Abdominal pregnancy (AP), in which the fetus grows outside the female reproductive tract and within the peritoneum, is a very rare type of ectopic pregnancy (EP), accounting for 1% of all EPs [1]. The incidence rate ranges considerably from study to study (1 in 400-50,000 live births), but it must be noted that abdominal pregnancy is the only type of EP that can end as a successful delivery of a full-term newborn [1] [2] [3]. AP is further divided into primary, when the fertilized ovum directly implants at a site within the peritoneal cavity (bowels, the appendix, spleen, and virtually any other organ, as well as blood vessels, uterine structures, and the omentum, are reported sites), whereas secondary implies implantation of the ovum in the peritoneum after initial adhesion in the reproductive tract and its rupture from various reasons [3] [4]. Regardless of the type, the clinical presentation is comprised of the following symptoms - persistent pain, either in the abdomen or in the suprapubic area, nausea, vomiting, painful movements of the fetus, regular menstruation cycles, vaginal discharge (bloody), and malaise [1] [3] [5] [6]. Because the fetus grows adjacent to several vital organs and blood vessels, both the mother and the fetus are at a much higher risk for complications such as severe and uncontrollable bleeding, maternal bowel obstruction, infections, pulmonary embolism, fistula formation (between the amniotic sac and the intestines) and even disseminated intravascular coagulation [1] [2] [7]. Furthermore, perinatal mortality rates reach as high as 50%, and up to half of all children born after an abdominal pregnancy have some congenital abnormality - torticollis, facial or cranial asymmetry, limb defects or deficits of the central nervous system (CNS) are most common, with oligohydramnios being the presumably pathogenic mechanism [1] [4] [6]. Maternal mortality rates, on the other hand, are somewhat lower (around 12%), but these numbers suggest that an early diagnosis can be life-saving [6].

• Gangrene

  Ahmed Samy El-Agwany, El-sayed El-badawy, Ahmed El-habashy, Hesham El-gammal and Mahmoud Abdelnaby, Secondary Advanced Abdominal Pregnancy after Suspected Ruptured Cornual Pregnancy with Good Maternal Outcome: A Case with Unusual Gangrenous Fetal Toes [doi.org]

• Abdominal Pain

  She suffered from abdominal pain at 16 weeks gestation. At admission, obstetrical examination and transabdominal ultrasonography revealed that it was uterine pregnancy with a single living fetus and oligohydramnios. [ncbi.nlm.nih.gov]

• Abdominal Mass

  This case highlights the importance of excluding pregnancy in any woman of reproductive age with undiagnosed abdominal mass and utero-vaginal prolapse before any manipulation. [ncbi.nlm.nih.gov]

  If she presents with an ABDOMINAL MASS and a SINUS on her abdominal wall (rare), the sinus may be arising in an ectopic pregnancy. Probe it, you may feel fetal bones. Open it with great care not to injure her gut. [web.archive.org]

  On examination, there may be abnormal presentation, easily palpable fetal parts, uneffaced and displaced cervix and palpation of abdominal mass seperate from uterus [8]. High index of suspicion is first step in the diagnosis. [ijcasereportsandimages.com]

  mass, confusing the diagnosis. 2 Computerized tomography (CT) and nuclear magnetic resonance clearly define the pathology and help the diagnosis of adherence and other organs affected, although these are not absolutely necessary. 2,3,4 Some authors suggest [scielo.br]

  Obstet Gynecol Surv 1991, 46: 515-525. 10.1097/00006254-199108000-00003 View Article Google Scholar Ede J, Sobnach S, Castillo F, Bhyat A, Corbett JH: The lithopedion – an unusual cause of an abdominal mass. S Afr J Surg 2011, 49: 140-141. [doi.org]

• Periumbilical Pain

  We attribute the patient’s continuous periumbilical pain at presentation to irritation of the visceral peritoneum somewhere between the jejunum and transverse colon, originating from the placental attachment site. [doi.org]

• Hypertension

  […] and edema and protein in the urine abdominal aortic aneurysm an aneurysm of the abdominal aorta associated with old age and hypertension abdominal aorta a branch of the descending aorta toxaemia of pregnancy an abnormal condition of pregnancy characterized [vocabulary.com]

  Methyldopa and nifedipine were commenced for pregnancy-induced hypertension from 22 weeks of gestation. [doi.org]

  Traditionally, pregnant mommies experience low blood pressure when pregnant; however, it is also likely that women may develop hypertension due to disturbance in vessels or alteration in the secretion of some hormones/neurotransmitters. [newkidscenter.com]

