Introduction
Abdominal pregnancy is a rare obstetric entity accounting for 1.4% of ectopic pregnancies and is associated with a high maternal and perinatal morbidity and mortality (1). Defined as an implantation in the peritoneal cavity, exclusive of tubal, ovarian or intraligamentary pregnancy (2), the estimated incidence is 1:10,000 live births (3). Though there are several theories about the pathophysiology, it is broadly classified into two types, namely primary and secondary abdominal pregnancies (4). Risk factors associated with abdominal pregnancies include dilation and curettage, uterine surgeries, history of tubal pregnancy and artificial insemination (5). Studdiford, as early as 1944, proposed the diagnostic criteria of primary abdominal pregnancy which included the following: 1-normal tubes and ovaries, 2- no evidence of uteroperitoneal fistula, 3-pregnancy related solely to the peritoneal surface, and 4- no evidence of secondary implantation following initial primary tubal nidation (6). Allibone et al. defined the ultrasound criteria necessary to diagnose an abdominal pregnancy namely: 1-fetus outside the uterus, 2- failure to see a uterine wall between the fetus and the urinary bladder, 3-close approximation of fetal parts and maternal abdominal wall, 4- eccentric position/attitude of the fetus, 5-placenta outside the uterine cavity, and 6- visualisation of the placenta immediately adjacent to the fetal chest and head with no amniotic fluid (7). Despite defined diagnostic criteria, diagnosis maybe hindered by factors such as an anterior uterine leiomyoma, retroflexed uterus and bicornuate uterus (8). A high index of suspicion is required to diagnose this condition as its clinical features and presenting symptoms vary widely and are non-specific. The more common presenting symptoms include persistent abdominal pain, missed periods, bloody vaginal discharge and vague gastrointestinal symptoms like nausea and vomiting (9). We report a case of secondary abdominal pregnancy at 13 weeks of gestation which was managed surgically.
Objective : To highlight the diagnostic and management dilemmas in secondary abdominal pregnancies
Methods: Case report and literature review on 314 abdominal pregnancies.
Case report:
A 32-year-old primigravida at 13 weeks 5 days of gestation, presented to OBG emergency department, with complaints of generalised pricking abdominal pain and mild chest pain for 5 days which was gradually worsening and spotting per vagina for one day. Five days prior to her presentation at our hospital, she had been admitted at a local hospital with complaints of vomiting and mild abdominal pain. On evaluation there, hemoglobin was 5.7 g/dl and ultrasonography reported a live intrauterine fetus with a crown rump length of 4.57 cm corresponding to 11 weeks of gestation. Fetal heart rate was 175 bpm and maternal ascites along with fluid in the Morrisons pouch was noted. She received two units of packed red cells transfusion and repeat hemoglobin on 6th June 2020 was 9.4 g%. As her symptoms persisted she was referred to our centre, Kasturba Medical College Hospital, Manipal, a tertiary care hospital.
She had an uneventful antenatal course prior to 13 weeks of gestation and no risk factors were identified. On examination she was alert and cooperative, heart rate 92 bpm and blood pressure 110/70 mmHg. Cardiovascular and respiratory system examination were normal. Per abdominal examination revealed abdominal distension, minimal tenderness, no guarding or rigidity and uterus was not palpable. Per speculum examination showed a posterior, long, closed cervix and no evidence of bleeding or clots. Laboratory investigations showed hemoglobin of 8.9 g/dl and the coagulation profile, liver and renal function tests were within normal limits. Admission β-HCG level was 60,614 mIU/ml. Transvaginal sonography revealed an empty uterus measuring 7x4 cm, a left adnexal mass of 7x7 cm and a collection in the Pouch of Douglas measuring approximately 4x3x3 cm. There was evidence of hemoperitoneum with fluid collections in the hepatorenal and splenorenal pouches. An extrauterine live fetus was noted above the uterine fundus, more towards the left side, corresponding to 11 weeks of gestation. There was no communication demonstrable between the fetus/placenta and uterine contour. The couple was counselled in detail about the abdominal pregnancy, the need for surgical removal of the pregnancy and possible complications. A multidisciplinary team including urologist, general and vascular surgeons were on standby and adequate blood products were arranged. After obtaining high risk consent, emergency laparotomy was performed. Intraoperatively, hemoperitoneum was confirmed and a live fetus was lying in the abdominal cavity above the uterine fundus towards the left, just below the abdominal wall. A 500g clot was evacuated. The umbilical cord was ligated and a fetus measuring 6.5x2x2 cm, weighing approximately 20 g was removed (Figure 1). There was evidence of sealed rupture on the left fallopian tube and left uterine cornu; and part of placental tissue was attached to the site. Following a left salpingectomy and uterine cornual repair the bleeding was controlled. On further exploration, bulk of the placental tissue was found attached to the small bowel mesentery and partly to the omentum. With intra operative assistance from surgeons, bulk of the placental tissue was separated. An on-table decision was taken to leave a very minimal amount of placental tissue in situ (<1cm), which was firmly attached to the vascular mesentery in order to avoid massive hemorrhage. Both ovaries and the right fallopian tube appeared normal. Two intra-abdominal drains were left in situ. The total intra operative blood loss was 1370 ml. Intraoperatively she received 3 units of packed red blood cells and 2 units of fresh frozen plasma. Immediate post-operative period was uneventful. Fibrinogen levels and thromboelastography evaluation were normal. She received broad spectrum intravenous antibiotics. Postoperative Hb was 8 g/dl. Both intraabdominal drainage tubes were removed on the 2ndpost- operative day. She recovered well and was discharged after counselling regarding birth spacing and future pregnancies.
Review of literature on 314 abdominal pregnancies:
We performed a literature review of 314 abdominal pregnancies from 1930-2021 using electronic searches in MEDLINE, EMBASE, PubMed, Web of Science and bibliographies of relevant articles. The review was limited to human studies in English. Case reports, case series and systematic reviews were included. Data recorded included site of the ectopic, gestational age at diagnosis, surgical and/or medical management, blood loss and transfusions, maternal morbidity and mortality and fetal outcomes. Descriptive statistics are provided.