17-alpha hydroxyprogesterone (17P) may reduce preterm deliveries, but it doesn't seem to reduce perinatal deaths. At least that's the conclusion of a large study reported at this year's Annual Clinical Meeting. To reach that conclusion, University of Miami investigators examined a database of high-risk patients with prior preterm deliveries (PTD) (n=699) and current singleton gestations who had been receiving weekly 250 mg IM injections of 17P, or observation (n=880). While those on progesterone delivered at 36.2 weeks (+/- 4.2), compared to 35.5 weeks ( +/- 4.2) (P<0.001), there were no significant differences between the groups when researchers looked at the incidence of stillbirths, neonatal deaths, miscarriages at less than 24 weeks, or total perinatal deaths.
Gonzalez-Quentero VH, Smarkusky L, Carter J, et al. 17-alpha-hydroxyprogesterone caproate: perinatal mortality and pregnancy outcomes. Obstet Gynecol. 2007;109(suppl):7S.