Table 1

Sociodemographic, lifestyle and obstetrics characteristics among pregnant women, from the INMA Project, Spain (2003–2008)

All cohorts (n=2332)Asturias (n=434)Guipuzcoa (n=521)Sabadell (n=597)Valencia (n=780)p Value*
Maternal age (>30 years), % (n)50.1 (1168)59.7 (259)55.1 (287)47.1 (281)43.2 (341)<0.001
Maternal education, % (n)
 Primary school or less24.0 (560)16.8 (73)11.3 (59)28.0 (167)33.5 (261)<0.001
 Secondary school41.6 (970)45.2 (196)35.3 (184)42.9 (256)42.8 (334)
 University studies34.4 (802)38.0 (165)53.4 (278)29.1 (174)23.7 (185)
Paternal education, % (n)
 Primary school or less35.5 (829)28.8 (125)24.4 (127)36.0 (215)46.4 (362)<0.001
 Secondary school44.5 (1037)49.1 (213)50.5 (263)43.2 (258)38.8 (303)
 University studies20.0 (466)22.1 (96)25.1 (131)20.8 (124)14.7 (115)
 Tobacco smoking (during first trimester), % (n)18.1 (423)17.7 (77)11.9 (62)15.2 (91)24.7 (193)<0.001
 Alcohol intake (during first trimester), % (n)29.9 (698)21.9 (95)36.1 (188)30.0 (179)30.3 (236)<0.001
Pre-pregnancy BMI in kg/m2, % (n)
 <2573.3 (1710)69.1 (300)80.4 (419)72.2 (431)71.8 (560)0.001
 25.0–29.918.7 (436)22.6 (98)14.6 (76)19.6 (117)18.6 (145)
 ≥308.0 (186)8.3 (36)5.0 (26)8.2 (49)9.6 (75)
 Unplanned pregnancy, n (%)16.7 (389)12.4 (54)9.6 (50)15.6 (93)24.6 (192)<0.001
 Parity (≥1), n (%)43.3 (1009)38.2 (166)44.9 (234)43.2 (258)45.0 (351)0.112
 Previous abortions (yes), n (%)23.5 (549)23.7 (103)20.5 (107)25.5 (152)24.0 (187)0.270
 Private gynaecology (visit during first trimester), n (%)34.2 (797)50.2 (218)26.1 (136)29.5 (176)34.2 (267)<0.001
 Dietary folate intake in µg/day 1st period1, GM (mean, SD)293.5 (307.8, 96.3)305.0 (320.6, 103.5)302.5 (314.6, 90.3)285.3 (298.2, 90.8)287.6 (303.3, 99.3)<0.001
 Folic acid supplements intake in µg/day 1st period1, GM (mean, SD)450.9 (1029.4, 1626.6)610.0 (1180.8, 1613.0)585.5 (1331.9, 1788.1)353.4 (770.6, 1401.3)390.8 (941.0, 1643.7)<0.001
 Dietary folate intake in µg/day 2nd period2, GM (mean, SD)290.4 (304.7, 96.1)296.2 (312.1, 100.9)303.6 (313.0, 80.2)289.8 (302.4, 90.2)279.2 (296.8, 106.4)0.007
 Folic acid supplements intake in µg/day 2nd period2, GM (mean, SD)631.1 (870.6, 1683.8)1014.7 (1975.2, 2267.5)666.4 (541.5, 1523.2)409.3 (216.1, 843.1)524.7 (977.6, 1561.5)<0.001
  • 1: First period covers the months from preconception to the first trimester of pregnancy; 2: second period covers the months from the first to the third trimester.

  • *p Value from χ2 test (categorical variables) and analysis of variance (continuous variables).

  • GM, Geometric mean.