Table 2. Relative risk of ASD and two-sided 95% CIs for gestational age (week) versus week 40.

Week	Relative Risk (95% CI)	Relative Risk (95% CI)
22	-------	2.31 (2.15–2.48)
23	2.72 (1.84–4.02)
24	4.15 (3.24–5.33)
25	3.85 (3.11–4.76)
26	2.88 (2.28–3.64)
27	2.66 (2.14–3.30)
28	2.61 (2.13–3.19)
29	2.07 (1.68–2.54)
30	2.27 (1.91–2.70)
31	1.90 (1.61–2.24)
32	1.67 (1.44–1.93)	1.35 (1.30–1.40)
33	1.56 (1.38–1.76)
34	1.44 (1.31–1.59)
35	1.39 (1.28–1.50)
36	1.42 (1.34–1.50)
37	1.28 (1.23–1.33)	1.00
38	1.15 (1.12–1.18)
39	1.03 (1.00–1.05)
40	1.00
41	1.06 (1.03–1.09)
42	1.18 (1.14–1.22)
43	1.43 (1.26–1.62)	1.37 (1.21–1.54)
44	2.20 (1.43–3.37)

Relative risks estimated by log-binomial regression adjusted for country (Finland, Sweden, Norway), birth year (1995–1999, 2000–2004, 2005–2009, and 2010–2020), and maternal age (<20, 20–24, 25–29, 30–34, 35–39, and ≥40 years).

Abbreviation: CI, confidence interval.