At 18 weeks the mothers answered questionnaires concerning their profile, health, nutrition, vitamins, medications and stress. Household exposures were assessed using a home environment questionnaire.

Blood (whole blood, plasma, serum) was collected. If blood was not collected, a saliva sample was collected instead.

At 36 weeks the mothers answered a psychosocial questionnaire, collecting information about socioeconomic status, stress, depressive symptoms and social relationships. A mother life stress interview was also completed.

At the time of birth, the mothers answered a questionnaire concerning their medications.

At 3 months postpartum, mothers answered questionnaires concerning their profile/residence, nutrition, vitamins and supplements, and medications.

A breast milk sample was collected.

At 6 months postpartum, the mothers answered questionnaires concerning their medications and level of stress.

At 1 year postpartum, the mothers answered questionnaires concerning their profile/residence, health, nutrition, vitamins and supplements, medications and socio-economic status. Maternal psychosocial characteristics were assessed by self-report which included stress, depressive symptoms and social relationships. Parenting stress was also assessed, and a mother life stress interview (Vancouver only) was completed.

During this visit a skin prick and spirometry tests were performed.

If samples were not collected during the prenatal visit, a blood or saliva sample would be collected at this time.

At 1.5 years postpartum, the mothers answered a questionnaire concerning their level of stress.

At 2 years postpartum, the mothers answered questionnaires concerning their profile/residence, stress and parenting stress.

At 2.5 years postpartum, the mothers answered a questionnaire concerning their level of stress.

At 3 years postpartum, the mothers answered questionnaires concerning their profile/residence and socio-economic status. Maternal psychosocial characteristics were assessed by self-report which included stress, depressive symptoms and social relationships. Parenting stress was also assessed.

At 4 years postpartum, the mothers answered questionnaires concerning their profile/residence and socio-economic status. Maternal psychosocial characteristics were assessed by self-report which included stress, depressive symptoms and social relationships. Parenting stress was also assessed.

At 5 years postpartum, the mothers answered questionnaires concerning their profile/residence, health, nutrition, vitamins and supplements, medications and socio-economic status. Maternal psychosocial characteristics were assessed by self-report which included stress, depressive symptoms and social relationships. Parenting stress was also assessed.

At 8 years postpartum, the mothers answered questionnaires concerning their profile/residence, health, nutrition, vitamins and supplements, medications and socio-economic status. Maternal psychosocial characteristics were assessed by self-report which included stress, depressive symptoms and social relationships. Parenting stress was also assessed.

If samples were not collected at previous visits, blood and saliva would be collected at this time.

Information on profile/residence, health, nutrition and socio-economic status are collected. Maternal psychosocial characteristics are assessed by self-report which included stress, and parenting stress, physical activities, home environment and residence is also collected. Spirometry tests, blood pressure and body composition measures are taken for a subset of the population. If samples are not collected at previous visits, blood and saliva would be collected at this time. An allergy skin prick test is also performed.

At birth, the parents answered questionnaires concerning the child delivery and his medication intake.

A nitric oxide test was also performed.

During this visit a meconium/stool sample and cord blood sample (CBC, whole blood, whole blood RNA, plasma, mononuclear cells, mononuclear cells RNA, stimulated whole blood, serum) were collected.

Information about delivery was also extracted from the child's medical chart.

At 3 months postpartum, the parents answered questionnaires concerning the child's health, nutrition and diet, and medications. Household exposures were assessed using a home environment questionnaire and a home assessment by the interviewer.

Also, in Toronto only, a nitric oxide test and a pulmonary function test were done.

During this visit a urine, nasal swab and stool samples were collected. A dust sampling of the house for allergens and pollutants was performed as well.

At 6 months postpartum, the parents answered questionnaires concerning the child's health, nutrition and diet, and medications. Household exposures were assessed using a home environment questionnaire.

At 1 year postpartum, the parents answered questionnaires concerning the child's health, nutrition and diet, and medications. Household exposures were assessed using a home environment questionnaire. A food packaging and preparation questionnaire was also completed.

Clinical information was collected through a clinical assessment, which included questions from the International Study of Asthma and Allergies in Childhood (ISAAC) and also examination for evidence of atopic dermatitis, allergic rhinitis and asthma.

A skin prick test was done. In Toronto only, a nitric oxide and spirometry tests were completed as well.

During this visit a blood (CBC, whole blood, plasma, mononuclear cells, stimulated whole blood, serum, DNA), urine, nasal swab, and stool samples were collected. If blood was not collected, a saliva sample was collected instead.

