Studies of the mode of action of intra-amniotic injection of hypertonic solutions in the induction of labor

1.1. The literature describing the applications of amniocentesis to the induction of labor has been reviewed.2.2. The induction of labor has been attempted in 25 patients with dead or nonviable fetuses by the intra-amniotic injection of 50 per cent glucose solutions. Seventeen patients went into labor following a single injection. In 4 of the remainder, a second injection was made, and 3 of these were successfully induced.3.3. Serial studies of urinary pregnanediol, estrone, estradiol, and estriol excretion and blood levels of progesterone, estrone, estradiol, and estriol were made before and after the induction of labor by the intra-amniotic injection of 50 per cent dextrose.4.4. The success or failure of this method of induction is not dependent on the level of urinary estriol or pregnanediol.5.5. Successful induction is not associated with a maintained reduction in urinary pregnanediol excretion or blood progesterone levels.6.6. Urinary excretion and blood levels of estrogens follow a complicated pattern following induction.7.7. The significance of these results is discussed in relation to the mode of action of the intra-amniotic injection of hypertonic solutions in inducing labor.