Celiac disease is an autoimmune disorder in which damage to the inner lining of the small intestine occurs after eating gluten. In individuals with the disease, gliadin, a grain protein in gluten, triggers an immune response that results in flattening and altering of the millions of microscopic finger-like projections (villi) lining the inner wall of the small intestine. Damaged villi cannot carry out their function of helping the body absorb the essential nutrients from food that are necessary to maintain good health. The only treatment is a strict adherence to a gluten-free diet. Current estimates put the prevalence of celiac disease at about 1% of the Canadian population.
In 1970, researchers first made a tenuous connection between celiac disease and reproduction when they found that three previously infertile patients successfully became pregnant after initiating a gluten-free diet.1 Since then, scientists have not made much definitive progress addressing the effects of the disease on pregnancy complications. However, in 2015 another team of researchers undertook the largest study to date of American women with celiac disease to clarify pregnancy outcomes.2
More risks involved for women with celiac disease
The researchers recruited participants through the Jefferson Celiac Center and two national US non-profit organizations – the National Foundation for Celiac Awareness and the Gluten Intolerance Group. Interested individuals then completed an anonymous, online survey of 43 questions that queried the following items: method of diagnosis (small bowel biopsy, serology, trial gluten-free diet); fertile lifespan as measured by their age at the beginning of menstruation (menarche) and end (menopause); and pregnancy complications including miscarriages, preterm births and methods of delivery. For the analysis, they included only the 329 survey participants whose doctors diagnosed them as a result of a small bowel biopsy (which assures accuracy); 641 healthy women acted as the control group.
Of the 970 women included in the study, 75% of those with celiac disease and 76% of the control group had become pregnant at least once. However, when the authors examined how many of the pregnancies resulted in births, only 80% of the women with celiac disease who tried to conceive a child eventually gave birth, compared to 85% of those in the control group. Furthermore, women with celiac disease experienced significantly more complications with their pregnancies than their counterparts. Of the celiac patients, 51% experienced at least one miscarriage, compared to 41% of those in the control group. Lastly, of women who gave birth, 24% of those with celiac disease reported at least one premature birth compared to only 16% of those unaffected. Overall, the authors’ findings suggest that women with celiac disease have a greater risk of encountering pregnancy complications than those without.
The researchers note that many individuals with celiac disease have no obvious symptoms, which delays diagnosis. Since they are unaware of their disease, they are likely continuing to consume gluten that damages their intestines. This can cause malabsorption of zinc, selenium, iron, and folate, which are vital nutrients necessary for a healthy pregnancy.
Other studies have suggested that, after a diagnosis, initiating a gluten-free diet can help women with celiac disease conceive and give birth successfully. For example, Italian researchers found that women with celiac disease were nine times less likely to have a miscarriage if they followed a completely gluten-free diet.3 Similarly, a second Italian study found that celiac patients who had trouble conceiving were able to get pregnant as early as two months after starting a gluten-free diet.4 However, such findings need further confirmation as both of these studies involved only a few participants.
This recent US study suggests the need for growing awareness among physicians and patients that this autoimmune disorder can result in significant complications for women seeking to have children. When patients experience recurrent complications in pregnancy, the researchers suggest that physicians should consider undiagnosed celiac disease as a strong possible cause, and then screen them for the serologic markers.