Objective: To describe a new conservative approach in the treatment of heterotopic pregnancy. Design: Case report, Setting: A university hospital and an outpatient IVF center. Intervention(s): Transvaginal ultrasonography-guided puncture of the ectopic gestational sac and instillation of hyperosmolar glucose. Result(s): The ectopic pregnancy resolved without further intervention. The intrauterine pregnancy resulted in a full-term live birth. Conclusion(s): Transvaginal injection of hyperosmolar glucose may be an effective conservative treatment for unruptured ectopic pregnancies in cases of heterotopic pregnancy. ((C) 1998 by American Society for Reproductive Medicine.).