Delayed management of an early-diagnosed primary omental pregnancy complicated by ileal placental invasion and haemorrhagic shock: a case report

¹Department of Obstetrics, Gynaecology and Maternal Prevention, Centre Hospitalier d’Essos, Yaoundé, Cameroon, ²Department of Obstetrics and Gynaecology, Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaoundé, Cameroon

^&Corresponding author
Sophie Danielle Abenelang Bilongo, Department of Obstetrics, Gynaecology and Maternal Prevention, Centre Hospitalier d’Essos, Yaoundé, Cameroon

Introduction    

Abdominal pregnancy is one of the rarest and most hazardous forms of ectopic pregnancy, in which implantation occurs within the peritoneal cavity outside the uterus, fallopian tubes, and ovaries, accounting for approximately 1% of all ectopic pregnancies. Primary omental pregnancy is an exceptionally rare subtype associated with a high risk of catastrophic haemorrhage because placental implantation may involve highly vascular intra-abdominal structures [1]. Prompt surgical management is recommended once the diagnosis is established to reduce maternal morbidity and mortality.

Although poor maternal outcomes are commonly attributed to delayed diagnosis, timely diagnosis alone may not be sufficient when access to definitive treatment is limited. We report the case of a 23-year-old primigravida with a primary omental pregnancy diagnosed during the first trimester but managed only at 17+2 weeks' gestation because, although she accepted the specialists' recommendation for surgery, financial constraints delayed access to definitive treatment. The lack of timely management resulted in progression to massive hemoperitoneum, haemorrhagic shock, and placental invasion of the ileum, ultimately requiring emergency multidisciplinary surgical management. This case highlights the importance of ensuring that early diagnosis is accompanied by timely access to definitive treatment, particularly in resource-limited settings.

Patient and observation     

Patient information: a 23-year-old primigravida with no significant past medical or surgical history and no recognized risk factors for ectopic pregnancy presented to the emergency department with severe lower abdominal pain of 24 hours' duration associated with progressive asthenia. She reported taking ibuprofen without symptomatic relief before seeking medical attention and denied vaginal bleeding, fever, gastrointestinal, or urinary symptoms. The patient's socioeconomic circumstances were marked by significant financial hardship, which limited her ability to access the recommended surgical treatment. Despite repeated counselling and her agreement to undergo urgent surgical management, financial constraints prevented timely access to surgery. She was subsequently lost to follow-up and presented to our institution at 17+2 weeks' gestation with acute clinical deterioration.

Timeline: the abdominal pregnancy was first diagnosed by ultrasonography at 7 weeks of gestation and confirmed at 11+5 weeks. A third ultrasound performed at 13+3 weeks further confirmed the diagnosis. At 17+2 weeks, the patient presented with acute abdominal pain and haemorrhagic shock. Emergency laparotomy and partial omentectomy were performed within one hour of admission, followed by postoperative multidose methotrexate therapy. Serum β-hCG levels became undetectable one month later, and complete clinical and ultrasonographic resolution was documented at three months.

Clinical findings: on admission to the obstetrics and gynaecology department, the patient appeared acutely ill and pale. Her temperature was 36.8°C, heart rate 122 beats/min, blood pressure 108/78 mmHg, respiratory rate 20 breaths/min, and oxygen saturation 98% on room air. Physical examination revealed pale conjunctivae, cold extremities, and diffuse abdominal tenderness with involuntary guarding.

Laboratory investigations: hemoglobin was 9.4 g/dL, hematocrit 28%, white blood cell count (WBC) 5.5 x 10⁹/L, platelet count 314 × 10⁹/L, and blood group AB Rh-positive.

Coagulation profile: prothrombin time (PT) was 13.1 s and activated partial thromboplastin time (aPTT) 37.8 s.

Gynaecological examination: vaginal examination revealed cervical motion tenderness without vaginal bleeding. Bimanual pelvic examination could not be completed because of severe abdominal pain and guarding.

