Digestion Changes with the Menstrual Cycle

Digestion Changes with the Menstrual Cycle

31 August 2017 by Caitlin Armit

Digestion Changes with the Menstrual Cycle

This topic keeps cropping up during consultations with female patients so I thought I could make the most of this opportunity to discuss why women may experience digestion changes with their menstrual cycle and what the implications of this are for treatment.  

Many women report that during the second half of their menstrual cycle they experience constipation, gas and bloating but as soon as their period begins they experience diarrhoea. The contrast may be extreme for some women and subtle for others. Either way, there’s an explanation for this and it’s all to do with your hormones. So let’s do a very basic review of the hormone changes during your cycle. 

During the first half of your cycle (the follicular phase – day 1 of menstruation until ovulation around day 14) more oestrogen is produced than progesterone as oestrogen is required to prepare the egg for ovulation. This is also known as the proliferative phase as the endometrium, or lining of the uterus, thickens.  

During the second half of your cycle (the luteal phase or post ovulation – approximately day 14 to day 28) progesterone is produced by the ovary and the uterine lining secretes nutrients in case conception occurs. When progesterone levels drop low enough, around day 28, this triggers menstruation. If conception has occurred, progesterone levels remain high and there is no menstruation.  

Elevated progesterone levels can slow the contractility of the digestive tract causing bloating, reflux, gas and constipation – symptoms which are common during pregnancy. This may be due to the presence of sex hormone receptors along the gastrointestinal tract. These same symptoms can occur in the second half of a woman’s cycle if she is not pregnant, and the contrast of high progesterone levels moving to low progesterone levels at the onset of menstruation can result in changes in gut motility – hence the alternation from constipation to diarrhoea or somewhere on that spectrum.  

Prostaglandins (inflammatory markers) in the body are also associated with changing bowel habits during menstruation. A research article published in 1992 indicated that women who experienced diarrhoea during their period also had higher levels of prostaglandins in their body. Prostaglandins contribute to uterine cramping and aching because they cause the uterus to shed lining during menstruation. This also causes increased gut motility, pushing the contents of your digestive system through a little faster. Another study from 2002 confirmed that women with Irritable Bowel Syndrome (IBS) were more likely to notice a change in bowel habits before their period compared to during their period.  

Later in 2014, researchers examined whether there was a relationship between changes in menstrual cycle and a diagnosis of Irritable Bowel Disease within 1 year prior to diagnosis. Of the 121 participants, 21% experienced changes in the duration of menstrual flow, 40% of those with dysmenorrhea experienced changes in intensity of menstrual pain and 31% experienced changes in menstrual duration. Quality of life was significantly lower in those women who did not have regular cycles. Another study, also from 2014, found similar results for IBD patients with restorative proctocolectomy and ileal pounch-anal anastomoses (IPAA).  

The Chinese Medicine Approach

Chinese Medicine is all about balancing yin and yang – two opposing forces which mutually depend on and compliment each other and that are present in everything. In Chinese Medicine, the first half of the menstrual cycle is the ‘yin’ phase because it relates to growth, structure, coolness and moistening; the second half of the menstrual cycle is the ‘yang’ phase of the cycle because it relates to function, movement, warming and activity. Problems with menstruation, digestion, fertility and other systems in the body are essentially an imbalance of yin and yang – perhaps excess of one or deficiency of another. It may involve one organ or system but more commonly involves two or three. The nuts and bolts of treatment with acupuncture and Chinese Medicine is to nourish where something is deficient and sedate or reduce where something is in excess. We call it yin hormones and yang hormones – Western Medicine calls it oestrogen and progesterone. We call it yin phase and yang phase – Western Medicine calls it the follicular phase and the luteal phase. The goal of treatment is to achieve regular cycles and balance hormones by selecting appropriate acupuncture points and herbs to address the Chinese Medicine diagnosis. We also select acupuncture points to benefit digestion, whether the necessary mechanism involves stimulating bile production to lubricate the intestines or regulating peristalsis (the natural contraction of the walls of the gastrointestinal system) to move food through the body.

What To Do 

If you’re unsure about whether there is a pattern for you with your bowel movements and your cycle, try keeping a daily diary over two months so that you can look back and examine it. Tracking your menstrual cycle can be an eye opening experience, especially if you’re recording other health information at the same time. As always, it’s important to maintain a high fibre diet loaded with vegetables and exercise regularly to keep your qi moving.  It’s also wise to be aware of changes in your stress levels in the second half of your cycle and modify life accordingly. If PMS tends to get the better of you, the second half of your cycle probably isn’t the best time to be making life changing decisions or running yourself into the ground with to-do lists and social obligations. Appropriate diet and exercise are crucial in Chinese Medicine. It’s not just about acupuncture and herbs because this is a system of holistic healthcare which is deeply rooted in philosophy around lifestyle choices and longevity.



Prostaglandin metabolism in relation to the bowel habits of women.

The menstrual cycle affects rectal sensitivity in patients with irritable bowel syndrome but not health volunteers.

Menstrual Cycle Changes in Women with Inflammatory Bowel Disease: A Study from the Ocean State Crohn’s and Colitis Area Registry 

Association between gastro-intestinal symptoms and menstruation in patients with ileal pouches 

Symptomatology of irritable bowel syndrome and inflammatory bowel disease during the menstrual cycle 

Expert Commentary – Bloating, Distension, and the Irritable Bowel Syndrome


Categories: Digestive Health Brisbane | Women's Health Brisbane

Tags: | | | | | |