Effect of human immunodeficiency virus infection on serum beta(2)-microglobulin levels in pregnant women

Objective: To assess serum beta(2)-microglobulin levels in human immunodefi ciency virus (HIV)-infected and uninfected pregnant women, variations of se rum beta(2)-microglobulin levels during pregnancy and postpartum, factors t hat might influence beta(2)-microglobulin levels in pregnant women, and the association between beta(2)-microglobulin and perinatal HIV-1 transmission . Methods: We assayed 374 stored (-70C) serum samples from pregnant women enr olled in the Newark perinatal HIV-1-transmission study and 18 nonpregnant w omen for beta(2)-microglobulin using a microparticulate enzyme immunoassay. The Student t test, Wilcoxon rank test, binomial test, and Spearman correl ation coefficient were used for statistical analysis, with P <.05 considere d statistically significant. A linear regression model was used to assess t he effect of independent variables on serum beta(2)-microglobulin levels. Results: There were no significant differences (P =.16) in serum beta(2)-mi croglobulin levels between pregnant and nonpregnant HIV-negative women (1.0 7 +/- 0.35 versus 0.99 +/- 0.18 mg/L). beta(2)-Microglobulin levels did not vary throughout pregnancy and postpartum, irrespective of HIV serostatus. Substance abuse did not alter beta(2)-microglobulin levels. Human immunodef iciency virus infection caused significant increases of this surrogate mark er, but it could not discriminate among disease stages. beta(2)-Microglobul in levels at delivery were lower among women who delivered HIV-infected inf ants. Conclusion: Human immunodeficiency virus infection was associated with incr eased serum beta(2)-microglobulin levels in pregnant women and was the most significant correlate of increases of that marker. Pregnancy and substance use during pregnancy did not influence levels of serum beta(2)-microglobul in significantly. (Obstet Gynecol 1999;94:537-42. (C) 1999 by The American College of Obstetricians and Gynecologists.).