Table 1.

Selected Baseline, Pregnancy, and Reproductive Characteristics of Northern Sweden Maternity Cohort Participants Included in the Current Study, 1975–2001

Characteristic	Cases (n = 210)			Controls (n = 357)
	Mean (SD)	No.	%	Mean (SD)	No.	%
Age at blood donation, years	30.9 (4.8)			31.0 (4.8)
Age at diagnosis, years	43.3 (6.8)
Lag time to diagnosis, years	12.3 (5.5)
Primiparous at blood donation		102	49		176	49
Age at first birth (all women), years	26.7 (4.8)			26.4 (4.8)
Parity by diagnosis (index) date
1		27	13		49	14
2		102	49		148	42
3		61	29		111	31
>3		20	10		49	14
Gestational day at blood donation	76.1 (21.5)			77.8 (19.8)
Gestational week at blood donation
<8		30	14		43	12
8–14		149	71		259	73
>14		31	15		55	15
Child's birth weight, g	3,432 (512)			3,461 (564)
Child's birth length, cm	50 (2.3)			50 (2.5)
Placental weight, ga	575 (117)			595 (137)
Male gender		100	48		164	46
Maternal weight at enrollment, kg	61.8 (8.6)			62.5 (8.7)
Maternal height, cm	165 (5.7)			165 (5.9)
Smoking at blood donation
Yes		68	32		90	25
No		136	65		262	73
Missing data		6	3		5	1
Human chorionic gonadotropin residualsb	−0.07 (0.55)			0.05 (0.49)c
α-fetoprotein residualsd	0.04 (0.80)			0.01 (0.85)c

Abbreviation: SD, standard deviation.

^aData were available for 173 cases and 290 controls.

^bData were available for 173 cases and 294 controls.

^cPaired t test for difference between cases and controls: P = 0.04 for human chorionic gonadotropin and P = 0.83 for α-fetoprotein.

^dData were available for 204 cases and 349 controls.