Joint Effect of Maternal Tobacco Smoking and Pregestational Diabetes on Preterm Births and Congenital Anomalies: A Population-Based Study in Northern Italy
Table 2
Prevalence difference per 100, prevalence ratio and relative risk of preterm birth, and congenital anomalies associated with pregestational diabetes and/or tobacco smoking, Emilia-Romagna region, 2007–2010.
PGD
Smoking
Total
(%)
PD100
(95% CI)
PR
(95% CI)
RR
(95% CI)
Preterm birth
No
No
4218
317
(7.51)
Ref.
Ref.
Ref.
No
Yes
570
39
(6.84)
−0.67
(−2.89, 1.54)
0.91
(0.66, 1.25)
0.89
(0.63, 1.27)
Yes
No
888
151
(17.01)
9.48
(6.89, 12.08)
2.26
(1.89, 2.70)
2.41
(1.93, 3.02)
Yes
Yes
104
29
(27.88)
20.36
(11.67, 29.06)
3.71
(2.67, 5.15)
4.69
(2.97, 7.41)
Congenital anomalies
No
No
4218
79
(1.87)
Ref.
Ref.
Ref.
No
Yes
570
10
(1.75)
−0.12
(−1.27, 1.03)
0.93
(0.49, 1.79)
0.92
(0.47, 1.79)
Yes
No
888
24
(2.70)
0.83
(−0.31, 1.97)
1.44
(0.92, 2.26)
1.41
(0.88, 2.25)
Yes
Yes
104
5
(4.81)
2.93
(−1.22, 7.08)
2.57
(1.06, 6.23)
2.66
(1.05, 6.71)
Adjusted for maternal age at delivery, nationality, and parents’ education level. PGD = pregestational diabetes; PD = prevalence difference; PR = prevalence ratio; RR = relative risk.
