Table 3.

Stratified analyses of risk factors with fetal sex-divergent associations with gestational diabetes mellitus (GDM).

Risk factor	Crude RR (95% CI)	P	Adjusteda RR (95% CI)	P
Fetal sex–male (n = 1271)
GWG velocity (Z score)	1.09 (0.96–1.23)	0.201	1.09 (0.96–1.23)	0.178
Family history of diabetes	1.18 (0.78–1.78)	0.435	1.08 (0.74–1.59)	0.680
Mother age (>35, yes/no)	1.26 (0.83–1.90)	0.273	1.05 (0.71–1.56)	0.800
Alcohol drinking	1.55 (1.07–2.24)	0.020	1.51 (1.06–2.16)	0.023
Fetal sex–female (n = 1164)
GWG velocity (Z score)	1.15 (1.02–1.31)	0.024	1.17 (1.03–1.33)	0.017
Family history of diabetes	2.01 (1.45–2.79)	<0.001	1.74 (1.27–2.40)	<0.001
Mother age (>35, yes/no)	1.66 (1.09–2.53)	0.018	1.64 (1.08–2.48)	0.019
Alcohol drinking	0.94 (0.60–1.49)	0.800	0.97 (0.62–1.51)	0.878

^aThe factors in the multi-variable log-binomial models were GWG velocity Z score, pre-pregnancy BMI (category), maternal age (>35, yes/no), alcohol drinking, GDM history and family history of diabetes. Other factors were not included since they were not significant at P > 0.2 and did not affect the comparisons. P-values in tests for interaction were: 0.262 for fetal sex and GWG velocity, 0.030 for fetal sex and family history of diabetes, 0.246 for fetal sex and advanced maternal age (>35, yes/no), and 0.055 for fetal sex and alcohol drinking. The number of GDM was 190 of 1,271 women carrying a male fetus, and 190 of 1,164 women carrying a female fetus.