MS seems to discriminate on the basis of sex.
Although (interestingly) I've seen claims that PPMS is either sex-neutral or that PPMS skews male, it seems to be a foregone conclusion that when factoring in all four phenotypes of MS, MS skews female as a whole. (The estimates I've seen have ranged from 66% - 80% in favor of women.)
Alarmingly, that disparity has widened.
Quoting University of Alabama professor of biostatistics Gary Cutter, PhD, WebMD reports: "In 1940, twice as many women as men in the U.S. had multiple sclerosis. By 2000, four out of five cases were occurring among women."
This growing disparity suggests something environmental is at play.
Considering that oral contraceptives affect women only, they are a logical suspect. And indeed there is speculation that the rising use of oral contraceptives are a contributing factor to the sex disparity in MS.
Is There A Link Between Oral Contraceptives and MS?
There is evidence that oral contraceptives can delay or prevent the onset of MS or improve the course of MS in women who are actively using them.
There is also evidence that suggests there is positive correlation between oral contraceptive use and the development of MS or Clinically Isolated Syndrome (the precursor to MS).
Citing a 2014 study, the American Academy of Neurology states: "Women who had used hormonal contraceptives were 35 percent more likely to develop MS than those who did not use them."
The study points out that the use of oral contraceptives "has been associated with a modest increase in risk of inflammatory bowel disease (IBD). This is particularly interesting because IBD is the only autoimmune disease with a strong co-morbid association with MS."
Why might this be? As another paper points out, "oral estrogen has been shown to modify intestinal permeability" and hormones are linked to both altered gut microbiome, which is linked to the development of autoimmune diseases.
I think it's likely the case that the prolonged use of oral contraceptives contributes to dysbiosis, which sets the stage for the onset of MS later in life. However, during MS, oral contraceptives (exogenous hormones) provide beneficial effects on the disease course due to their anti-inflammatory effects.
My Very Humble and Unscientific Opinion
It's not my place to suggest you should or shouldn't be on oral contraceptives; I don't know you or anything about your situation.
That said, the decision to give your body a steady dose of synthetic steroids strong enough to prevent your body from ovulating is not one that should be taken lightly.
In recent years we've come to realize physicians have been over prescribing antibiotics, and that's given rise to "superbugs." I think there will come a time when we collectively come to the learn that oral contraceptives have been overprescribed and have contributed to the rise of various maladies.
If you do decide to get off oral contraceptives, it's probably best to taper it off to allow your body's hormone levels time to ease back to their natural levels. Be sure to have that conversation with your doctor.