Sleep disturbances increase interleukin-6 production during pregnancy: implications for pregnancy complications.

Pregnant women experience disturbed sleep that varies throughout the gestational period. In clinical studies of nonpregnant cohorts, data link disturbed sleep with increases in inflammatory markers. Emerging evidence has also found associations between increased inflammation and medical morbidity, including various pregnancy complications. The authors have previously shown a correlation between sleep disturbances and serum cytokine levels. They extend this initial observation by evaluating the relationship between sleep during mid and late pregnancy and inflammatory cytokines in both serum and stimulated peripheral blood mononuclear cells. Subjective sleep during pregnancy, described by the Pittsburgh Sleep Quality Index and sleep diaries, and circulating and stimulated measures of interleukin (IL)-6 and tumor necrosis factor (TNF)-alpha were evaluated in 19 pregnant women. The authors found that greater sleep complaints in late pregnancy were associated with both increased circulating and stimulated IL-6 levels. Short sleep duration and poor sleep efficiency in both mid and late pregnancy were associated with higher stimulated levels of IL-6. No relationships were observed for TNF-alpha. These preliminary findings indicate that women who experience sleep disturbances as early as mid gestation are likely to have an increase in inflammation.