Conservative Management of Heterotopic Pregnancy: A Case Report and Review of Literature

Background

Heterotopic pregnancy is the co-occurrence of intrauterine and ectopic pregnancies. This phenomenon is very rare, occurring with a frequency of 1 in 30 000 pregnancies [1]. Risk factors for heterotopic pregnancy are the same as those for ectopic pregnancy and include factors that damage the structure of the fallopian tubes, such as pelvic inflammatory disease, history of infertility treatment, surgeries on the adnexa, a history of operations in the peritoneal cavity, congenital uterine defects, and tobacco smoking [2]. In patients who have undergone assisted reproductive technology (ART), its incidence is estimated at 1 in 100 pregnancies [1]. Due to the increased frequency of ART, we can now expect an increase in the incidence of heterotopic pregnancy. Data from the United States indicate that its incidence in pregnancies conceived with the help of ART was 1.5 per 1000 pregnancies between 1999 and 2022 [3]. The most common abnormal location is the fallopian tube, but other abnormal locations may coexist with an intrauterine pregnancy, such as the cervix [4], caesarean scar [5], ovary [6], or abdominal pregnancy [7]. Due to the rare incidence of this complication, no management standards have been developed anywhere. In the case of a desire to continue a properly located pregnancy, pharmacological therapy with methotrexate is excluded. In this situation, surgical and conservative management under observation are the remaining options. We present a case report of a tubal heterotopic pregnancy, diagnosed at 5 weeks, for which conservative treatment was applied.

Case Report

A 31-year-old woman presented at the Obstetrics and Gynecology Clinic due to a suspected heterotopic pregnancy. The patient was pregnant for the first time, and 8 weeks had elapsed since her last menstrual period. She had a history of irregular menstruation, with cycles of 28–35 days. The pregnancy was conceived naturally, with no history of ectopic pregnancy risk factors. On admission, she reported pain in the right side of the lower abdominal region. Vital signs were within the norm. Blood pressure was 115/65 mmHg, heart rate was 89 bpm, and body temperature was 37°C; no deviations from the norm were found during the general physical examination. On gynecological examination, the body of the uterus was appropriately enlarged in accordance with the gestational age. The left uterine adnexa were without tenderness. The right uterine adnexa were painful during palpation. In the ultrasound examination, an intrauterine single gestational sac of 12 mm and yolk sac of 5 mm were visualized, with normal echogenicity. The bilaminar embryonic disc was not detected in the ultrasound examination. The image corresponded to a pregnancy of 5 weeks and 5 days (Figure 1). In the right uterine adnexa, an enlarged fallopian tube with gestational sac of 12 mm and yolk sac of 5 mm were observed. The echo pattern of the embryo in the fallopian tube was not visible (Figure 2). A trace of free fluid was observed in the rectouterine pouch. A diagnosis of right-sided tubal heterotopic pregnancy was made. Our diagnosis was entirely based on ultrasonography, and we did not employ any other diagnostic methods.

Upon admission, laboratory tests were conducted, revealing the following results: white blood cell count=8550/µl, red blood cell count=4.32 million/µl, hemoglobin concentration=13.2 g/dl, hematocrit=38.2%, platelet count=205 000/µl, and beta human chorionic gonadotropin (beta-hCG)=16 411.00 mIU/ml. The patient’s blood type was also determined.

In the absence of signs indicative of ectopic pregnancy rupture and hemorrhage, the decision was made to implement expectant management, which entailed monitoring the patient in a hospital setting.

During the subsequent days of hospitalization, the patient remained asymptomatic, except for mild abdominal pain. Physical examination revealed no abnormalities, and vital signs were within normal limits. No bleeding from the birth canal was observed. On the fourth day of hospitalization, beta-hCG levels were measured at 30 253.00 mIU/ml. On the seventh day following admission, an embryo with a heartbeat was detected within the uterine cavity (Figure 3). Throughout the hospital stay, a gradual regression of the uterine adnexa was observed, without an increase in the volume of fluid in the rectouterine pouch.

On followup ultrasonography, it was observed that the gestational sac in the right fallopian tube had undergone resorption, resulting in a decreased volume of fluid compared with previous observations. Please refer to the attached figures, which depict the ultrasounds on the 7th and 17th day following admission (Figures 4, 5). As the ectopic pregnancy had regressed, and there were no symptoms of bleeding on ultrasound examination, the patient was discharged on day 20 with a viable pregnancy and evidence of a resorbed tubal pregnancy (Figure 6). The patient received instructions for maintaining a well-balanced lifestyle and was scheduled for an outpatient followup visit in 7 days. The subsequent course of the pregnancy in the first and second trimesters was uneventful. However, at 34 weeks of gestation, the patient presented to the pathology ward due to premature prelabor rupture of membranes. Initially, conservative management was provided, but after 5 days, uterine contractions began. The patient delivered a preterm live male infant, weighing 2760 grams, via vaginal delivery. The newborn was in good general condition. The postpartum period was uneventful.

