The Ontario Birth Study (OBS) is a research platform developed by the Lunenfeld-Tanenbaum Research Institute and Mount Sinai Hospital (MSH) with support from Ontario Institute of Cancer Research (OICR) and the Fraser Mustard Institute for Human Development at the University of Toronto.

The Ontario Birth Study is an open longitudinal pregnancy cohort designed to serve as 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. 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.

See below for: Protocol | Lifestyle Questionnaires | Diet Questionnaire | The Biological Samples | The Clinical Data

Protocol

Pregnant women are approached by OBS staff at their first ultrasound or prenatal visit at Mount Sinai Hospital and St. Michael’s Hospital obstetrics clinics. Subjects are recruited based on the following criteria:

Inclusion criteria

Pregnant women less than 17 weeks gestational age
At least 18 years of age
English speaking
Delivering at an OBS Hospital
Antenatal care at an OBS Hospital

Exclusion criteria

Non-viable fetus
Unable to provide informed consent
Known significant abnormalities

The consent obtained from all women covers questionnaire data, biospecimens, ultrasounds, and access to clinical records. As outlined in table 1, OBS participants are asked to complete four questionnaires: three lifestyle questionnaires and the Canadian Diet History Questionnaire II*Web. The scheduled collection of biospecimens, including maternal blood, infant blood spot cards, and vaginal swabs, is also shown in the table.

Table 1. Ontario Birth Study Data Collection Timeline

Time of your routine visit	Blood work	Vaginal Swabs	Lifestyle Questionnaire	Diet Questionnaire	Approximate Time Commitment
Week 11-14	30-40 cc	2-4 swabs*	✔ (LSQ1)	-	45 min
Week 16	30-40 cc	-	-	✔	45 min
Week 28	30-40 cc	-	✔ (LSQ2)	-	30 min
Week 34-38	-	2 swabs	-	-	10 min
Delivery	30 cc; Infant blood spot card	-	-	-	10 min
6 weeks after Delivery	-	-	✔ (LSQ3)	-	30 min

*Women with a previous preterm delivery will be asked to provide 2 additional swabs (for a total of 4) at their first vaginal swab collection

Lifestyle Questionnaires

Women enrolled complete three lifestyle questionnaires using Research Electronic Data Capture (REDCap). Data collection fields are harmonized with the Better Outcomes Registry and Network (BORN). Some examples of the available data are provided below.

