Secondary postpartum bleeding is defined as abnormal uterine bleeding occurring between the 24th hour and the 12th week postpartum, affecting approximately 1–2% of postpartum women. In the c-section of a 19-year-old pregnant woman (gravida 2, para 1, c-section 1) at term with polyhydramnios, uterine atony was managed with medical treatment and hemostatic B-Lynch sutures. After being discharged on the third day with no abnormal findings, she presented with acute, abundant vaginal bleeding on postpartum day 15. The uterus was semi-contracted, with subinvolution. Ultrasound revealed a 21 mm heterogeneous area in the endometrium and adenomyosis. The bleeding was managed with uterotonics and intrauterine balloon tamponade following revision curettage, and was attributed to late atony. Due to the timing of secondary postpartum hemorrhage and its rarity, there is a high probability of misdiagnosis. To prevent serious morbidity and mortality, the etiology should be evaluated promptly, and appropriate intervention should be undertaken.
Keywords: Adenomyosis, curettage, placenta, postpartum hemorrhage, uterus.