When a solution of hypertonic saline is instilled into the amniotic sac, approximately 15% of the women will not have aborted within 72 hours. The purpose of this study was to determine whether the concentration of sodium in amniotic fluid at the end of the procedure was the critical factor affecting the latent period between instillation and delivery. It was learned that if the concentration of sodium was more than 2000 mEq/liter, it was not the critical factor affecting onset of labor. Management of the woman with delayed onset of labor after hypertonic saline was instilled is discussed.