CHIPS (control of hypertension in pregnancy study): a pilot trial

Almost 10 per cent of women who become pregnant develop hypertension (high blood pressure). Experts agree that pregnant women with severe hypertension should receive blood pressure medication to protect them from stroke. However, it is not clear if or how much the medication would benefit pregnant women with mild to moderate hypertension. A complicating factor is that the medication may also contribute to poorer growth and lower birth weight in babies, placing them at increased risk for health problems as newborns, children and adults. According to a national survey, Canadian obstetricians are unsure about prescribing blood pressure medication to women with mild to moderate hypertension. To help clarify the issue, Dr. Laura Magee and her research team have designed a Control of Hypertension in Pregnancy Study (CHIPS), aimed at determining if it is better for the baby (i.e. better growth before birth and better health thereafter) to allow a mother’s blood pressure to be higher than normal during pregnancy or to prescribe blood pressure medication to lower it. To begin, Dr. Magee is conducting a pilot trial to assess whether or not physicians would adhere to the treatment protocols in a full trial and to confirm if sufficient patients could be enrolled. If the pilot study indicates that CHIPS is feasible, the full trial will be conducted at major maternity centres across Canada.