Table 3

Crude and adjusted hazard rate ratios and 95% CIs for the association between ASD and assisted conception*

	All		Boys		Girls
	Crude	Adjusted^†	Crude	Adjusted^†	Crude	Adjusted^†
Assisted conception	1.25 (1.09 to 1.43)	1.13 (0.97 to 1.31)	1.18 (1.01 to 1.37)	1.07 (0.91 to 1.27)	1.55 (1.14 to 2.10)	1.32 (0.93 to 1.88)
IVF	1.18 (0.96 to 1.44)	1.04 (0.83 to 1.31)	1.15 (0.92 to 1.44)	1.02 (0.79 to 1.32)	1.23 (0.75 to 2.03)	1.02 (0.57 to 1.81)
OI	1.31 (1.10 to 1.56)	1.20 (0.99 to 1.44)	1.20 (0.99 to 1.47)	1.12 (0.91 to 1.38)	1.80 (1.24 to 2.61)	1.56 (1.03 to 2.36)

↵* Reference: natural conception.
↵† Adjusted for maternal age, educational level, parity, smoking, body weight and multiplicity.
ASD, autism spectrum disorders; IVF, in vitro fertilisation; OI, ovulation induction.