risk of long-term disability worsening. Mult Scler. Published online, June 16, 2021. doi:10.1177/13524585211023365