The Impact of Oral Intake of Dydrogesterone on Fetal Heart Development During Early Pregnancy.

Congenital heart disease is the most frequent form of congenital anomaly in newborn infants and accounts for more than a quarter of all serious congenital afflictions worldwide. A genetic etiology is identified in <20 % of cases of congenital heart defects, and in most cases the etiology remains a mystery. In the context of the health burden caused by congenital heart disease, the contribution of non-inherited risk factors is important especially if it turns out to be caused by a drug which can be avoided during pregnancy. We sought to determine whether maternal dydrogesterone treatment in early pregnancy is associated with congenital heart disease in the infant. We conducted a retrospective case-control study of birth defects and associated risk factors. Data were obtained and compared between 202 children born with congenital heart disease and a control group consisting of 200 children. All children were born in the period of 2010-2013. Dydrogesterone exposure was defined as any reported use during the first trimester of pregnancy. Exclusion criteria included stillbirths, children with chromosomal abnormalities and infants of mothers with chronic medical illnesses, e.g., diabetes. Binary logistic regression analyses were used to analyze the data and attempt to identify a causal relationship between drug exposure and congenital heart disease. Mothers of children born with congenital heart disease received more dydrogesterone during first trimester of pregnancy than mothers of children in the control group [adjusted odds ratio 2.71; (95 % CI 1.54-4.24); P = 0.001]. We identified a positive association between dydrogesterone usage during early pregnancy and congenital heart disease in the offspring. Nevertheless, further studies are needed to confirm these results.