Inefficacy of 17 alpha-hydroxyprogesterone caproate in the prevention of prematurity in twin pregnancy.

There are indications that prophylactic administration of 17 alpha-hydroxyprogesterone caproate (17 alpha-OHP-C) could be beneficial in the treatment of women at risk for preterm delivery. Since twin pregnancy is commonly associated with prematurity, 77 women with twin pregnancy were treated during the last trimester until the 37th gestational week with weekly injections of either 17 alpha-OHP-C or a placebo, following double-blind principles. The gestational length and birth weight and the outcome of the neonates were similar in both groups. The administration of 17 alpha-OHP-C thus seems ineffective in the prevention of prematurity risks associated with twin pregnancy.