Comparing the risk of asthma at 7 years among children conceived by assisted reproductive technologies with children of parents who tried to become pregnant for 12 months or were previously treated for unwanted childlessness in the MoBa
| Exposure | N | N cases (%) | Unadjusted RR (95% CI) | Adjusted* RR (95% CI) |
| Previously treated for unwanted childlessness | 4653 | 244 (5.2) | 1 | 1 |
| Conceived by assisted reproductive technologies | 1391 | 85 (6.1) | 1.17 (0. 92 to 1.48) | 1.23 (0.95 to 1.58) |
| Time to conception >12 months | 4964 | 262 (5.3) | 1 | 1 |
| Conceived by assisted reproductive technologies | 1391 | 85 (6.1) | 1.16 (0.91 to 1.47) | 1.22 (0.95 to 1.57) |
*Adjusted for maternal age, parity, education, smoking during pregnancy, prepregnancy BMI and maternal current asthma.
BMI, body mass index; MoBa, Norwegian Mother and Child Cohort Study; RR, relative risk.