Comparison of gestational diabetes mellitus rates in women with increased and normal white blood cell counts in early pregnancy.

Aim: To compare the rates of gestational diabetes mellitus (GDM) among Thai or other South-East Asian women with increased and normal peripheral white blood cell (WBC) counts in early pregnancy. The risk of GDM in relation to WBC count was also determined.

Methods: We included singleton pregnant women who sought their first antenatal care in our institution between May 2010 and December 2011. Subjects were 595 gravidas with an increased WBC count while controls were 595 pregnancies with a normal WBC count. Data of pregnant women were collected. The WBC of each woman was obtained from a complete blood count performed in the first trimester. The rates of GDM between both groups were compared. The odds ratio (OR) with 95% confidence interval (CI) of GDM development in the subject group was determined by multivariate analysis.

Results: Data on 570 subjects with increased WBC and 575 controls with normal WBC were obtained. The rate of GDM was significantly higher in subjects compared to controls at 13.2% versus 5.2% (P<0.001) with a crude OR of 2.75 (95% CI, 1.77-4.28). By multivariate analysis, the subject group was found at increased risk of GDM compared to the control group, with an adjusted OR of 2.20 (95% CI, 1.39-3.47).

Conclusion: Thai or other South-East Asian women with an increased WBC count in early pregnancy had a significantly higher rate of GDM than women having a normal WBC count. Our results demonstrate that WBC count is an independent risk factor for GDM.