Hysteroscopic resection effective for treating cesarean scar ectopic pregnancy

Hysteroscopic resection effective for treating cesarean scar ectopic pregnancy | Image Credit: © Svitlana - © Svitlana - stock.adobe.com.

Hysteroscopic resection increases the success rate when treating cesarean scar ectopic pregnancy (CSP) compared to ultrasound-guided dilation and evacuation (D&E), according to a recent study published in the American Journal of Obstetrics & Gynecology.

CSP is an ectopic pregnancy where the fertilized egg is implanted in fibrous tissue or muscle of a previous cesarean delivery scar. Cases with positive embryonic or fetal heart activity have increased rates of maternal morbidity such as early uterine rapture, severe hemorrhage, severe placenta accrete, and hysterectomy.

Operative hysterectomy has recently been considered for treating CSP, with potential safety and efficacy benefits over standard methods such as ultrasound-guided D&E. To compare the success rate of hysteroscopic resection vs ultrasound-guided D&E when treating CSP, investigators conducted a single-center, parallel group randomized clinical trial.

The trial occurred at the University of Naples Federico II in Naples, Italy, between February 2020 and August 2022. Participants were women with singleton pregnancies at under 8 weeks and 6 days of gestation and a myometrial layer thickness of 1 mm or more. These women were randomized to receive either hysteroscopic resection or ultrasound-guided D&E.

Exclusion criteria included aborting intrauterine pregnancy, diagnosis of cervical pregnancy, other anomalous implantation site, and negative fetal heart activity. Women were included if they had CSP with positive embryonic heart activity and decided to pursue termination of pregnancy.

CSP was diagnosed using criteria described by Timor-Tritsch et al. This includes visualization of an empty uterine cavity and endocervical canal, placenta or gestational sac in the hysterotomy scar, triangular gestational sac in the niche of a scar, a thin myometrial layer between the gestational sac and bladder, a closed and empty cervical canal, an embryonic or fetal pole, and a rich vascular pattern at or in the cesarean scar.

Women randomized to receive hysteroscopic resection were in the intervention group, while those randomized to receive ultrasound-guided D&E were in the control group. Both groups received a 50 mg/m2 injection of methotrexate (MTX) before either hysteroscopic resection or ultrasound-guided D&E.

The success rate was the primary outcome of the analysis, defined by study authors as, “no further treatment required until complete resolution of the CSP.” Secondary outcomes included intraoperative and postoperative complications, use of additional procedures, length of stay (LOS) in the hospital, maternal intensive care unit (ICU) admission, and maternal death.

There were 54 women included in the final analysis, with 27 randomized to each group. Women were aged a mean 34 years and had 1 to 3 prior cesarean deliveries. A third dose of MTX was administered because of persistent fetal heart activity to 25.9% of the intervention group and 11.1% of the D&E group.

The success rate was greater in the intervention group than the control group, at 100% and 81.5% respectively. Additional procedures were required in 5 individuals in the control group, open hysterectomy in 3, and laparotomic uterine segmental resection in 1.

Hemorrhage rates were 3.7% in the intervention group and 14.8% in the control group. The intervention group had a hospital LOS of 9.0±2.9 days vs 10.0±3.5 days in the control group. Neither group reported cases of ICU admission or maternal death.

These results indicated increased success from hysteroscopic resection compared to ultrasound-guided D&E for treating CSP. Investigators concluded hysteroscopy has a significant advantage over ultrasound-guided procedures.

Reference

Di Spiezio Sardo A, Zizolfi B, Saccone G, et al. Hysteroscopic resection vs ultrasound-guided dilation and evacuation for treatment of cesarean scar ectopic pregnancy: a randomized clinical trial. American Journal of Obstetrics & Gynecology. 2023;229(4). doi:10.1016/j.ajog.2023.04.038