Crude hazard rate ratios (HRRs) and 95% CIs for the association between ASD and IVF according to specific underlying cause of infertility
| ASD | |||
| Underlying factor | Numbers exposed | Numbers exposed | Crude HRR |
| Natural conception | 555 828 | 3.394 (0.61%) | Reference |
| Mixed or unspecific factors | 5136 | 39 (0.76%) | 1.49 (1.08 to 2.04) |
| Tubal factor | 4859 | 26 (0.54%) | 0.86 (0.59 to 1.27) |
| Ovulation factor | 929 | 7 (0.75%) | 1.63 (0.78 to 3.42) |
| Male factor | 4019 | 23 (0.57%) | 1.18 (0.79 to 1.78) |
Percentages within categories are given.
ASD, autism spectrum disorders; IVF, in vitro fertilisation.