Table 3.

Incidence rate ratios for the effect of a cancer diagnosis on subsequent parity using conditional Poisson regression models, additionally adjusted for race and/or ethnicity and the number of live births before cancer diagnosis. Carcinoma in situ and their controls were excluded from this analysis.

Cancer types	All			18–30 y			31–40 y			≥41 y
	IRR	95% CI	P value	IRR	95% CI	P value	IRR	95% CI	P value	IRR	95% CI	P value
All cancers	0.69	0.67–0.70	<.001	0.72	0.69–0.75	<.001	0.61	0.57–0.64	<.001	0.45	0.40–0.49	<.001
Nongynecologic cancer
Breast	0.42	0.38–0.45	<.001	0.57	0.45–0.71	<.001	0.34	0.29–0.39	<.001	0.24	0.20–0.30	<.001
Hodgkin lymphoma	0.68	0.60–0.76	<.001	0.64	0.55–0.74	<.001	0.95	0.72–1.25	.707	-	-	<.001
Non-Hodgkin lymphoma	0.75	0.65–0.87	<.001	0.80	0.63–1.01	.059	0.54	0.38–0.78	<.001	1.71	1.20–2.43	.003
Leukemia	0.25	0.20–0.33	<.001	0.26	0.18–0.37	<.001	0.16	0.08–0.33	<.001	1.18	0.75–1.85	.475
GI cancers	0.41	0.28–0.60	<.001	0.45	0.20–1.01	.058	0.29	0.12–0.68	.005	-	-	.941
Soft tissue	0.57	0.44–0.73	<.001	0.59	0.41–0.85	.005	0.48	0.28–0.81	.006	-	-	-
Central nervous system cancers	0.53	0.47–0.59	<.001	0.55	0.46–0.66	<.001	0.46	0.36–0.59	<.001	-	-	.889
Gynecologic cancer
Vulva and vagina	0.72	0.54–0.96	.027	0.63	0.36–1.07	.091	2.08	1.02–4.27	.049	-	-	-
Cervix	0.30	0.25–0.35	<.001	0.36	0.27–0.49	<.001	0.22	0.17–0.30	<.001	0.26	0.14–0.47	<.001
Uterine corpus	0.18	0.13–0.24	<.001	0.31	0.15–0.65	.002	0.06	0.02–0.14	<.001	-	-	.908
Ovary	0.50	0.42–0.59	<.001	0.51	0.41–0.64	<.001	0.46	0.30–0.72	<.001	-	-	.917
Others	0.86	0.83–0.90	<.001	0.85	0.81–0.90	<.001	0.89	0.83–0.96	.004	0.66	0.57–0.76	<.001

Note: CI = confidence interval; GI = gastrointestinal; IRR = incidence rate ratio.