There is limited information about uterine hyperstimulation after low-dose prostaglandin E2 therapy. The purpose of this retrospective study was to describe our combined experience with this undesired effect by use of three techniques for prostaglandin E2 administration. Uterine hyperstimulation was present if the contraction frequency was more than five in 10 minutes or if contractions exceeded 2 minutes in duration. A total of 181 cases were evaluated during a 51-month period. The rates of hyperstimulation were 7.3% (167/2297) in the group that received intravaginal tablets (3.0 mg), 2.9% (12/408) with intravaginal gel (2.5 mg), and 0.5% (2/394) with intracervical gel (0.5 mg). Hyperstimulation usually began within the first hour for the group that used gel and within the first 4 hours for the tablet group. A beta 2-adrenergic drug (hexoprenaline or terbutaline) was infused routinely without adverse effects and with rapid resolution of the worrisome findings in 178 (98.3%) cases. The remaining three cases required cesarean delivery and had no evidence of neonatal compromise. We conclude from this large, combined series that uterine hyperstimulation after low-dose prostaglandin E2 therapy is uncommon and usually rapidly reversible with beta 2-adrenergic therapy without apparent untoward effects.