Table 2. Summary of maternal OBS survey instruments by timing of questionnaires

		Timing of Questions
Topic	Detailed items	12-16 wks GA	28-32 wks GA	6-10 wks Postpartum
Demographic info and family characteristics	Date of birth	X
	Marital status	X	X	X
	Details about Father	X
	Mother’s siblings	X
	Adopted	X
	Education	X
Anthropometry	Right/left handed	X
	Ability to stand	X
	Height	X
	Weight (current and usual)	X	X	X
	Weight loss and control	X	X
Health Status	Self-reported health	X	X	X
	Last check-up and dental	X
	Sexual orientation	X
	Sexual partners		X
	Bowel movement	X
Oral Health	Last dental visit, gum disease & dental problems during pregnancy		X
Menstrual History	Age at first period	X
Women’s health history	Contraceptive use	X
	Sexual activity	X
	Uterine fibroids or defect
Screening	Mammogram	X
	Pap smear, cervical biopsy	X	X
	Colorectal cancer screening
Current Pregnancy	Last menstrual period	X
	When did you know	X
	Feelings about pregnancy	X
	Intention to raise child	X
Fertility treatment	Drugs, procedures, cost, elapsed time	X
Health during pregnancy	Bleeding, nausea, swelling	X	X
	Fever & other infections		X
	Pregnancy conditions		X
	Progesterone		X
	X-rays, vaccines		X
	Hospitalization		X
	Bed rest		X
Previous Pregnancies	Mothers age, father, fertility treatments, multiples, pregnancy conditions, outcome, birthweight, gestational age, delivery type, child death, breastfeeding	X
Other children	Adopted, foster, other	X
Personal medical history	List of conditions from OHS (predominately chronic diseases and cancer)	X
Family health history	List of conditions for parents, siblings and previous children	X
Mother’s own birth	Birth weight, gestational age		X
Medication	Prescription and non-prescription	X	X
Vitamins, supplements	Before and during pregnancy	X	X	X
Vitamins, supplements	Fiber supplements	X	X
Smoking and tobacco products	Before pregnancy, during pregnancy, Other tobacco products	X	X	X
Smoking and tobacco products			X
Environmental tobacco exposure	Before and during pregnancy at home, work and social		X	X
Physical Activity	Vigorous and moderate activity before and during pregnancy;	X	X
Physical Activity	Sedentary activity	X	X
Sleep	Duration at night and day, disrupted breathing, snoring	X		X
Sleep	Infant sleep			X
Sunlight & skin type	Skin response to sun	X
Sunlight & skin type	Sunbed use	X	X
Alcohol	Before and during pregnancy, type of alcohol, binge drinking	X	X	X
Food intake	Vegetables, fruit, juice	X
	Food insecurity		X
	Dietary restrictions		X
Emotional Health	Depression (DHQ-2 item)	X	X	X
	Anxiety (GAD-2 item)	X	X	X
	Depression (EPDS)		X	X
	Anxiety (STAI-SF)		X	X
	Perceived stress (4-item)	X	X	X
	Attachment (Bartholomew Horowitz)		X	X
	Intimate partner violence (WAST)		X
	Adverse Childhood Experiences (ACE)			X
	Childbearing Attitudes	X	X	X
	Pregnancy Experiences Scale		X
Background	Ethnicity and Country	X
Work	Work status, Job description	X	X	X
Occupational exposures	Shift work	X	X
Occupational exposures	Chemical exposures		X
Residence	Length of time lived there	X
Income	Household income	X
	Number of people in home	X	X	X
	Number of rooms	X	X
	Owning house and car		X
Environmental exposures	Pets, pesticides, proximity to farm, busy roads, chemical dump		X
Questions about the baby’s biologic father	Age, siblings/twin, adopted, education, height, weight, alcohol, smoking, ethnicity, left/right handed, restricted diet, sexual partners & infections		X
Other Questions	Permission to contact family members (mothers and baby’s father)	X	X
Other Questions	Name of pediatrician or family doctor	X	X
Labour and delivery	Type of delivery, hospitalization			X
Infant Health	Medication use			X
	Circumcision			X
	Jaundice			X
	Hospitalization			X
	General health			X
Infant feeding	Intention to breastfeed		X
	Breastfeeding			X
	Formula type			X
	Vitamin use			X
Crying	Crying Patterns Questionnaire			X

Diet Questionnaire

The web-based Canadian Diet History Questionnaire II*Web queries the participant’s diet over the past month. The questionnaire asks questions about Canadian-specific types, brands, and proportions of food. Based on questionnaire answers, the daily nutrient intake (e.g., total fat, total calorie intake, other vitamins and minerals) is then calculated.

The Biological Samples

Biospecimens are collected and processed at the Mount Sinai Hospital’s Biospecimen Repository and Processing Lab. Collection of placentas is done through the Mount Sinai Hospital’s Biobank. The collection of biological samples includes:

Maternal Blood

maternal DNA
leukocytes
plasma
serum

Infant Blood Spot Cards

infant DNA

Vaginal Swabs

bacterial DNA
cytokines

The Clinical Data

Additional data collected from the antenatal records and hospital medical charts are abstracted and entered into Medidata RAVE, an electronic data capture and storage platform, housed at the Applied Health Research Centre. Some of the available data includes:

Routine Demographic

age
height
weight

Medical History and Pregnancy Obstetrical History

medications
gravidity
parity

Current Pregnancy

blood pressure
blood work
urine test
ultrasound reports
interventions
labour details

Infant Assessment

gestational age
birth weight
gender

For Researchers