Table 2

Demographic factors at time of second pregnancy in relation to interpregnancy interval in women with previous term live birth (n=69 055). Values are numbers (percentages)

Interpregnancy interval (months)
1-5 (n=3282)6-11 (n=8999)12-17 (n=12 220)18-23 (n=11 793)24-59 (n=32 761)Total (n=69 055)P value
Height (cm):
<155349 (10.6)843 (9.3)1 068 (8.7)1 125 (9.5)3 614 (11.0)6 990 (10.1)
155-1702654 (80.9)7160 (79.6)9 868 (80.8)9 398 (79.7)26 299 (80.3)55 379 (80.2)<0.001
>170279 (8.5)1005 (11.2)1 284 (10.5)1 270 (10.8)2 848 (8.7)6 686 (9.7)
Age (years):
<20547 (16.7)669 (7.4)501 (4.1)278 (2.4)234 (0.7)2 229 (3.2)
20-352624 (80.0)7899 (87.8)11 120 (91.0)10 961 (92.9)30 655 (93.6)63 259 (91.6)<0.001
>35111 (3.4)431 (4.8)599 (4.9)554 (4.7)1 872 (5.7)3 567 (5.2)
Marital status:
Married1949 (59.4)6714 (74.6)9 681 (79.2)9 615 (81.5)25 315 (77.3)53 274 (77.2)
other1333 (40.6)2285 (25.4)2 539 (20.8)2 178 (18.5)7 446 (22.7)15 781 (22.8)<0.001
Deprivation category:
1 (least deprived)484 (14.8)1919 (21.3)2 933 (24.0)2 720 (23.1)6 045 (18.4)14 101 (20.4)
2-41915 (58.4)5397 (60.0)7 242 (59.3)7 104 (60.2)19 809 (60.5)41 467 (60.0)<0.001
5 (most deprived)883 (26.9)1683 (18.7)2 045 (16.7)1 969 (16.7)6 907 (21.1)13 487 (19.5)
Smoking status:
Non-smoker1839 (56.0)6078 (67.5)8 560 (70.0)8 309 (70.5)21 279 (65.0)46 065 (66.7)
Ex-smoker193 (5.9)536 (6.0)797 (6.5)759 (6.4)2 533 (7.7)4 818 (7.0)<0.001
Smoker1250 (38.1)2385 (26.5)2 863 (23.4)2 725 (23.1)8 949 (27.3)18 172 (26.3)