I've suffered weird digestive things when I have my period. The way I have heard it explained in my MCAT class is that the same hormone that causes the smooth muscle of the uterus to contract unfortunately works on all of our digestive organs as well, particularly the large intestine. So that's how I've come to grips with the apparent confusion of the digestive processes during my period.
It is understandable that your digestive processes are causing confusion every month. Many women experience heightened gastrointestinal problems around the time of their period. However, research is still inconclusive in determining the exact physiological connections between the gastrointestinal (GI) and menstrual systems. One hypothesis is that the GI tract responds to changes in levels of female hormones, and the increased production of prostaglandins (hormone-like substances that directly affect the tissue with which they come in contact, often causing cramping) and progesterone during the menstrual cycle may lead to bloating, diarrhea, and/or constipation. Another suggestion is that some of the over-the-counter drugs recommended to alleviate menstrual pain may contribute to GI upset (e.g., NSAIDS — nonsteroidal anti-inflammatory drugs, such as ibuprofen).
One study in the American Journal of Gastroenterology found that women with Irritable Bowel Syndrome (IBS), or a similar type of Inflammatory Bowel Disease (IBD) such as Crohn's disease or ulcerative colitis, are more likely to experience digestive disturbances during their periods compared to women without chronic bowel problems. Not all women who experience GI inflammation during their period have IBD or IBS, but it's something to check if your symptoms seem extreme. In addition, women with dysmenorrhea (painful cramping during menstruation) are more likely to have functional bowel disorder.
Although no one really knows exactly why digestive symptoms are associated with the onset of menstruation, the good news is that you can help minimize some of these annoyances that you experience. Here's how:
Select or choose carefully what you eat before and during your period
Bring on the fiber; eat whole grains and lots of veggies; hold off on extra salt, dairy, sugar, alcohol, spicy foods, and caffeine.
Use relaxation techniques, such as meditation or yoga, or talk with someone who will listen.
You may want to try adding regular moderate exercise to your routine to help reduce stress and help your digestive system function more smoothly.
It might be helpful to keep a journal of your GI symptoms on the days leading up to your period. If you can identify patterns with your symptoms and the food you eat, how much you are exercising, or any other behaviors you notice, you may be able to customize a plan for smooth sailing through PMS and your period. Best of luck!Alice!