The Ethics of Interstitial and Cesarean Scar Ectopic Pregnancies: Four Case Studies and a Review of the Literature

Abstract

Catholic bioethicists have extensively addressed extrauterine tubal pregnancies, which represent the great majority of ectopic pregnancies. However, additional management options have been developed for the other 7-10 percent of ectopic pregnancies. Using two cases of interstitial pregnancy and two cases of cesarean scar pregnancy (CSP) seen at a Catholic tertiary care center, this article discusses options including expectant management, systemic methotrexate, intragestational methotrexate, intragestational potassium chloride, uterine artery embolization, dilation and curettage (D&C), vasopressin use, cornuostomy, cornual wedge resection, CSP evacuation, CSP scar excision, CSP salvage, and hysterectomy. Cornual wedge resection, vasopressin use, and CSP scar excision are morally acceptable; less clearly licit are aspiration of gestational sac contents, cornuostomy, gestational excision for CSPs, and methotrexate. Certainly illicit are any techniques leading to direct abortion such as D&Cs on live embryos or fetuses, double-balloon catheter placement, and use of potassium chloride. Summary: An ectopic pregnancy is any pregnancy outside the uterus. These are dangerous because the pregnancy can burst out of its abnormal location and cause life-threatening internal bleeding. Most are in the part of the fallopian tube outside the uterus, but there are other types, including interstitial pregnancies (located in the part of the tube tunneling through the uterine wall) and cesarean scar pregnancies (buried in the uterine scar where the cut for a C-section was made). This article lists the ways that physicians prevent women from dying from interstitial and cesarean scar pregnancies and proposes which treatments are morally acceptable.

Keywords: Bioethics; Cesarean scar pregnancy; Ectopic pregnancy; Indirect abortion; Interstitial pregnancy; Methotrexate; Vasopressin.

Figure 1.

Transvaginal ultrasound of case 1 at nine weeks, midline longitudinal view, illustrating fundal gestational sac with calipers illustrating 0.26 centimeter of myometrium.

Figure 2.

Transvaginal ultrasound of case 1 at nine weeks, transverse view of the fundus, illustrating asymmetry of gestational sac.

Figure 3.

Coronal computed tomography of case 2 at seventeen weeks, showing hemoperitoneum (solid arrow) and protrusion of amniotic sac through right cornu (hollow arrow).

Figure 4.

(A) The interstitial portion of the fallopian tube and an interstitial pregnancy diagrammed with a coronal section of the uterus and proximal tubes. (B) A cesarean scar seen with a midsagittal section of the uterus. (C) Schematic of cornual wedge resection. (D) Schematic of scar excision. (E) Schematic of cornuostomy. (F) Schematic of gestational excision.

Figure 5.

Transvaginal ultrasound of case 3 at seven weeks, documenting absent fetal cardiac activity after methotrexate administration. Calipers highlight 0.61 centimeter of myometrium anterior to the gestational sac, thickened from previously distended imaging.

Figure 6.

Coronal magnetic resonance imaging of case 4, coronal view, at twenty-nine weeks. The amniotic cavity (former gestational sac) has expanded the lower uterine segment (solid arrows). Thick, unused uterine fundus can be seen at the top of the gestational sac (hollow arrow).