Table 4a:
Key maternal-related, harmonized characteristics from cohorts contributing to the current pooled dataset.
| ALSPAC | CCP | DNBC | JPS | MoBa | TIHS | |
|---|---|---|---|---|---|---|
| Full cohort population [Total =374,600] | 14,049 | 53, 679 | 94,690 | 90,079 | 111,399 | 10,624 |
| Recruitment years | 1990 – 1992 | 1959 – 1966 | 1996 – 2002 | 1964 – 1976 | 1999 – 2007 | 1988 – 1995 |
| Number of mother-child pairs with available data in pooled dataset [Total=189,326] | 14,042 * | 53,677 | 9,588 | 90,079 | 11,309 | 10,624 |
| Person-years of follow-up** [Total =2,880,400] | 112,341 | 350,027 | 756,848 | 720,169 | 856,096 | 84,928 |
| Age at time of index child’s birth, years; mean ± SD | 28.0 ± 5.0 | 24.1 ± 5.9 | 30.5 ± 4.3 | 27.7 ± 5.7 | 30.3 ± 4.6 | 24.3 ± 4.9 |
| Education: completed 12 or more years of education; % (n) | --- | 41 (21,700) | 65 (4,391) | 42 (37,423) | 80 (8,122) | 21 (2,177) |
| Married/cohabitating; % (n) | 70 (9,852) [married] | 77 (41,410) | 94 (8,285) | 99 (88,516) | 92 (10,259) | 80 (8492) |
| Height, cm; mean ± SD | 164.0 ± 6.7 | 160.9 ± 6.9 | 168.8 ± 6.0 | 161.9 ± 6.0 | 168.1 ±5.9 | 162.3 ±7.2 |
| Pre-pregnancy BMI, kg/m2; mean ± SD | 22.9 ± 3.8 | 22.7 ± 4.3 | 23.6 ± 4.4 | 22.1 ± 3.1 | 24.0 ± 4.2 | 23.3 ± 4.8 |
| Total pregnancy weight change, kg; mean ± SD | 12.5 ± 4.8 | 9.7 ± 5.1 | 15.0 ± 6.1 | 11.2 ± 4.4 | 15.0 ± 6.0 | 14.2 ± 6.7 |
| Any smoking during pregnancy; % (n) | 30 (3,670) | 46 (34,317) | 26 (2,413) | 12 (3,389) sub-cohort of 20,000 | 11 (973) | 51 (5,431) |
| Partner or person living in home smoked during pregnancy; % (n) | 46 (5,512) | --- | 66 (5,743) | 44 (7,253) | 9 (842) | 54 (5,722) |
| Any alcohol consumption during pregnancy; % (n) | 73 (9,083) | --- | 56 (5,287) | --- | 31 (2,793) | 34 (3,590) |
| Intake of vitamin supplement containing folic acid during pregnancy; % (n) | 23 (2,707) | --- | 79 (7,613) | --- | 80 (9,015) | 48 (5,035) |
| Diabetes: % (n) | --- | |||||
| - Any type | 0.9 (105) | 0.8 (404) | 2 (176) | 0.7 (627) | 1.3 (151) | |
| - Gestational | 0.5 (57) | 0.2 (127) | 2 (147) | 0.5 (455) | 0.8 (92) | |
| Previous miscarriage % (n) | 22 (2,812) | 18 (9,476) | 18 (1,753) | 20 (9,064) | 11 (1,216) | --- |
| Mother had x-ray of hip, pelvis, abdomen, or back area | 2 (210) | 20 (10,550) | --- | 0.1 (16) | 0.4 (44) | --- |
| Parity *** % (n) | ||||||
| 0 | 45 (5,763) | 4 (2,192) | 47 (4,271) | 29 (25,750) | 45 (5,099) | 45 (4749) |
| 1 | 35 (4,476) | 23 (12,161) | 36 (3,295) | 24 (21,605) | 36 (4,059) | 33 (3454) |
| 2 | 14 (1,818) | 16 (8,559) | 13 (1,196) | 17 (15,282) | 16 (1,753) | 15 (1595) |
| 3 | 4 (529) | 11 (5,909) | 3 (234) | 10 (9,124) | 3 (317) | 5 (541) |
| 4+ | 1.8 (227) | 19 (10,114) | 0.6 (55) | 20 (17,689) | 0.6 (71) | 3 (283) |
Numbers reported as % (n) for categorical variables and mean ± sd for continuous variables based on total number of data points available for each variable.
Difference between numbers in full ALSPAC cohort and data available for I4C is due to numbers in I4C not including triplets and quadruplets due to confidentiality reasons.
Person-years of follow-up is based on start time defined as birth date (date is set to zero years); end time for those with cancer defined as the date of cancer diagnosis; end time for those without cancer defined as the date the child is no longer under observation.
Parity defined as the number of previous pregnancies resulting in a live or stillbirth
“---“ indicates data was not collected for this particular cohort or are not reliable if collected, or not able to be harmonized with other cohorts.