Table 2.

Characteristics of women and their offspring, according to whether the woman was exposed to extra vitamin D from food fortification in fetal life or not; women born between June 1983 and August 1988, who gave birth to their first child at age 14·5 to 27·5 years

	Exposed			Unexposed
Characteristic	N	Median	5th–95th percentile	N	Median	5th–95th percentile	P value
Age at delivery* (years)	15 733	24·9	19·5–27·3	16 888	24·7	19·4–27·3	<0·0001
		n	%		n	%
Outcome†	15 733			16 888
Gestational hypertension‡		235	1·5		260	1·5	0·7
Mild to moderate and unspecified pre-eclampsia§		475	3·0		595	3·5	0·01
Severe pre-eclampsia, HELLP syndrome and eclampsia¶		185	1·2		212	1·3	0·5
All above		895	5·7		1067	6·3	0·02
Pre-pregnancy BMI†,║	13 640			14 781			0·02
<18·5 kg/m2		609	4·4		772	5·2
18·5–24·9 kg/m2		8251	60·5		8821	59·7
25·5–29·9 kg/m2		2930	21·5		3127	21·2
≥30·0 kg/m2		1850	13·6		2031	13·9
Smoking status during pregnancy†	15 733			16 888			<0·0001
Current smoker		2968	18·9		2670	15·8
Former smoker		799	5·1		969	5·7
Non-smoker		11 966	76·0		13 249	78·5
Singleton or multiple pregnancy†	15 733			16 888			0·38
Singleton		15 547	98·8		16 670	98·7
Multiple		186	1·2		218	1·3
Gestational age at delivery (weeks)†	15 733			16 888			<0·0001
<37		1120	7·1		1185	7·0
37+0 to 37+6		822	5·2		866	5·1
38+0 to 38+6		1950	12·4		2026	12·0
39+0 to 39+6		3362	21·4		3538	21·0
40+0 to 40+6		4419	28·1		4946	29·3
41+0 to 41+6		3092	19·7		3712	22·0
≥42		968	6·1		615	3·6
Offspring’s gender†	15 733			16 888			0·05
Female		7742	49·2		8151	48·3
Male		7991	50·8		8737	51·7

HELLP, haemolysis, elevated liver enzymes, low platelets; ICD-10, International Statistical Classification of Diseases and Related Health Problems 10th Revision.

^*Tested by the Mann–Whitney rank-sum test.

^†Tested by the χ ² test.

^‡ICD-10 code: O13.9.

^§ICD-10 codes: O14.0 and O14.9.

^¶ICD-10 codes: O14.1, O14.2 and O15.0.

^║Information available only from 2004 and forwards.