Many women feel that their MS symptoms get worse two or three days before their period starts, and get better once bleeding has started. If you feel that this is the case for you, you are not alone. You can take steps to reduce the impact that your symptoms have on your life.
Some small studies have confirmed this anecdotal evidence, but found that the effect was limited to women with RRMS who were not taking oral contraceptives. If you are taking a combined oral contraceptive, you are unlikely to notice an effect. The hormones in oral contraceptives may already be affecting your menstrual cycle.
A more recent and much large study found no evidence for cyclical changes in MS symptoms. They actually found that women with MS generally reported more menstrual symptoms than other women. As a woman with MS, you may simply be more aware of your symptoms, or have other issues with your health or mental health that could make symptoms more noticeable.
You may have found that your menstrual cycle became more irregular after being diagnosed with MS. It is also possible that relapses are more likely in the few days before your period starts, or around the time of first menstruation.
One difficulty with researching this topic is that women are often being asked to remember symptoms and events from many years ago. There is also considerable overlap between what is considered an MS symptom, and what could be considered a regular pre-menstrual symptom. Fatigue, arm and leg weakness, pain and nocturia (the need to go to the toilet during the night) are the symptoms that are usually mentioned. These could be attributed either way.
If you are receiving treatment with a beta interferon drug, you might experience irregular bleeding, early or late periods. You might wish to get a referral to a gynaecologist if this is a concern.