Infertility and celiac disease: Is there a connection?

If changing your diet could help you get pregnant, would you do it? Of course you would—if only it were that simple.

For Shannon Gibson, it was. She struggled with unexplained infertility for 18 months when she was tested for celiac disease following her father’s diagnosis of the autoimmune disease. The results were positive. Gibson, who lives in Ripples, New Brunswick, immediately began to treat the condition by removing gluten—a protein found primarily in wheat, rye and barley—from her diet. Within a year, she was pregnant.

Coincidence? It’s possible. But Gibson’s story isn’t uncommon. Anecdotally, doctors say they frequently see a link between untreated celiac disease and unexplained infertility. The science behind the connection is still developing: One study published earlier this year in the Journal of Clinical Gastroenterology found that the prevalence of celiac disease among American women with unexplained infertility was an astounding six times higher than that of a control group, though other studies have found no increased prevalence at all.

However, researchers generally agree that, although it’s not fully understood, there is a connection between celiac disease and infertility. That means that for some women, a simple, inexpensive blood test for the increasingly common, frequently undiagnosed condition could change their lives forever.

What is celiac disease?

Celiac disease is an autoimmune condition in which the lining of the small intestine is damaged by gluten. That damage is bad news because the small intestine has a very important job: absorbing nutrients from food. In the long term, untreated celiac disease can cause iron deficiency, osteoporosis and cancer.

The effects of untreated celiac disease can vary widely from person to person. Sufferers can experience some, all or even none of the disease’s long list of seemingly disparate symptoms, which may include bowel problems (diarrhea, constipation, stomach aches, bloating), weight loss, rashes, fatigue and anemia. The disease can be difficult to diagnose because its symptoms can be confused with those of other disorders. Some studies suggest that reproductive disorders may be the first symptom of celiac disease in otherwise-asymptomatic women.

How common is celiac disease?

The Canadian Celiac Association estimates that celiac disease affects one in every 133 Canadians, though many of them remain undiagnosed. Health Canada says the condition is one of the most common chronic diseases in the world, and it’s becoming more common. “In adults, there’s some data to show that there is a true increase in the incidence and prevalence of celiac disease,” says Mohsin Rashid, a Halifax-based paediatric gastroenterologist. “The incidence is doubling every 15 to 20 years in the U.S.”

How can celiac disease affect fertility?

The mechanisms for how untreated celiac disease could affect fertility aren’t well understood. But there are many reasonable theories, says Ellen Greenblatt, clinical director of Mount Sinai Fertility in Toronto. For example, when someone has untreated celiac disease, they may be nutrient deficient and have a systemic chronic inflammatory process going on that affects reproduction at many levels, she says. Inflammation, she explains, could theoretically affect egg quality or the ability of the endometrium to allow an egg to implant. “We see that in other chronic illnesses,” she says.

In 2011, Kristen Sanger had felt unwell for more than a year. She was underweight, fatigued and weak, and a blood test showed that she was severely lacking in vitamins, nutrients and iron. But doctors were stumped. Before her wedding in September 2011, she asked her doctor about getting pregnant. “He said that I probably wasn’t healthy enough to carry a baby,” she recalls. After the wedding, Sanger and her partner, who live in Toronto, “pulled the goalie,” just to see. Fourteen months later, still ill and not yet pregnant, she met with a gastroenterologist to look into a possible bleeding ulcer and discovered that she had celiac disease.

Sanger immediately began a gluten-free diet, along with six rounds of intravenous iron infusions and regular B12 shots. “In about six to eight months, I began to feel like I had energy again,” she says. “After about a year, I felt like I had before.” A year after that, Sanger got pregnant, and she is currently in her seventh month of a normal, healthy pregnancy.

“There’s definitely a lack of concrete evidence to connect celiac disease with infertility,” says Sanger, who delved deeply into the medical research throughout her ordeal, “but my doctor was pretty blunt about how much my fertility could be affected by the damage in my body.”

How common is it for celiac disease to affect fertility?

Why don’t fertility clinics test for celiac disease? Would it help enough people to be cost effective?

In 2009, Greenblatt launched her own study to find out. To her great surprise, she found no increased incidence of celiac disease among patients with unexplained infertility. That said, Greenblatt still believes that celiac disease can affect a woman’s chances of getting and staying pregnant and will sometimes screen for the disease in her patients. “If someone has it in her family or has symptoms that look like irritable bowel syndrome, I might throw in the test,” she says. But she doesn’t feel that all women with unexplained infertility warrant a screening for celiac disease based on her results—at least not from a Toronto demographic.

Other research has been far more conclusive. Of close to 2,000 women who took part in the Canadian Celiac Health Survey—the findings of which were published in 2007—almost 15 percent said they had difficulty conceiving and 31 percent had experienced miscarriages. A 2014 meta-review of research on celiac disease and reproductive disorders, published online in the medical journal Human Reproduction Update, found that patients with unexplained infertility, recurrent miscarriages or intrauterine growth restriction had a “significantly higher risk” of celiac disease. They concluded that physicians should investigate women with any of these conditions for undiagnosed celiac disease.

Testing for celiac disease is as simple as asking your general practitioner for a blood test. You can even skip the lab completely and hit the drugstore. Some pharmacies carry an at-home celiac test, like Glutenpro’s CeliacSure, which is 93.5 percent accurate and costs about $59. If you’re considering going gluten-free, take the test first because once you’re on a gluten-free diet, testing for celiac disease is likely to result in a false negative.

For Gibson, a positive diagnosis seemed to be the key to conceiving and carrying a baby to full term. In fact, she is now a mom of three. “I think all fertility clinics should do the test,” she says. “They do blood work anyway, so it wouldn’t be much more work to look for celiac disease. It would be worthwhile.”

Read more: Can you boost your fertility?
What you need to know about getting pregnant in your 20s, 30s and 40s
The leading causes of infertility