OBJECTIVE: To report a case of a triplet heterotopic caesarean scar pregnancy (CSP) with two gestational sacs implanted in the caesarean scar after in vitro fertilization-embryo transfer. DESIGN: Case report. SETTINGS: Private reproductive medicine center and obstetric department of a university hospital. PATIENT(S): A 31-year-old woman with previous caesarean section affected by secondary infertility related to male azoospermia. INTERVENTION(S): In vitro fertilization-embryo transfer followed by early ultrasound diagnosis of heterotopic CSP and selective embryo reduction performed by transvaginal ultrasound-guided potassium chloride and methotrexate injection in the ectopic gestational sacs. MAIN OUTCOME MEASURE(S): Successful pregnancy outcome. RESULT(S): An ongoing intrauterine pregnancy with a live birth after successful management of ectopic gestational sacs. CONCLUSION(S): Triplet heterotopic CSP with two ectopic gestational sacs may occur after IVF-ET and, to our knowledge, this is the first time such a complication has been reported. Ultrasound is the main tool allowing early diagnosis of this condition, and the injection of potassium chloride and methotrexate is a safe and efficacious treatment method. The gynecologist managing early pregnancy should be aware of the possibility of CSP, and patients must be appropriately counseled about the different treatment options.