Tuboovarian abscess is a rare complication of IVF treatment, which can be lethal on rupture. Hereby, we present a case of a ruptured tubo-ovarian abscess, following transvaginal ultrasound-guided oocyte retrieval for IVF and transcervical embryo trasfer in a 38-year-old white female patient with five years of primary infertility who underwent aspiration of bilateral hydrosalpinges at the time of oocyte retrieval. This case suggests that the reactivation of latent pelvic infection due to a previous pelvic inflammatory disease (PID) was the possible route of infection after transvaginal ultrasound-directed follicle aspiration--transcervical embryo transfer. We conclude that physicians should consider the diagnosis of tubo-ovarian abscess in the differential diagnosis of abdominal pain, fever and leukocytosis after ovum retrieval and transcervical embryo transfer for IVF treatment. Preservation of the uterus and unaffected uterine adnexa should be attempted in such cases if future pregnancy is desired.