Discussion

Heterotopic pregnancy, due to its rare occurrence, can present diagnostic challenges in addition to difficulties in management. These challenges are often related to the appearance of the corpus luteum in the ovary, which may lead to false-positive results. Conversely, an ectopic pregnancy coexisting with an intrauterine pregnancy may be interpreted in ultrasonographic imaging as a hemorrhagic cyst or corpus luteum, resulting in false-negative outcomes [8]. The diagnosis is further complicated by the inability to utilize other standard procedures typically used in ectopic pregnancy diagnosis, such as serial measurements of beta-hCG, progesterone, and uterine curettage. Symptoms of heterotopic pregnancy are often mild and may overlap with typical pain complaints experienced in early pregnancy. Additionally, cervical bleeding, a classic sign of ectopic pregnancy, does not occur in 50% of cases, and is usually absent in heterotopic pregnancy [9]. Ultrasonographic visualization of the presence of a corpus luteum or an embryo in an ectopic compartment greatly facilitates diagnosis.

Before the widespread availability of ultrasonography, the definitive diagnosis was made after opening the peritoneal cavity through laparotomy or laparoscopy [9]. Currently, diagnosis primarily relies on transvaginal ultrasonography [1]. In ambiguous or unclear cases, magnetic resonance imaging may prove helpful [10].

The management of heterotopic pregnancy is not clearly established, due to the low prevalence of this complication. In cases where intrauterine pregnancy is to be maintained, pharmacological treatment is not an option. In this case, surgical management is possible: laparoscopy or laparotomy to perform salpingostomy or salpingotomy. Laparoscopy in pregnancy is associated with potential fetal safety concerns associated with an increase in intra-abdominal pressure, which may result in reduced uterine flow, fetal CO2 absorption, and risk of uterine injury during trocar placement. Some studies suggest that laparoscopy during pregnancy may be associated with an increased risk of fetal loss (pooled relative risk=1.91; 95% CI 1.31–2.77) compared with laparotomy [11], but in the literature, the data are inconsistent [12]. During pregnancy, it is crucial to take into account the risks associated with anesthesia administered to a pregnant patient and the potential impact of medications on the developing fetus when performing medical procedures. Some studies indicate an increased risk of neurological complications, such as hydrocephalus, eye defects, and microcephaly in the fetus in cases of general anesthesia in the first trimester of pregnancy [13,14].

Given the risks involved, it is reasonable to avoid surgical intervention when possible. Current recommendations support conservative management, under close medical observation, of ectopic pregnancy located in the fallopian tube in asymptomatic patients with low beta-hCG values (<2000 mIU/ml) at diagnosis [15]. However, this approach cannot be applied to heterotopic pregnancy due to the presence of an appropriately located trophoblast producing beta-hCG, thereby preventing clear indications. We propose that conservative management may be considered for patients without fluid in the rectouterine pouch, without symptoms, and with no embryonic pulse detected. The literature includes reports of successful conservative management in analogous cases. In a study of 81 cases of heterotopic pregnancy conducted by Li et al [16] from a tertiary referral center, surgery was performed in the majority of cases (64%), while conservative management was applied in the rest of them.

The success rate of the conservative treatment group was 65.52%, and in unsuccessful cases, rescue treatment was applied. In the subgroup analysis, the risk factors for the need for urgent surgical intervention included: size of the lesion in the uterine adnexa >3.5 cm, and gestational age at the moment of diagnosis ≥49 days. In our case, the patient was at low risk due to her gestational age and the size of the lesions in the uterine appendages. Considering the above, conservative management may be applied in an appropriate clinical situation. However, the necessity for observation in hospital conditions should be considered so that surgical intervention can be promptly carried out in the event of emerging indications.

Ultrasound monitoring is essential in this patient population to detect early hemoperitoneum, fetal heart rate in ectopic pregnancy, or rapid growth of the lesion. The presented case highlights the importance of identifying potential issues promptly. In early heterotopic pregnancy located in the fallopian tube, conservative management may be considered to avoid fetal complications associated with surgery and anesthesia. However, the success of this approach hinges on the condition of the patient, in terms of risk factors, and meticulous disease surveillance.

Conclusions

In the case of an ectopic tubal pregnancy, if there are no symptoms of bleeding into the peritoneal cavity, it is possible to adopt a safe conservative approach with strict patient observation. Such an approach allows for the avoidance of potential risks to the mother and fetus associated with the laparoscopy procedure.