Menstruation: Irregularities and Symptom Changes

Many women with inflammatory bowel diseases like Crohn’s disease and Ulcerative Colitis report changes in their menstrual cycle.¹ They also may have changes in digestive symptoms throughout the menstrual cycle. However, the link between menstruation and digestive function is not well understood.

Inflammatory bowel disease (IBD) is most often diagnosed between the ages of 15 and 35.² This range includes the peak reproductive years for women.³ Therefore, it is important to understand how IBD and menstruation affect each other.

IBD and period irregularities

Normally, a woman gets her period every 28 days, give or take about 4 days.⁴ A woman’s first period is typically between ages 8.5 and 13 years. Women continue to have a period until menopause. The average age at menopause is 51 years.

Delayed puberty. On average, girls with IBD go through puberty later.⁵ In one study, nearly three-quarters of girls with Crohn's disease got their period at or after age 16 years. Inflammation and difficulty with weight gain are some of the reasons why puberty is delayed.⁵

Socially, it can be difficult to go through puberty later than your friends. Delayed puberty also has an effect on growth and bone health. Hormone changes cause a growth spurt just before you stop growing.⁵ If you go through puberty late, you may have less of a growth spurt.⁵

Changes in menstrual cycle

Menstrual abnormalities. In a survey of women with inflammatory bowel disease, 60% reported having menstrual abnormalities.¹ The abnormalities included very heavy bleeding (menorrhagia) and irregular cycles.¹ In theory, the stress of having a chronic disease, surgery, or difficulty eating a balanced diet could cause changes in your cycle.⁴ However, very little research has been published about this.

In another study, 176 women were asked about changes in their menstrual cycle in the year before they were diagnosed with IBD.³ About one-quarter reported changes in the length of their cycle. Another 20% reported that the number of days of menstrual flow changed. There was no consistent pattern to the change in cycle length and flow duration. Some women reported an increase and others reported a decrease. About 40% of women reported pain during their period. Of this group, one-third reported that it had gotten worse before their diagnosis. The women in this study reported that over time, their cycles became much more regular.

Changes in menstrual symptoms. Menstrual symptoms have not been well studied in women with IBD. One small study showed that there was no differences in premenstrual symptoms overall.⁶ However, certain symptoms were more common in women with inflammatory bowel disease than in the comparison group. These symptoms were headaches, anxiety, depression, and breast pain.

IBD, bowel symptoms, and periods

About half of women with IBD report that their bowel symptoms get worse just before and during their period.⁷ (Interestingly, many women without IBD report the same.⁶) Hormones called prostaglandins might have a role. The lining of the uterus (endometrium) releases prostaglandins. These hormones help the uterus to contract during a period. Prostaglandins also help smooth muscles in the digestive tract to contract. This can lead to diarrhea and abdominal pain.⁸ Prostaglandins also have a role in inflammation.⁸ Other links between bowel symptoms and the menstrual cycle are less clear. Estrogen and progesterone seem to affect movement of food through the digestive tract. They also affect pain perception and sensitivity to changes in internal organs.⁴

Studies have provided the some statistics about women with IBD (Table).⁷

Table. Bowel Symptoms and Menstruation

Source: Bernstein MT, et al. Aliment Pharmacol Ther. 2012;36:135-144.

Only one-third of patients reported that their bowel symptoms improved after menopause.⁷

Medications for menstrual disorders

Questions about whether birth control pills influence IBD development or flares have not been fully answered.⁸ Once you have been diagnosed with IBD, NSAIDs are not recommended.⁹ However, research about the link between medications and IBD is ongoing and so far, inconclusive. No studies have shown that taking these medications is a cause of IBD.²