By Amy Ratner, Medical and Science News Analyst

Two weeks before her second baby was due in 1990, Alice Bast delivered a full-term stillbirth, a daughter who was named Emily. Bast, who had celiac disease but did not yet know it, then suffered multiple miscarriages before delivering her youngest daughter who weighed only two pounds.

Bast’s experience reflects the results of a new study from Denmarkthat finds women with undiagnosed celiac disease have a greater chance of having stillbirths, miscarriages and other pregnancy complications compared to both women who have been diagnosed and the general population.

But once a woman is diagnosed and goes on the gluten-free diet, she is at no more risk of reproductive problems than women in general, the study found.

Diagnosis critical

“Of all the consequences of undiagnosed celiac disease, the stillbirth of a child or a miscarriage is particularly devastating. Sadly, I know from personal experience,” said Bast, founder and CEO of Beyond Celiac. Bast’s first daughter was born healthy after an uncomplicated pregnancy. But between then and Bast’s second pregnancy, the symptoms of her as-yet undiagnosed celiac disease started to develop, and everything changed.

“That’s why getting out the word about a study like this, especially to young women and their doctors is so important,” she said. “And that is exactly why I started Beyond Celiac. I didn’t want anyone to have to suffer what I suffered.”

RELATED: Alice’s personal story

The study, published in the journal, Human Reproduction, shows how critical it is for physicians to consider undiagnosed celiac disease when a woman has reproductive problems, said Louise Grode, Ph.D., lead study author and a researcher at Horsens Regional Hospital. Results also highlight the need for early diagnosis of celiac disease in relationship to pregnancy.

At the same time, it’s comforting for women diagnosed with celiac disease to know they don’t seem to be any different than other women when it comes to pregnancy, Grode said. She noted that following the gluten-free diet is essential for women with celiac disease who want to become or are pregnant.

Celiac disease occurs in about one percent of the general population, but about 80 percent remain undiagnosed despite growing awareness and the availability of a blood test and biopsy to determine whether someone has the serious autoimmune condition.

Thousands of women studied

Grode and colleagues compared the medical records of 6,319 women identified as having celiac disease through the Danish National Patient Register to the records of 63,166 women who did not have the condition. The researchers from Horsens and Odense hospitals and Aarhus University looked at the chance and timing of pregnancy, live and stillbirths, molar and ectopic pregnancy and miscarriages.

The study found that when women with celiac disease were undiagnosed, they had 11 more miscarriages per 1,000 pregnancies and 1.62 more stillbirths per 1,000 pregnancies. In the two years prior to celiac disease diagnosis, women also become pregnant less often, with 25 fewer pregnancies per 1,000. The overall risk of pregnancy problems in undiagnosed women was 15 more per 1,000 pregnancies compared to women who did not have celiac disease.

Bast is often approached by women who were not able to have children and were later diagnosed with celiac disease. “So many women have come up to tell me their reproductive health stories,” she said. “So many women have spent years trying to get pregnant not knowing that they in fact had undiagnosed celiac disease and all they needed was a blood test.”

Take Action: If you have infertility or pregnancy complications, share our symptoms checklist with your doctor

Pregnancy complications in undiagnosed celiac disease have been linked in other studies to vitamin and mineral deficiencies that can occur when the absorbing lining of the intestine is damaged through exposure to gluten. The Danish researchers note that their results support this theory. Additionally, tissue transglutaminase (tTG) antibodies produced in response to celiac disease are thought to have an impact on implantation and survival of a pregnancy, according to the study.

Proactive testing needed

“This population-based study underscores the profound impact of undiagnosed celiac disease on women and families. In many patients the effects of celiac disease extend throughout the body, manifesting with symptoms that are usually not associated with an intestinal disorder,” said Marie Robert, Beyond Celiac chief scientific officer. “This new information highlights the need for better screening for celiac disease in young adults and illustrates the importance of ongoing research to understand mechanisms and discover treatments and a cure for celiac disease.”

Daniel Leffler, M.D., director of clinical research at the Celiac Center at Beth Israel Deaconess Medical Center who was not involved with the Danish study, noted there has been confusion and conflicting results in research related to celiac disease and pregnancy.

“I think this study substantiates the majority of data suggesting that uncontrolled celiac disease has an adverse effect on childbearing,” he said. “While these are admittedly small effects requiring thousands of patients to assess, they are real and provide a very good reason to be proactive about testing for celiac disease in young women.” At the 2017 Beyond Celiac Research Symposium, Leffler called for routine celiac disease testing for all women who have unexplained infertility.

“The message to women in general is that it is worth discussing celiac disease with your doctor if you have experienced fertility problems and adverse pregnancy outcomes,” Grode said.