About OBS

Pregnancy and early childhood represent critical developmental epochs that impact health throughout our lives. Globally 536,000 women die of pregnancy-related causes each year, and about 10 million suffer complications related to pregnancy or childbirth. Over 13 million babies are born prematurely and 3 million are stillborn annually. Despite decades of research our ability to predict or prevent these conditions is poor. Furthermore, it is now clear that a baby’s development impacts its life-long health. Suboptimal growth and development of the baby during pregnancy and early childhood contributes a major risk factor for the development of adult diseases such as the metabolic syndrome (obesity, hypertension and abnormal lipids); Type II diabetes; cardiovascular disease; and mental illness. It is thus clear that the environment of mother, baby and child is a key contributor to diseases and conditions that account for approximately one third of the global burden of disease. There is a recognized need for large long-term prospective studies to evaluate maternal and infant health outcomes and early life determinants of health and disease. The Ontario Birth Study (OBS) is a prospective cohort study with ongoing recruitment developed to address this need.

The overall aim of the Ontario Birth Study is to develop a platform for research on pregnancy complications, maternal and infant health, and, ultimately, to assemble a cohort for future studies on the developmental origins of health and disease. As a platform for research, one of the goals of the OBS is to streamline research, reducing the burden of research on both clinical care and patients while increasing research opportunities (lower cost, increased feasibility and data availability) and enhancing clinical care. Ultimately the goal of the OBS is to offer all women seeking antenatal care at Mount Sinai Hospital (MSH) and St. Michael’s Hospital the opportunity to participate in an ongoing investigation of pregnancy health and the gene-environment interactions that establish developmental trajectories to health, learning and social functioning.