Hepatic pregnancy managed conservatively

Case history

An 18-year-old woman presented with 19 weeks of amenorrhoea and a palpable mass in the right hyperchondrial region. Ultrasound demonstrated an extra-uterine pregnancy (EUP) with the placenta attached to the under-surface of the liver. Magnetic resonance imaging (MRI) confirmed the findings (Figure 1). The patient was managed as an inpatient and delivered at 34 weeks' gestation because fetal viability had been achieved and an ultrasound demonstrated reduced liquor.

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Figure 1

Magnetic resonance imaging of extra-uterine pregnancy

A laparotomy was performed through a bilateral subcostal incision which met in the midline (rooftop incision). The placenta was found to be attached to the under-surface of the right lobe of the liver encroaching on the porta hepatis. Following the dissection of the bowel off the placental membranes, the amniotic cavity was entered through an avascular area and a healthy 1800 g baby was delivered. No attempt was made to remove the placenta, and bleeding from the membrane edges was controlled by interlocking sutures and the use of gauze packs, which were left in situ and removed after 48 h.

The postpartum period was uneventful and follow-up included ultrasound examinations to evaluate reduction in placenta size. MRI performed 14 months later revealed minimal residual placental tissue.

Conservative management of advanced EUP may be criticized, but the authors have experience of managing such patients expectantly, as long as they are hospitalized in a centre with immediate recourse to emergency interventions (eight cases of EUP have been managed conservatively to fetal viability and none have presented with, or had, intra-abdominal bleeding).

There is no recent data on such patients presenting with intraperitoneal bleeding. Rather, haemorrhage is a major risk factor during surgery.

A crucial question in conservative management is the timing of the delivery. The aim is to achieve fetal viability at 34 weeks' gestation. Our clinical experience indicates that decreased liquor detected on ultrasound and abdominal pain are signs that warrant intervention. In the present case, the patient was asymptomatic, her haemoglobin was normal and the initial ultrasound showed a viable pregnancy with adequate liquor and an absence of congenital abnormalities.

Ultrasonography is now the primary screening modality for ectopic pregnancies, the diagnosis of advanced EUP, the exclusion of fetal anomalies and the monitoring of fetal growth. However, MRI defines the regional anatomy in greater detail and is pivotal in the identification of placental implantation and, therefore, can help in the decision of whether or not to remove the placenta during laparotomy. ^1–3

Surgery in these cases should be performed by experienced health personnel. The rooftop incision used in this case is superior to the midline incision as it provides an optimal view of the operative area. The placenta was left in situ as removal was considered to be hazardous. Bleeding from the placental edges was controlled by suturing and packing. With minimal interference most cases should respond to these manoeuvres, although cases of wedge resection and right hepatic lobectomy have been reported. ⁴ The use of arterial embolization has been reported in cases of morbidly adherent placenta praevia and sub-capsular haematoma of the liver. ⁵ The insertion of arterial catheters just prior to surgery for embolization is an option.

The issue of whether the placenta should be left in situ is contentious. Ileus, peritonitis and abscess formation necessitating a second laparotomy have been reported when the placenta has been left in situ. ⁶ The use of methotrexate to destroy active trophoblastic tissue and thereby facilitate placental involution has been advocated. However, Weinberg and Pauerstein questioned the benefit of chemotherapy in view of the minimal hyperplastic growth of a mature placenta. ⁵ Our patient made a complete recovery within a week; this demonstrates that conservative management of hepatic pregnancy is feasible utilizing newer imaging techniques and approaches such as leaving the placenta in situ.

Discussion

In most cases of hepatic pregnancy, implantation occurs on the lower surface of the right lobe of the liver. The rich vascular supply here makes it a favourable site for fetal growth. ¹ However, hepatic pregnancies tend to abort in the first trimester. This is probably because trophoblastic growth causes disruption of the implantation site, resulting in bleeding which often leads to hypovolaemic shock. ¹ Bleeding after 12 weeks' gestation is rare. ¹