Corticotropin-releasing hormone: A biochemical predictor of preterm delivery in a pilot randomized trial of the treatment of preterm labor

Abstract

We assessed the ability of maternal plasma corticotropin-releasing hormone measurements to predict preterm delivery in the setting of a pilot study comparing transdermal glyceryl trinitrate with standard beta-mimetic therapy for preterm labor and to determine the effect of these tocolytics on maternal plasma corticotropin-releasing hormone concentrations. Twenty-six consecutive patients with preterm labor were randomized to tocolytic treatment with transdermal glyceryl trinitrate (n=13) or intravenous albuterol (n=13). Plasma corticotropin-releasing hormone immunoreactivity levels were higher in women who were delivered within 7 days (41.4+/-13.5 pmol/L) than in those continuing to term (14.2+/-2.4 pmol/L, p=0.011) and were not altered by treatment. Two women in each of the treatment groups delivered within 7 days of the initiation of treatment, two women in the glyceryl trinitrate group were changed to albuterol because of persistence of contractions. Glyceryl trinitrate treatment was associated with significantly fewer maternal side effects. Neither treatment altered umbilical artery Doppler ultrasonographic findings. Transdermal glyceryl trinitrate is better tolerated than intravenous albuterol but may be no more efficacious than albuterol for the treatment of preterm labor. Biologic markers such as plasma corticotropin-releasing hormone levels may be an important method of identifying women at high risk of preterm delivery.