Introduction: An ectopic pregnancy is when a fertilized egg implants in a different location than the endometrium of the uterine cavity. Over 90% of ectopic pregnancies occur in the fallopian tube, but other locations are possible, including in the scar of a prior cesarean delivery. This weaker scar tissue can lead to uterine rupture, placenta accreta spectrum, or hemorrhage. While this is rare, at 1 in 2,000 women with prior cesarean delivery, there has been a rise in cesarean scar ectopic pregnancies as the number of cesarean deliveries has increased. On the other hand, molar pregnancies occur due to abnormal fertilization causing tumor-like growth instead of a healthy fetus or placenta. Molar pregnancies are either complete (diploid set of paternal chromosomes), or partial (triploid set from two sperm enucleating one egg or one sperm with diploid set of chromosomes). Purpose: To report an unusual presentation of a cesarean scar ectopic pregnancy. Methods: Case Report Results: We present a rare case of a previously healthy 31-year-old G7P2133 at eight weeks gestation, as dated by last menstrual period, with history of three previous cesarean sections who presented to an outside hospital with a two-week history of brown vaginal spotting. In addition, she experienced lower abdominal cramping and nausea without associated vomiting. She was found to have an elevated beta-hCG level of 198,086 mlU/ml and was transferred to our hospital due to concern for molar pregnancy. Upon ultrasound, findings were concerning for a potential partial molar pregnancy as well as cesarean section scar ectopic pregnancy. The findings were confirmed with Magnetic Resonance Imaging (MRI), which showed the gestational sac involving the cesarean scar and the additional complication of potential extrauterine invasion of the possible molar pregnancy through the anterior mid-body uterine serosa into the anterior abdominal wall and along the uterine cesarean scar in the lower uterine segment. As the patient stated she had completed childbearing, she consented to a robotic assisted total laparoscopic hysterectomy with bilateral salpingo-oophorectomy performed by Gynecologic Oncology. The Beta-hCG was 149,376 mlU/ml on the day of surgery. During the surgery, significant infiltration of the placental tissue was noted, creating adhesions between the uterus, the anterior abdominal wall, and the bladder. After the specimen was removed, it was bivalved and cystic trophoblastic tissue was noted in the fundus with almost complete myometrial invasion. Her postoperative recovery was unremarkable. She met all postoperative milestones and was discharged on postoperative day one. She continued to follow with Gynecology Oncology, where cytogenetics showed no chromosomal abnormalities. While this was not a true molar pregnancy, the cesarean scar ectopic and the placenta percreta still made this a life-threatening pregnancy. Conclusions: While our patient had a classic presentation for a molar pregnancy including vaginal spotting, an elevated beta hCG, and concerning imaging findings, her cytogenetics were negative for any chromosomal abnormalities. Regardless, the cesarean scar ectopic pregnancy compounded by placenta accreta spectrum with placenta percreta imposed significant risk for the mother and was successfully navigated with early surgical intervention.
Brookins et al. (Sat,) studied this question.