The Ottawa and Kingston (OaK) Birth Cohort: development and achievements

The Ottawa and Kingston (OaK) Birth Cohort collected data on maternal and infant genetic and epidemiologic variables in order to (1) explore the association between folate supplementation or thrombophilias and adverse, placenta-mediated pregnancy outcomes; (2) create a biobank of maternal and infant biological and genetic samples; and (3) stimulate future research using this cohort data.

A prospective cohort design was used to collect mother and infant data. Women were recruited at 12 to 20 weeks' gestation, during prenatal care visits at The Ottawa Hospital and Kingston General Hospital from October 2002 to April 2009. Data on maternal and infant demographics, maternal health, obstetrical history, and pregnancy outcomes were collected. Testing was done for biological/serological markers associated with adverse pregnancy outcomes. Maternal and cord blood samples were biobanked.

A total of 8085 mothers were recruited to the OaK Birth Cohort. Analysis of the cohort data showed that taking multivitamin supplements containing folic acid was associated with a reduced risk of preeclampsia (aOR 0.37; 95% CI 0.18 to 0.75). The majority of participants agreed to have their genetic/biological samples biobanked (samples collected for n = 7241 mothers, n = 2175 infants) and to be re-contacted regarding future research opportunities.

Birth cohorts are a useful tool in determining associations between risk factors and adverse maternal and fetal outcomes, and can serve as a repository of data for future research. Creating strong research partnerships helped enhance financial resources and increase participant recruitment potential. Epidemiological and biobanked data and samples from the OaK Birth Cohort are available for use by other investigators.