Live Unilateral Ectopic Twin Pregnancy in a 29-Year-Old Primigravid Woman: A Case Report and Literature Review

Introduction

Ectopic pregnancy is defined as implantation of a fertilized ovum outside the endometrial cavity of the uterus, and the fallopian tubes represent the most common site of implantation [1]. This implantation remains a key cause of maternal mortality during the first trimester, primarily due to the risk of tubal rupture, which can result in hemoperitoneum, hemorrhagic shock, and death [2]. In the United States, ectopic pregnancy is associated with approximately 31.9 pregnancy-related deaths per 100 000 pregnancies [3]. The estimated incidence in the general population is approximately 1 in 100 pregnancies [4]. In contrast to singleton ectopic pregnancies, twin ectopic pregnancies occur in approximately 1 in 20 000 to 1 in 125 000 pregnancies [4–6]. During the century after the first case of unilateral tubal twin pregnancy was reported by De Ott in 1891 [7], an average of 1 case per year was described in the literature [8].

According to the European Society of Human Reproduction and Embryology (ESHRE) Working Group on Ectopic Pregnancy, ectopic pregnancies are classified as intrauterine or extrauterine. Intrauterine ectopic pregnancies are defined by evidence of trophoblastic invasion beyond the endometrial-myometrial junction while remaining confined within the uterine visceral or broad ligament peritoneum [1]; these include cesarean scar, cervical, and intramural pregnancies [9]. Extrauterine ectopic pregnancies include tubal, ovarian, and abdominal pregnancies, as well as rare implantation sites (eg, pelvic wall, liver, retroperitoneum, and rectum) [1,10–12].

This case is presented because of its rarity and clinical significance, and to emphasize the diagnostic and management challenges it poses. Early and accurate diagnosis with transvaginal ultrasound is essential to guide appropriate treatment and prevent complications. Given the absence of specific management guidelines for twin ectopic pregnancies, this report contributes to the existing literature by highlighting laparoscopic salpingectomy as a safe and effective management option in such cases.

This case report was prepared in accordance with the CARE Guidelines to ensure transparency and completeness of reporting. The patient provided written informed consent for publication of this report and the accompanying clinical details. Follow-up care was conducted in accordance with standard postoperative protocols.

Case Report

A 29-year-old Eastern European primigravid woman at 5 weeks and 6 days (by last menstrual period) was referred to our hospital with a suspected pregnancy of unknown location. On the day of presentation, she was asymptomatic, and her vital signs were within normal limits. She denied in vitro fertilization and had no history of prior tubal surgery, pelvic inflammatory disease, chlamydia infection, or intrauterine device use. However, she reported ovulation induction with letrozole (an aromatase inhibitor) and clomiphene (a selective estrogen receptor modulator). Her beta-human chorionic gonadotropin (β-hCG) level was 7385 mIU/mL. She had no history of chronic medical conditions or prior surgical procedures. Gynecologic examination revealed a slightly enlarged uterus without palpable adnexal or abdominal masses. On transvaginal ultrasound, the endometrium appeared inhomogeneous and displayed thickness of 16.3 mm; a pseudogestational sac measuring 2.9 mm was located above the internal os. In the right adnexal region, 2 live ectopic pregnancies were identified (Figure 1). The first demonstrated a gestational sac measuring 11.8 mm, yolk sac measuring 3.7 mm, and crown-rump length of 4.4 mm, corresponding to 6 weeks and 1 day (±4 days) of gestation (Figure 2). The second demonstrated a gestational sac measuring 8.1 mm, corresponding to approximately 5 weeks and 2 days of gestation, with a yolk sac measuring 4.4 mm and crown-rump length of 3.5 mm, corresponding to 6 weeks and 0 days (±4 days) of gestation (Figure 3). Each embryo exhibited fetal cardiac activity with a heart rate of approximately 114 beats per minute. A small amount of inhomogeneous fluid was noted in the pouch of Douglas.

Based on clinical and ultrasonographic assessment, the patient was scheduled for laparoscopy. Intraoperatively, a small amount of fresh blood was observed in the pouch of Douglas. The uterus appeared normal in size and morphology. The right ovary was unremarkable. The right fallopian tube was substantially dilated along approximately two-thirds of its length and appeared violaceous, with blood clots present near the fimbrial end (Figure 4). The left adnexa were normal. Given the overall clinical findings – including a live twin tubal pregnancy, lesion size, degree of tubal damage, and active bleeding – the decision was made to perform a right salpingectomy. Using bipolar coagulation and scissors, the mesosalpinx of the right tube was coagulated and divided, beginning at the ovarian end and proceeding toward the uterine cornu, where the tube was transected. Peritoneal lavage was performed, and a drain was placed in the pouch of Douglas. The excised specimen was submitted for histopathologic examination, which confirmed tubal pregnancy without additional abnormalities.

