A 33-year-old multiparous woman with a previous obstetric history of cesarean section due to breech presentation naturally conceived and was referred to our hospital at 7 weeks of gestation with suspected cesarean scar pregnancy (CSP). A transvaginal ultrasonographic examination revealed low implantation of the gestational sac (GS) with a heartbeat (Figure 1(a)). However, the anterior myometrium including the cesarean scar was intact, ruling out a diagnosis of CSP. The patient strongly desired to continue the pregnancy. She was admitted to our hospital at 13 weeks of gestation with threatened miscarriage due to genital bleeding and a shortened cervical length of 14 mm. Thereafter, a small amount of genital bleeding was occasionally observed, and the placenta was gradually inserted into the cervix with cervical shortening (Figures 1(b), 1(c), and 2). Placenta accreta was strongly suspected because an ultrasonographic examination showed the disappearance of the sonolucent zone, scattered lacunae, and abundant inflow of blood vessels in the placental space from the posterior wall to the anterior wall near the internal cervical os. Magnetic resonance imaging (MRI) at 30 weeks of gestation revealed insertion of the placenta into the effacement of the cervical canal, irregularity and thinning of the myometrium, loss of the signal at the placental muscle layer boundary, intraplacental vasodilatation, intraplacental hypointense areas, and heterogeneity within the placenta (Figure 1(d)), which strongly suggested placenta accreta. We predicted the risk of massive bleeding during delivery to be very high based on ultrasonographic images and MRI findings of placenta accreta.
After the administration of betamethasone preoperatively to promote fetal lung maturation, elective cesarean hysterectomy was performed in a hybrid operating room at 34 weeks and 1 day of gestation. Under spinal anesthesia, bilateral ureteral stents were placed by a urologist to facilitate the identification of the ureters. Resuscitative endovascular balloon occlusion of the aorta (REBOA) and a catheter for uterine artery embolization (UAE) in the right internal iliac artery were then placed by an interventional radiologist to prepare for massive bleeding during and after hysterectomy. No abnormal blood vessels or findings suggestive of CSP were detected on the anterior uterine surface around the previous cesarean scar. We performed transverse hysterotomy at the fundus of the uterus and delivered a male infant weighting 1,938 g with Apgar scores of 8/9 (1/5 minutes). We then switched to general anesthesia, followed by cesarean hysterectomy after suturing transverse hysterotomy without detaching the placenta. Regarding the incision of the previous cesarean section, the anterior wall placenta was not placenta percreta, but placenta increta; therefore, there was no bladder invasion, and the bladder was smoothly detached. The volume of bleeding was not high before the vaginal stump procedure. Since massive bleeding was expected during resection of the vaginal stump to suturing during hysterectomy, REBOA was inflated for 6 minutes from resection of the vaginal stump to suturing, and the uterus was completely removed without massive bleeding. Intraoperative blood loss was 1,770 g. Six units of red blood cells were transfused because hemoglobin decreased to 7 mg/dL with continuous bleeding during hysterectomy. The patient was transferred to the intensive care unit for close observations of the abrupt occurrence of postoperative intra-abdominal bleeding. On the next day, she was returned to the obstetrics ward and was discharged with no complications on the 8th postoperative day.
Upon gross inspection, the lower uterine segment was dilated due to the placenta, the cervix had effaced (Figure 1(e)), and the placenta was visible from the cervical os. A histopathological examination of the placenta and uterus revealed placenta previa with extensive adhesions into the anteroposterior wall, mainly into the posterior wall from the lower uterine segment to the cervix (Figures 1(f) and 1(g)). The final histopathological diagnosis was cervico-isthmic pregnancy with placenta increta at the uterine body and cervix.