Maternal celiac disease, undiagnosed at the time of delivery, is a risk factor for adverse fetal outcomes, but celiac disease diagnosed before giving birth is not associated with such outcomes, results from a large Swedish population study suggest.
“Our results underline the importance of screening for CD [celiac disease] among women of reproductive age, because some 1% of young people may have CD, and treatment seems to reduce dramatically the rate of complications in pregnancy,” reported the investigators, led by Jonas F. Ludvigsson, M.D., of the pediatric department at Örebro University Hospital, Sweden.
Celiac disease is a chronic intestinal malabsorption disorder caused by intolerance to gluten. Diagnosis is suspected on the basis of symptoms, enhanced by laboratory and x-ray studies, and confirmed by biopsy. A gluten-free diet is the only treatment.
Using a national medical registry, Ludvigsson and his associates identified 2,078 women aged 15–44 with a diagnosis of CD who gave birth to singleton live-born infants between 1973 and 2001. A total of 1,149 women were diagnosed with CD before giving birth, and 929 were diagnosed after giving birth (Gastroenterology 2005;129:454–63).
After adjusting for potential confounding factors such as smoking, age, parity, and diabetes mellitus, the subjects diagnosed with CD after birth were associated with an increased risk of intrauterine growth retardation (odds ratio of 1.62), preterm birth (OR 1.71), cesarean section (OR 1.82), low birth weight (OR 2.13), and very low birth weight (OR 2.45). Subjects diagnosed with CD before the birth of their offspring were not significantly associated with a higher risk of these outcomes.
The risk for nearly all adverse outcomes was highest in women who received a diagnosis of CD within 5 years after childbirth.
They postulated that insufficient fetal nutrition causes the increased risk of intrauterine growth retardation and low birth weight seen in offspring of women diagnosed after giving birth. “It has previously been shown that undiagnosed adult patients with CD have lower serum ferritin, vitamin B12, and erythrocyte folate,” the investigators wrote. “A second explanation for the IUGR [intrauterine growth retardation] and low birth weight could be CD-mediated inflammation or dysregulation of the immune system. The latter explanation is particularly attractive when trying to explain the shorter pregnancy duration seen in offspring to patients with undiagnosed celiac disease.”
A limitation of the study, the authors acknowledged, is the risk of low sensitivity. “Not all patients with CD are admitted to a hospital, and our unexposed women certainly include several false-negative patients,” they said. “This is, however, unlikely to affect our risk estimates because the number of cases is large, and healthy women without CD vastly outnumber false-negative cases, now classified as unexposed.”