TUESDAY, Sept. 22, 2020 (HealthDay News) — Pregnancy is associated with a delay in the onset of multiple sclerosis by more than three years, according to a study published online Sept. 14 in JAMA Neurology.
Ai-Lan Nguyen, M.B.B.S., from the Royal Melbourne Hospital in Australia, and colleagues investigated the association of pregnancy with time to clinically isolated syndrome (CIS) onset among 2,557 adult women being treated at the multiple sclerosis outpatient clinics of four tertiary hospitals in the Czech Republic and Australia.
The researchers found that the mean age at CIS onset was 31.5 years. Before CIS onset, 46 percent of women had at least one pregnancy and 43 percent had at least one childbirth. Onset of CIS was later among women with previous pregnancies and childbirths versus those who had never been pregnant (hazard ratio, 0.68), with a median delay of 3.3 years. Similarly, CIS onset was later among women who had given birth versus women who had never given birth (hazard ratio, 0.68), with a median delay of 3.4 years. However, there was no delay in CIS onset with higher gravidity and parity.
“Findings of this study suggest that future research is needed to explore the mechanisms underpinning the association between pregnancy and timing of the first presentation of multiple sclerosis,” the authors write.