Rare case of cesarean scar pregnancy diagnosed late: a report

The patient reported that her last menstrual period was just 5 to 6 weeks prior. However, USG revealed a gestational sac in the anterior lower uterine segment with a fetus measuring 4.83 cm crown-rump length (CRL) with positive cardiac activity, corresponding to 11 weeks and 6 days of gestation. Colour/power Doppler images depicted a hyperechoic rim of a choriodecidual reaction with excessive vascularity (Fig. 1). Although we could observe a definitive abnormally located gestational sac, our patient did not have any pain during the physical examination. She admitted that her last menstrual period was different from her usual menstrual periods. Because CSP or cervical pregnancy was suspected, we performed computed tomography (CT) for a definitive diagnosis. The CT scan showed an intrauterine gestational sac in the lower uterine segment bulging through the anterior uterine wall at the site of the cesarean scar. No invasion of the urinary bladder was observed (Fig. 1). On presentation, her β-human chorionic gonadotropin (β-hCG) level was 66,536.8 IU/L (Day 1). Initially, we injected 50 mg of methotrexate (MTX) mixed with 9 mL of normal saline in the amniotic sac through a 22-G needle transabdominally under USG guidance. Simultaneously, 2 ml of amniotic fluid was aspirated for termination of the pregnancy. However, fetal cardiac activity was still observed 2 days later (Day 3), without significant changes in the serum β-hCG levels (65,342.5 IU/L). We decided on laparotomy instead of laparoscopy because of the large CRL (Day 4). The intraoperative finding showed bloody amniotic fluid, blood clot, placenta, and a fetus at the lower segment of the uterus. A transverse uterine incision was made at the lower segment of the uterus (Fig. 2). The gestational sac was removed, as well as most of the trophoblastic tissues that were adherent and invading the wall of the lower uterine segment. The fetus and placenta showed no definitive abnormalities (Fig. 2). The estimated blood loss was 1.2 L at intra-operation, without immediate complication. The uterine defect was repaired into two layers by using 2–0 Vicryl sutures. Our patient received 3 units of packed red blood cells (PRBC) at the ward postoperatively. The serial β-hCG level was 1958 IU/L at 4 days after the surgery (Day 8). She was discharged in good condition 5 days after the operation (Day 9). After 1 month (Day 39), her β-hCG levels returned to normal (2.8 IU/L). She was very satisfied with the fact that she had recovered well without the need for intensive care or further treatment without the need for hysterectomy.