Joint Effect of Maternal Tobacco Smoking and Pregestational Diabetes on Preterm Births and Congenital Anomalies: A Population-Based Study in Northern Italy
Table 3
Prevalence difference per 100, prevalence ratio and relative risk of preterm birth, and congenital anomalies associated with pregestational diabetes and/or tobacco smoking, Provinces of Modena and Reggio Emilia, 2007–2010.
PGD
Smoking
Total
(%)
PD∗100
(95% CI)
PR
(95% CI)
RR
(95% CI)
Preterm birth
No
No
449
40
(8.91)
Ref.
Ref.
Ref.
No
Yes
64
7
(10.94)
2.02
(−6.12, 10.17)
1.23
(0.57, 2.64)
1.30
(0.55, 3.08)
Yes
No
100
30
(30.01)
21.09
(11.68, 30.49)
3.37
(2.21, 5.14)
3.94
(2.25, 6.92)
Yes
Yes
8
3
(37.50)
28.6
(−7.37, 64.55)
4.21
(1.55, 11.51)
5.99
(1.37, 26.29)
Congenital anomalies
No
No
449
6
(1.34)
Ref.
Ref.
Ref.
No
Yes
64
3
(4.69)
3.35
(−1.97, 8.67)
3.51
(0.89, 13.81)
4.46
(1.04, 19.09)
Yes
No
100
6
(6.01)
4.66
(−0.13, 9.46)
4.49
(1.47, 13.71)
4.01
(1.22, 13.18)
Yes
Yes
8
1
(12.50)
11.16
(−13.36, 35.68)
9.35
(1.13, 77.62)
12.91
(1.30, 127.75)
Adjusted for maternal age at delivery, nationality, and parents’ education level. PGD = pregestational diabetes; PD = prevalence difference; PR = prevalence ratio; RR = relative risk.