Because the patient was Rhesus D (RhD)-negative, anti-D immunoglobulin was administered postoperatively. She was discharged on postoperative day 1 with a β-hCG level of 1962 mIU/mL and returned for follow-up 1 week after surgery. Gynecologic examination was unremarkable, and the β-hCG level had declined to 237 mIU/mL. The patient’s characteristics are summarized in Table 1.

Discussion

Recognized risk factors for extrauterine pregnancy include pelvic inflammatory disease, a history of ectopic pregnancy, prior tubal surgery, use of fertility medications or an intrauterine device, assisted reproductive technology, congenital uterine anomalies, advanced maternal age, and tobacco use [4,13].

Ultrasound is the primary imaging modality for evaluating women with suspected early pregnancy complications, including ectopic pregnancy, because clinical history and physical examination alone have limited sensitivity and are insufficient to establish a definitive diagnosis [1,14]. Confirmation of ectopic pregnancy should also include measurement of serum β-hCG levels [14]. The discriminatory zone, defined as a serum β-hCG concentration of 1500–3000 mIU/mL, represents the threshold at which an intrauterine gestational sac is expected to be visualized on transvaginal ultrasonography [15]. Failure to demonstrate an intrauterine pregnancy at β-hCG levels exceeding this threshold is highly suggestive of either early pregnancy loss or ectopic pregnancy [16].

Emergency laparoscopy is the diagnostic and therapeutic method of choice in cases of suspected acute or life-threatening bleeding due to ectopic pregnancy. The procedure should be performed without delay and without awaiting additional diagnostic investigations in patients with a positive pregnancy test who present with the clinical triad of unexplained lower abdominal pain, hemodynamic instability, and low hemoglobin levels [14]. In asymptomatic women who do not require immediate intervention, expectant management, medical treatment, and surgical management are potential options, depending on the clinical scenario and the patient’s preferences, particularly her reproductive plans [14,17,18].

Live ectopic pregnancies represent a minority of all ectopic pregnancies; however, their potential for severe complications is high, and they may be considered a distinct clinical entity [1]. Risk factors for twin ectopic pregnancy are similar to those for singleton ectopic pregnancy. The presence of multiple embryos – particularly after assisted reproductive technology [19] – and a history of sexually transmitted infections [20] serve as more specific contributors. In the absence of dedicated guidelines for twin ectopic pregnancies, management should follow principles established for singleton ectopic pregnancy. A live ectopic pregnancy constitutes a clear contraindication to both expectant management and medical treatment; therefore, surgery is the only appropriate option [14]. Laparoscopy remains the treatment of choice, and in most reported cases of live twin ectopic pregnancy, this approach has been used. Laparoscopic salpingectomy is most commonly performed due to its technical simplicity, more complete removal of trophoblastic tissue, and lower risk of postoperative complications. A review of the literature identified only 1 case managed via methotrexate-mediated, ultrasound-guided fetal reduction [21]; laparoscopic salpingectomy was performed in all other reported cases.

The choice between salpingectomy and a tube-preserving approach should be guided by the clinical context, the patient’s history, and her individual preferences [14]. In patients who wish to preserve fertility, a tube-conserving procedure – namely salpingotomy with removal of the ectopic pregnancy – should be considered when feasible. Patients must be counseled regarding the risk of recurrent ipsilateral ectopic pregnancy after tube-conserving surgery. In selected cases, ampullary pregnancies may be gently expressed through the fimbrial end (“milking” of the tube) by digital expression, suction, or aquadissection [22]. However, this technique is associated with increased risks of intraoperative bleeding, persistent trophoblastic tissue, and tubal injury, as well as a recurrent ectopic pregnancy rate of up to 33% [23]. Considering the potentially higher risk of persistent trophoblastic tissue in twin ectopic pregnancies – related to larger lesion size and greater trophoblastic mass – salpingectomy appears to be the preferred treatment option.

Given the rarity of twin ectopic pregnancies and absence of standardized management protocols, future research should focus on developing evidence-based guidelines specifically tailored to these cases. Additional studies are required to better define optimal diagnostic approaches, treatment strategies, and follow-up protocols. Such efforts would help address current knowledge gaps and improve clinical decision-making and patient outcomes.

Conclusions

Live ectopic pregnancies are rare but carry substantial risks. The presence of embryonic cardiac activity precludes both expectant and medical management. Twin ectopic pregnancies are exceedingly uncommon, such that few cases have been reported. Their risk factors mirror those of singleton ectopic pregnancies, although assisted reproductive technology and prior sexually transmitted infections may play a more specific role. In these cases, surgery – most commonly laparoscopic salpingectomy – remains the only safe and appropriate option. Early recognition and prompt surgical intervention are essential to prevent life-threatening complications and ensure optimal outcomes. Given the increasing number of women undergoing assisted reproductive technology, the management of live twin ectopic pregnancies should be incorporated into clinical guidelines and recommendations.