Table 3.

Interaction between age and desire for additional children in relation to pregnancy incidence

Age	Desire additional children	n (%)	Pregnancy ratea	HR	95% CI
Age ≥ 30 years	No	133 (29.8)	3.2	1	Reference
Age < 30 years	No	109 (24.4)	6.4	1.98	(0.70–5.56)
Age ≥ 30 years	Yes	62 (13.9)	8.8	2.69	(0.91–8.02)
Age < 30 years	Yes	142 (31.8)	22.9	6.94	(2.91–16.55)

Hazard ratios (HR) are based on a Cox proportional hazards regression model with categories for all combinations of age (<30 vs. ≥30) and self-reported desire for additional children at enrollment

Numbers in bold face indicate p < 0.05

^aPer 100 woman-years