Table 2.

Univariate conditional logistic regression analysis of delivery procedures, n = 342 or 171 pairs.

Category	Non-ASD n (%)	ASD n (%)	OR (95% CI)	p value
Vaginal	125 (56.3)	97 (43.7)	1	Reference
Vacuum/forceps	10 (45.4)	12 (54.5)	1.33 (0.57–3.12)	0.512
Cesarean, first-time	24 (33.3)	48 (66.6)	2.56 (1.44–4.58)	0.001
Cesarean, first-time no fetal indications	14 (29.8)	33 (70.2)	3.94 (1.54–10.09)	0.004
Cesarean, first-time fetal indications	10 (40.0)	15 (60.0)	1.18 (0.39–3.51)	0.769
Cesarean, repeata	12 (46.1)	14 (53.9)	1.55 (0.69–3.49)	0.284

ASD: autism spectrum disorder; OR: odds ratio, CI: confidence interval.

^aThe totals for repeat Cesarean (C/S) deliveries differ in Tables 1 and 2 for the reason that in Table 1 if the primary indication for delivery was not a scheduled, repeat C/S, the case would be categorized under one of the other primary indications.