CASE: A 32-year-old woman, Gravida 1 Para 0, was referred to our center at 7 weeks gestation in 2018 for uncontrolled diabetes mellitus diagnosed during investigation for subfertility. Her poor compliance with the treatment is consistent with an HbA1c of 8%. During the assessment, she was already complaining of lower abdominal pain. Ultrasound showed irregular IUGS with no fetal echo. She had a miscarriage soon; however, due to ultrasound evidence of thickened and irregular endometrium (17 mm) with mixed echogenicity, dilatation and curettage (D + C) were commenced. The first and second tissues were reported as the product of conception (POC) and well differentiated endometrioid adenocarcinoma, respectively. The first hysteroscopy showed foci area of polypoidal growth at the right posterior endometrium, obscuring the right ostium, with similar histology report. She was commenced on high-dose progestogen with hysteroscopy surveillance 6 months later, which showed disease regression. After two normal hysteroscopies and endometrial biopsies with continuous progestogen therapy for 12 months, cyclical progestogen for 12 months and follow-up for another 6 months, she had spontaneous conception and is currently pregnant at 16 weeks gestation.