Table 1.

Infant and maternal characteristics of children in the 3-state analyses (1970–2014)

	Controls				Cases
	Males N  = 33,295	Females N  = 31,144	Total N  = 64,439		Males N  = 6,924	Females N  = 5,708	Total N  = 12,632
Birthweight (grams)
mean (standard deviation)	3,477	3,350	3,416		3,504	3,386	3,450
>350 – <2,500	1,663	1,877	3,540		352	341 (6.0)	693
2,500 – <3,000	3,850	4,881	8,731		770	820	1,590
3,000 – <3,500	10,886	12,124	23,010		2,096	2,067	4,163
3,500 – <4,000	11,439	9,090	20,529		2,484	1,822	4,306
≥4000	5,350	3,068	8,418		1,203	640	1,843
Missing	107	104	211		19	18	37
Gestational age (weeks)
mean (standard deviation)	39.3	39.4	39.4		39.2	39.3	39.2
<37	2,651	2,182	4,833		574	448 (8.3)	1,022
37–38	5,816	5,078	10,894		1,265	999	2,264
39–40	14,416	13,975	28,391		3,141	2,592	5,733
41	5,061	4,747	9,808		946	808	1,754
≥42	3,636	3,612	7,248		651	579	1,230
Missing	1,715	1,550	3,265		347	282	629
Maternal Race
Non-Hispanic, white	27,817	26,024	53,841		6,002	4,988	10,990
Hispanic	1,488	1,358	2,846		283	204 (3.6)	487
Other	3,618	3,395	7,013		597	461 (8.2)	1,058
Missing	372	367	739		42	55	97
Maternal Education
≤High school	12,097	11,175	23,272		2,614	2,222	4,836
Some college	6,051	5,812	11,863		1,491	1,136	2,627
College graduate	6,181	5,800	11,981		1,506	1,223	2,729
Missing	8,966	8,357	17,323		1,313	1,127	2,440
Birth year
1970–1984	7,796	7,172	14,968		1,624	1,347	2,971
1985–1990	8,719	8,174	16,893		1,997	1,640	3,637
1991–1996	8,806	8,235	17,041		1,659	1,428	3,087
1997–2010	7,974	7,563	15,537		1,644	1,293	2,937
State
Minnesota	14,674	13,999	28,673		3,316	2,638	5,954
New York	6,280	5,759	12,039		2,393	1,964	4,357
Washington	12,341	11,386	23,727		1,215	1,106	2,321