Table 4.

Odds ratios (ORs)^a for thyroid cancer risk in offspring in relation to maternal, paternal, and birth characteristics and maternal and neonatal medical conditions, by histologic type and stage at diagnosis

	Papillary (n=1,967)		Follicular (n=281)		Localized (n=869)		Regional/distant (n=842)
	OR	95% CI	OR	95% CI	OR	95% CI	OR	95% CI
Maternal characteristics
Age at birth (per year)	1·00	0·99-1·00	0·98	0·95-1·00	1·00	0·99-1·02	1·00	0·98-1·01
Smoking during pregnancy (yes vs. no)	1·12	0·87-1·43	1·06	0·57-1·98	1·25	0·81-1·94	0·83	0·54-1·30
Marital status
Married/co-inhabitant	1·00	Reference	1·00	Reference	1·00	Reference	1·00	Reference
Single/widowed/divorced	1·04	0·91-1·18	0·90	0·63-1·26	1·29	1·06-1·57	0·92	0·75-1·13
Paternal characteristics
Age at birth (per year)	1·00	0·99-1·01	0·98	0·95-1·01	1·00	0·99-1·02	0·99	0·98-1·01
Birth characteristics
Preterm birth (yes vs. no)	0·90	0·71-1·13	1·19	0·70-2·02	0·81	0·56-1·16	0·90	0·64-1·28
Multiple birth (yes vs. no)	1·24	0·90-1·70	0·60	0·18-1·92	1·25	0·76-2·04	1·02	0·62-1·70
Cesarean delivery (yes vs. no)	0·91	0·76-1·10	1·25	0·80-1·93	1·03	0·77-1·36	0·91	0·68-1·21
Small-for-gestational age (yes vs. no)	1·09	0·83-1·43	0·54	0·20-1·50	1·09	0·72-1·65	1·15	0·77-1·73
Large-for-gestational age (yes vs. no)	1·24	0·92-1·68	0·56	0·20-1·56	1·08	0·69-1·70	1·35	0·85-2·14
Birth weight (g)
<1,500	0·74	0·30-1·85	NE	NE	NE	NE	1·27	0·38-4·21
1,500-2,499	1·00	0·78-1·29	0·88	0·42-1·85	1·10	0·77-1·59	0·96	0·64-1·44
2,500-3,499	1·00	Reference	1·00	Reference	1·00	Reference	1·00	Reference
3,500-4,499	1·08	0·98-1·19	1·51	1·17-1·95	1·14	0·99-1·32	1·19	1·02-1·37
4,500+	1·30	0·98-1·73	0·69	0·25-1·95	1·20	0·77-1·87	1·53	1·00-2·35
Birth weight (per kg)	1·11	1·02-1·21	1·38	1·10-1·75	1·20	1·05-1·37	1·17	1·03-1·34
Birth order
1	1·00	Reference	1·00	Reference	1·00	Reference	1·00	Reference
2	1·01	0·91-1·12	1·02	0·77-1·34	0·97	0·83-1·14	0·97	0·83-1·14
3	0·83	0·72-0·96	0·82	0·57-1·19	0·99	0·81-1·21	0·88	0·71-1·08
4	0·75	0·59-0·94	0·71	0·38-1·31	0·82	0·59-1·15	0·69	0·48-0·98
5+	1·02	0·77-1·34	0·53	0·21-1·32	0·98	0·66-1·47	0·75	0·48-1·18
Maternal conditions diagnosed before pregnancy
Diabetes (yes vs. no)	1·65	0·89-3·05	3·00	0·83-10·9	2·34	0·95-5·76	1·14	0·41-3·23
Hypertension (yes vs. no)	1·05	0·24-4·50	NE	NE	2·86	0·59-13·8	NE	NE
Maternal conditions diagnosed before/during pregnancy (Denmark only)
Hypothyroidism (yes vs. no)	25·1	13·5-46·5	3·33	0·35-32·1	10·0	3·97-25·2	30·1	14·2-63·8
Hyperthyroidism (yes vs. no)	11·9	6·5-21·9	17·8	3·22-98·5	11·4	4·14-31·5	5·71	2·81-11·6
Goiter (yes vs. no)	59·9	33·4-108	86·4	26·2-285	36·0	17·9-72·5	35·4	20·3-61·5
Thyroiditis (yes vs. no)	3·75	0·99-14·1	NE	NE	NE	NE	6·00	1·43-25·1
Benign neoplasms (yes vs. no)	20·0	5·00-80·0	10·0	0·63-160	NE	NE	7·50	1·68-33·5
Maternal conditions diagnosed during pregnancy
Gestational hypertension (yes vs. no)	0·69	0·45-1·06	0·91	0·32-2·55	0·86	0·46-1·59	0·59	0·29-1·21
Hyperemesis (yes vs. no)	1·02	0·60-1·74	1·68	0·58-4·90	1·27	0·63-2·55	1·48	0·76-2·89
Pregnancy anemia (yes vs. no)	0·99	0·61-1·62	1·05	0·24-4·59	0·83	0·33-2·08	1·30	0·59-2·88
Gestational diabetes (yes vs. no)	1·20	0·51-2·83	1·44	0·32-6·40	0·80	0·19-3·39	1·68	0·65-4·36
Placental abruption (yes vs. no)	0·67	0·27-1·67	1·26	0·15-10·7	0·63	0·15-2·61	0·52	0·09-3·93
Placenta previa (yes vs. no)	0·91	0·36-2·28	1·00	0·13-7·81	0·74	0·18-3·12	0·71	0·09-5·43
Preeclampsia/eclampsia (yes vs. no)	1·00	0·74-1·35	0·86	0·34-2·16	1·07	0·68-1·69	0·68	0·41-1·14
Postpartum hemorrhage (yes vs. no)	1·20	0·97-1·49	1·70	1·02-2·82	1·47	1·09-1·99	1·58	1·16-2·16
Neonatal conditions diagnosed in the first year after birth
Congenital hypothyroidism (yes vs. no)	2·22	0·48-10·3	20·0	1·81-221	13·3	2·98-59·6	2·00	0·23-17·1
Neonatal jaundice (yes vs. no)	1·33	0·85-2·07	0·37	0·05-2·79	1·21	0·57-2·58	1·64	0·88-3·05

NE= not estimable

^aFrom conditional logistic regression models, conditioned on birth year (of the case), sex, country, and county of birth