Table 3.

Number of meningioma tumors diagnosed during pregnancy and number of years since last delivery by delivery number.

Yeara	No. of cases according to number of previous deliveries				Total	Incidence rate ratioc
	1	2	3	4+		Unadjusted			Adjustedd
						IRR	95% CI		IRR	95% CI
0b	2	4	5	0	11	0.12	0.07	0.22	0.40	0.22	0.73
1	11	15	9	5	40	0.35	0.25	0.48	1.10	0.79	1.54
2	12	16	7	5	40	0.44	0.32	0.61	1.12	0.81	1.56
3	7	13	9	3	32	0.46	0.32	0.65	0.93	0.65	1.33
4	6	14	6	2	28	0.49	0.33	0.71	0.81	0.56	1.19
5	12	16	8	2	38	0.77	0.56	1.07	1.11	0.80	1.54
6	5	13	8	2	28	0.63	0.43	0.92	0.78	0.53	1.14
7	5	22	8	3	38	0.96	0.69	1.32	1.05	0.76	1.46
8	7	21	6	4	38	1.04	0.75	1.44	1.02	0.73	1.41
9	4	16	12	3	35	1.04	0.74	1.46	0.91	0.65	1.28
10	8	16	10	3	37	1.19	0.86	1.65	0.95	0.68	1.32
11	7	19	8	2	36	1.24	0.89	1.74	0.91	0.65	1.28
12	4	23	5	1	33	1.22	0.86	1.73	0.83	0.59	1.18
13	5	17	7	1	30	1.19	0.83	1.72	0.75	0.52	1.08
14	7	24	11	2	44	1.91	1.41	2.59	1.13	0.84	1.54
15	6	18	11	2	37	1.72	1.24	2.39	0.96	0.69	1.33
16	5	30	9	3	47	2.38	1.78	3.20	1.26	0.94	1.70
17	8	18	13	2	41	2.24	1.64	3.06	1.13	0.82	1.55
18	6	25	10	3	44	2.62	1.94	3.55	1.27	0.93	1.72
19	7	12	8	1	28	1.79	1.23	2.61	0.83	0.57	1.21
20	9	21	6	1	37	2.66	1.91	3.69	1.19	0.85	1.67
21+	41	89	28	9	167	3.00	2.53	3.55	1.21	0.97	1.50
Total	184	462	204	59	909	–	–	–	–	–	–

Unadjusted and adjusted incidence rate ratio (IRR) with 95% confidence intervals by number of years since last delivery.

Women with at least one delivery during the follow-up period 1973–2015.

–, Not applicable.

^aNumber of years since last delivery.

^bTime during pregnancy.

^cIncidence rate ratio for number of years since last delivery versus all other years.

^dAdjusted for attained age.