Diagnostic assessment and challenges: review of the patient's previous medical records confirmed that the diagnosis of abdominal pregnancy had already been established by three independent ultrasonographic examinations performed at 7, 11+5, and 13+3 weeks of gestation. Repeat urgent transabdominal and transvaginal ultrasonography on admission demonstrated a viable abdominal pregnancy corresponding to 17+2 weeks of gestation, with no gestational sac identified within the uterine cavity. A large amount of free anechoic-hypoechoic fluid was present in the pouch of Douglas, highly suggestive of hemoperitoneum. The endometrium was homogeneous and measured 13 mm in thickness.

The patient's clinical condition deteriorated progressively. Based on the clinical presentation and ultrasound findings, a diagnosis of advanced abdominal pregnancy complicated by massive hemoperitoneum and haemorrhagic shock was established. Given the patient's hemodynamic instability and the indication for emergency surgery, no further diagnostic investigations were performed.

Therapeutic intervention: following initial resuscitation with intravenous crystalloids and one unit of packed red blood cells, the patient underwent emergency exploratory laparotomy. Approximately 1500 mL of blood with blood clots were evacuated from the peritoneal cavity. Exploration revealed a pregnancy implanted entirely within the greater omentum. The gestational sac was opened, and a live fetus measuring approximately 14 cm crown-rump length was delivered but did not survive beyond the immediate postoperative period (Figure 1). Inspection of the implantation site demonstrated placental attachment to the omentum with extension into the ileal wall, where active bleeding was observed. The uterus was enlarged but intact, whereas both fallopian tubes and ovaries appeared macroscopically normal, confirming the diagnosis of primary omental pregnancy.

A multidisciplinary approach involving the obstetrics and gynaecology and general surgery teams was adopted. Partial omentectomy was performed to remove the omental implantation and achieve haemostasis. Fetal cardiac activity persisted for approximately 20 min after delivery before ceasing (Figure 2). Approximately 5% of the placental tissue invading the ileal wall was deliberately left in situ because complete excision was considered to pose an unacceptable risk of bowel injury and catastrophic haemorrhage (Figure 3). Postoperatively, the patient received broad-spectrum antibiotics, analgesics, blood products as required, and systemic multidose methotrexate therapy to promote involution of the retained placental tissue. Serial serum β-hCG measurements were scheduled to monitor treatment response.

Follow-up and outcomes: the immediate postoperative course was initially uneventful. However, recovery was subsequently complicated by delayed wound healing and suboptimal adherence to the prescribed postoperative treatment because of persistent financial barriers. The patient was unable to obtain all prescribed medications and intermittently reduced the recommended dosages to prolong their use. Following intervention by the hospital's social services, access to the required medications was secured, allowing completion of systemic multidose methotrexate therapy and appropriate postoperative care. Serial serum β-hCG measurements performed during the first postoperative month demonstrated progressive decline, reaching undetectable levels within one month. The patient was discharged on postoperative day 7 in good general condition with outpatient follow-up. She remained clinically stable throughout follow-up, and pelvic ultrasonography performed three months after surgery demonstrated complete resolution of the retained placental tissue.

Patient perspective: the patient expressed gratitude for the care she received and reflected that, had she been able to undergo surgery earlier, her pregnancy might have had a different outcome. She hopes her experience will encourage improvements in access to emergency obstetric care for women facing financial hardship.

Informed consent: written informed consent was obtained from the patient for publication of this case report and accompanying images. No personal identifying information has been disclosed.

Discussion     

Published reports of primary omental pregnancy remain exceptionally scarce. Unlike secondary abdominal pregnancy, which results from tubal rupture or abortion followed by secondary peritoneal implantation, primary abdominal pregnancy arises from direct implantation within the peritoneal cavity [2]. Its estimated incidence ranges from 1 in 10,000 to 1 in 30,000 pregnancies [1]. In the present case, the normal appearance of the uterus, fallopian tubes, and ovaries at laparotomy fulfilled the operative (Studdiford) criteria for primary abdominal pregnancy. Comparison with some previously published cases of primary omental pregnancy (Table 1) further highlights the distinctive features of the present case [3-7].

