Association of leukocyte counts in the first trimester with glucose intolerance during pregnancy

We investigated the association between leukocyte counts and glucose challenge test (GCT) level during pregnancy.

We collected prenatal information of women who had their first clinic visit in early pregnancy. Women underwent GCT at 24-28 gestational weeks, and a result of ≥7.8 mmol/L was considered positive. Participants were divided into quartiles of leukocyte counts, and association with GCT results and positive rate were analyzed by logistic regression.

Among 20,707 pregnant women, the median of leukocyte counts was higher in the positive group than the normal group (8.5 × 10⁹ /L vs 8.2 × 10⁹ /L, P < 0.01). There was a linear trend in GCT results and positive rate with increasing leukocyte quartiles. Compared with the lowest quartile, the highest leukocyte quartile (>9.70 × 10⁹ /L) was significantly associated with positive GCT results (adjusted odds ratio 1.378, 95% confidence interval 1.246-1.524), and the linear relationship between increased risk of positive result and increasing leukocyte quartiles persisted (P for linear trend <0.01). In multivariable analysis, the risk of a positive result increased by 2.2% with each 1-unit increase in leukocyte counts (adjusted odds ratio 1.022, 95% confidence interval 1.011-1.033).

Elevated leukocyte counts in early pregnancy were independently and linearly associated with the risk of positive GCT levels, indicating that inflammation might play an important role in the development of gestational diabetes mellitus.