Arrest of preterm labour and prolongation of gestation with glyceryl trinitrate, a nitric oxide donor.

13 women admitted consecutively in preterm labour were recruited to an observational study of the effect of glyceryl trinitrate (GTN) patches on uterine contractions and prolongation of pregnancy. All twenty episodes of preterm labour (at 23-33 weeks' gestation) responded. 1 patient delivered because of cervical incompetence despite cessation of uterine contractions. The mean prolongation of pregnancy was 34 days. 8 babies have been born so far, and are progressing well. GTN patches appear to be a safe, well-tolerated, and non-invasive method of suppressing uterine contractions in preterm labour.