The most remarkable aspect of this case was not only the omental implantation with secondary ileal placental invasion, but also the progression of the pregnancy into the second trimester despite diagnosis during the first trimester. Delayed diagnosis is widely recognized as one of the major contributors to adverse maternal outcomes in abdominal pregnancy [8]. In contrast, our patient underwent repeated ultrasonographic confirmation and received appropriate specialist counselling shortly after diagnosis. Nevertheless, although she agreed to the recommended surgical management, definitive treatment was deferred because financial constraints prevented timely access to surgery. The prolonged interval between diagnosis and surgery allowed continued fetal development, progressive placental invasion of the ileum, and ultimately massive hemoperitoneum with haemorrhagic shock. The outcome in this case reinforces that recognition of a rare obstetric condition must be coupled with rapid access to appropriate intervention to minimize maternal complications.

Late referral also substantially increased the complexity of surgical management. Abdominal placental implantation may involve adjacent organs and blood vessels, considerably increasing the risk of massive haemorrhage and visceral injury [1]. In our patient, ileal involvement required a multidisciplinary approach involving obstetricians and general surgeons. Current evidence supports individualized placental management based on the implantation site, degree of placental penetration, and anticipated haemorrhagic risk [8]. Accordingly, the omental component of the placenta was excised, whereas the small residual portion invading the ileal wall was intentionally left in situ because complete removal posed an unacceptable risk of bowel injury and uncontrollable haemorrhage. Although the use of methotrexate following abdominal pregnancy remains controversial because of concerns regarding rapid placental necrosis and secondary infection, it may be considered in carefully selected patients with intentionally retained placental tissue under close follow-up [9]. In our patient, postoperative multidose methotrexate was associated with progressive decline of serum β-hCG to undetectable levels and complete ultrasonographic resolution of the retained placental tissue. Compared with previously published reports, this case is distinguished by the combination of early ultrasonographic diagnosis, prolonged progression into the second trimester due to delayed access to treatment, ileal placental invasion, and successful conservative management of retained placental tissue.

Beyond its clinical rarity, it also highlights an important public health challenge. Abdominal pregnancy remains associated with maternal mortality rates ranging from 0.5% to 18%, approximately 7.7 times higher than other ectopic pregnancies and 90 times higher than intrauterine pregnancies, while fetal mortality ranges from 45% to 90% [1]. Our patient's course illustrates that delayed access to definitive treatment, even after an established diagnosis, may represent an important and potentially preventable contributor to these poor outcomes. In many low-resource settings, financial hardship, out-of-pocket healthcare costs, and limited access to specialist surgical care continue to delay emergency obstetric interventions, allowing progression to life-threatening complications [10]. Whenever feasible, patients diagnosed with abdominal pregnancy should be referred promptly to centres with multidisciplinary surgical expertise. Close follow-up should be maintained when immediate surgery cannot be performed, and early mobilization of social support or financial assistance mechanisms may facilitate timely definitive treatment. This case emphasizes that improving outcomes in abdominal pregnancy requires more than early diagnosis; it also depends on timely referral, multidisciplinary management, and reducing barriers to life-saving surgical care, particularly in resource-limited settings. Although this report describes a single patient and cannot establish causality between delayed access to surgery and adverse outcomes, it illustrates how financial barriers may contribute to preventable maternal morbidity despite early diagnosis.

Conclusion     

Primary omental pregnancy is a rare but life-threatening condition requiring prompt multidisciplinary management. This case highlights that early diagnosis alone is insufficient to prevent severe maternal morbidity when timely access to definitive treatment is limited. Prompt referral and reduction of financial barriers to emergency obstetric care are essential to improve maternal outcomes in resource-limited settings.

Competing interests     

The authors declare no competing interests.

Authors' contributions     

Sophie Danielle Abenelang Bilongo conceived, drafted, and critically revised the manuscript. Daniel Tarh Ketchen edited and made some modifications. All authors have read and approved the final version of this manuscript.

Table and figures     

Table 1: comparison of the present case with previously reported cases of primary omental pregnancy

Figure 1: live fetus delivered during exploratory laparotomy for primary omental pregnancy at 17+2 days of gestation

Figure 2: surgical specimen showing (1) the fetus, (2) the umbilical cord, and (3) the placenta attached to a portion of the greater omentum

Figure 3: intraoperative assessment of the placental invasion following a multidisciplinary evaluation, residual placental implantation on the ileum was left in situ because of the high risk of bowel injury and haemorrhage

References