At 1.5 years postpartum, the parents answered questionnaires concerning the child's health, nutrition and diet, and medications. Household exposures were assessed using a home environment questionnaire

In Toronto only, a nitric oxide and spirometry tests were completed as well.

Also in Toronto only, a urine sample was collected.

At 2 years postpartum, the parents answered questionnaires concerning the child's health, nutrition and diet, and medications. Household exposures were assessed using a home environment questionnaire

At 2.5 years postpartum, the parents answered questionnaires concerning the child's health, nutrition and diet, and medications. Household exposures were assessed using a home environment questionnaire.

At 3 years postpartum, the parents answered questionnaires concerning the child's health, nutrition and diet, and medications. Household exposures were assessed using a home environment questionnaire. A food packaging and preparation questionnaire was also completed.

Clinical information was collected through a clinical assessment, which included questions from the International Study of Asthma and Allergies in Childhood (ISAAC) and also examination for evidence of atopic dermatitis, allergic rhinitis and asthma. General anthropometrics were performed including blood pressure, waist circumference and skinfold thickness.

A skin prick test was done. In Toronto only, a spirometry test was done as well.

During this visit a urine sample was collected. Blood was collected in Winnipeg only.

At 4 years postpartum, the parents answered questionnaires concerning the child's health, nutrition and diet, and medications. Household exposures were assessed using a home environment questionnaire. A food packaging and preparation questionnaire was also completed.

At 5 years postpartum, the parents answered questionnaires concerning the child's health, nutrition and diet, and medications. Household exposures were assessed using a home environment questionnaire. A food packaging and preparation questionnaire was also completed.

Clinical information was collected through a clinical assessment, which included questions from the International Study of Asthma and Allergies in Childhood (ISAAC) and also examination for evidence of atopic dermatitis, allergic rhinitis and asthma. General anthropometrics were performed including blood pressure, waist circumference and skinfold thickness.

A skin prick, a nitric oxide and spirometry tests were also completed.

A blood sample (CBC, whole blood, plasma, mononuclear cells, mononuclear cells RNA, stimulated whole blood, serum, DNA) was collected. If blood was not collected, a saliva sample was collected instead.

At 8 years postpartum, the parents answered questionnaires concerning the child's health, nutrition and diet, medications, behavior, sleep and stress. Children completed questionnaires concerning physical activity, bullying, anxiety and impairment. Household exposures were assessed using a home environment questionnaire. A food packaging and preparation questionnaire was also completed.

A methacholine challenge and spirometry tests were performed as well.

A blood (CBC, whole blood, whole blood RNA, plasma, mononuclear cells, mononuclear cells RNA, stimulated whole blood, serum, DNA), urine, nasal swab, stool and teeth samples were collected. If blood was not collected, a saliva sample was collected instead.

Health, nutrition and diet, medications, behavior (child behaviour checklist), sleep and stress. Children complete questionnaires concerning physical activity, bullying, depression and anxiety (self-identified) and impairment. Household exposures are assessed using a home environment questionnaire. A food packaging and preparation questionnaire is also completed.

Information on smoking, vaping, alcohol and cannabis use, clinical assessment history, gender and child media and technology use is also collected. Child cognitive and academic abilities, body image and puberty staging are assessed.

Methacholine challenge and spirometry tests are performed.

Anthropometric measures, body composition, and blood pressure are taken. A Methacholine challenge test is done in Toronto and Manitoba sites only. Exhaled nitric oxide, multiple breath washout, and forced oscillation technique measures are taken in Toronto sites only. An allergy skin prick test is also performed. Blood, urine, nasal swab and stool are collected. If blood is not collected, a saliva sample is collected instead. Location, physical activities and nutrition information are also collected through GPS, actigraph and ASA24 application.

At 18 weeks gestation, fathers answered questionnaires concerning their health and socio-economic status. Information about medication and supplements was also collected.

A skin prick and a spirometry tests were completed.

A blood sample was collected (whole blood, plasma, serum). If blood was not collected, a saliva sample was collected instead.

At 1 year postpartum, fathers answered a questionnaire concerning their socio-economic status.

If samples were not collected during the prenatal visit, a blood (whole blood, plasma, serum) or saliva sample would be collected at this time.

At 5 years postpartum, fathers answered questionnaires concerning their health and socio-economic status.

At 8 years postpartum, fathers answered questionnaires concerning their health and acitivity habits. A clinical assessment was also completed.

If samples were not collected during the prenatal or first year visit, a blood (whole blood, plasma, serum) and saliva samples would be collected at this time.

Information is collected on socioeconomic status, eating habits, health, stress, and home environment. A spirometry test is performed. The body composition is also measured. Blood and saliva samples are collected. An allergy skin prick test is also performed.