Table 2. Association between maternal fever and risk of ASD in offspring, at any time during pregnancy and by trimester.
| Exposure period | ASD fever-exposed N (%) | Non-case fever-exposed N (%) |
Crude model |
Adjusted model |
||||||
|---|---|---|---|---|---|---|---|---|---|---|
| OR | 95% CI | P-value | aORa | 95% CI | P-value | |||||
| Any time during pregnancyb (N=79 109) | 98 (20.68) | 13 509 (17.18) | 1.26 | 1.01 | 1.57 | 0.045 | 1.34 | 1.07 | 1.67 | 0.011 |
| First trimesterc (N=95 115) | 24 (4.14) | 3069 (3.25) | 1.29 | 0.85 | 1.94 | 0.229 | 1.34 | 0.89 | 2.02 | 0.162 |
| Second trimesterd (N=87 648) | 85 (16.04) | 11 067 (12.70) | 1.31 | 1.04 | 1.66 | 0.022 | 1.40 | 1.11 | 1.77 | 0.005 |
| Third trimestere (N=79 748) | 17 (3.56) | 2627 (3.31) | 1.08 | 0.66 | 1.75 | 0.761 | 1.15 | 0.70 | 1.87 | 0.583 |
Abbreviations: aOR, adjusted odds ratio; ASD, autism spectrum disorder; CI, confidence interval; OR, odds ratio.
Key: bold text represents significant findings, P<0.05.
a
Adjusted for: maternal age, smoking and parity; parental education and birth year.
b
Respondents to all three questionnaires containing prenatal fever data: ASD, N=474; non-case, N=78 635.
c
All respondents to 17-week prenatal questionnaire: ASD, N=580; non-case, N=94 535.
d
All respondents to both the 17- and 30-week prenatal questionnaires: ASD, N=530; non-case, N=87 118.
e
All respondents to both the 30-week prenatal and the 6-month postnatal questionnaires: ASD, N=477; non-case, N=79 271.