A recent study published in the Canadian Medical Association Journal (CMAJ) reveals that hypertensive disorders of pregnancy (HDP) are becoming more common in Canada, even though the severe complications related to these conditions are decreasing. Experts emphasize the need for improved monitoring and better access to obstetric care.
The study analyzed data from nearly three million hospital births across Canada from 2012 to 2021. It found a 2.4% increase in the incidence of HDPs during this period. Despite this, the rates of serious complications such as early preterm delivery, intrauterine fetal death, and severe maternal morbidity have been declining.
HDPs, which include chronic hypertension, gestational hypertension, and preeclampsia or eclampsia, affect 5%-10% of pregnancies worldwide. They result in over 50,000 maternal deaths and 500,000 fetal and infant deaths annually.
Joel G. Ray, MD, a senior author of the study and obstetrical medicine specialist at St. Michael’s Hospital in Toronto, explained, “We lacked current data on hypertension in pregnancy and its impact on mothers and their babies, which led us to conduct this study.”
The research, which excluded data from Quebec, found that the overall rate of HDPs increased from 6.1% to 8.5% between 2012 and 2021. Specifically, preeclampsia rates rose from 1.6% to 2.6%. Additionally, the rate of Cesarean deliveries among women with HDP increased from 42.0% to 44.3% over the same period.
The study also highlighted demographic differences, noting higher rates of HDP among women under 20 and those over 34. Rates varied across provinces, with the Northwest Territories (6.5%) and Ontario (6.9%) having the lowest rates, while Newfoundland and Labrador had the highest at 10.7%.
Ray advocates for better management of pregnancy-related hypertension through effective medications and clearer communication with women about the importance of low-dose aspirin to prevent preeclampsia. He also suggests creating a handout for new mothers outlining preeclampsia symptoms and advising them to monitor their blood pressure shortly after discharge.
In a related editorial, Catherine Varner, MD, an emergency physician in Toronto and deputy editor of CMAJ, stressed the need for specialized obstetrical care for the growing number of high-risk pregnancies. She pointed out that Canada sees more emergency department visits in the early postpartum period compared to other countries, many of which could be handled in outpatient settings.
Varner noted that many new mothers visit emergency departments because they lack access to family doctors or obstetricians for follow-up care. She suggested that incorporating midwives into care teams could address some of these gaps, providing timely support both during and after pregnancy.
“Team-based care is essential as we do not have enough high-risk obstetrical providers to meet current needs,” Varner said.
