Table 5. Crude and adjusted odds ratios when comparing recurrent preterm with full-term newborns, after propensity score. Brazil, 2011–2012.

	Crude OR (95%CI)	OR after balancing (95%CI)
Recurrent prematurity
General
< 37 weeks	4.25 (3.62–4.97)	3.72 (3.01–4.61)
39–40 weeks	1.00
Spontaneous
< 37 weeks	4.10 (3.39–4.95)	3.89 (3.01–5.03)
39–40 weeks	1.00	1.00
Provider-initiated
< 37 weeks	4.48 (3.59–5.60)	3.47 (2.59–4.66)
39–40 weeks	1.00	1.00

OR: odds ratio; 95%CI: 95% confidence interval.