  History and physical examination Symptoms of hepatic rupture include the following: RUQ pain and tenderness Possible history of pregnancy-induced hypertension Hemorrhagic shock Distended abdomen Workup The diagnosis can be confirmed through CT findings [emedicine.medscape.com]

• Cranial Asymmetry

  The most common deformations observed were facial and/or cranial asymmetry and various joint abnormalities. Among the most common malformations were limb deficiency and central nervous system malformations. [ncbi.nlm.nih.gov]

  Furthermore, perinatal mortality rates reach as high as 50%, and up to half of all children born after an abdominal pregnancy have some congenital abnormality - torticollis, facial or cranial asymmetry, limb defects or deficits of the central nervous [symptoma.com]

  Besides slight cranial asymmetry the examination of the newborn baby was unremarkable. The baby’s head circumference was 32cm (5th centile). [doi.org]

• Linea Nigra

  Note linea nigra. Figure 2 Placenta and membranes adherent to loop of bowel (posterior view). The meconium-stained bowel was cleaned with normal saline; no obvious bowel defects were noted. [doi.org]

• Reduced Fetal Movement

  A 22-year-old woman, gravid 3 para 2 was referred to our centre from a district hospital with complaint of generalized abdominal pain and reduced fetal movements. [ncbi.nlm.nih.gov]

  Case presentation A 22-year-old woman, gravid 3 para 2 was referred to our centre from a district hospital with complaint of generalized abdominal pain and reduced fetal movements. [bmcresnotes.biomedcentral.com]

• First Trimester Bleeding

  The prevalence of ectopic pregnancy among women presenting to an emergency department with first trimester bleeding, pain, or both ranges from 1% to 16% [1]. [ncbi.nlm.nih.gov]

• Neglect

  Prior reports have neglected to discuss the implications of leaving the placenta in situ on breastfeeding and lactation. [ncbi.nlm.nih.gov]

  Wu MC, Huang WC, Lin HH, Hsiao SM: Severe intra-abdominal bleeding from neglected omental implantation of ectopic tissue after methotrexate treatment for persistent ectopic pregnancy. Fertil Steril 2011;95:2435.e2431-e2433. [karger.com]

• Amenorrhea

  A 35-year-old, para 2, unbooked, Ethiopian Somali woman presented with amenorrhea of 9 months' duration, abdominal pain, and painful fetal movements of 4 months' duration. [ncbi.nlm.nih.gov]

  The 28-year-old woman in this instance had a history of amenorrhea and pelvic inflammatory disease. She had previously undergone dilatation and curettage, as well as tuboplasty. Fertility treatment was used for her to successfully conceive. [auntminnie.com]

  At 2 months amenorrhea she gave a history of acute abdominal pain associated with spotting per vaginum. Emergency ultrasound done elsewhere at that time confirmed the presence of single live intrauterine gestation. [appliedradiology.com]

Unfortunately, the diagnosis of an abdominal pregnancy is often missed, especially in the first few months of gestation, and studies report that more than 50% of cases were not diagnosed on regular ultrasonographic exams [5] [6] [7]. For this reason, clinical judgment is necessary during diagnostic workup. A high index of suspicion must be present if patients report excessive abdominal pain in the first semester, bleeding, previous pelvic surgery, and a history of infertility, implying that a properly obtained patient history is vital in making a presumptive diagnosis [6]. A meticulous physical examination is equally important, as relatively easy palpation of fetal limbs and an abnormal lie, as well as abdominal or suprapubic tenderness, are important features of AP [1] [6]. Once clinical criteria have been solidified, imaging studies are used for confirmation. Standard fetal ultrasonography, however, may not reveal any pathological findings unless the physician patiently looks for the uterus and reveals an empty uterine cavity [1]. Insertion of a balloon catheter into the uterus is often recommended to confirm the absence of the fetus inside the uterus [1] [6]. A definite diagnosis can be made by performing more advanced imaging studies, either computed tomography (CT) or magnetic resonance imaging (MRI) [2] [3]. Laboratory studies are usually normal for a regular pregnancy, showing high levels of human chorionic gonadotropin (βhCG) and/or serum alpha-fetoprotein (AFP) [1].

• Ovarian Mass

  Pregnant women are predisposed to adnexal torsion, with approximately 20% of adnexal torsions occurring during pregnancy. [6, 89] The condition is associated with an ovarian mass in 50-60% of patients; the mass is most often a dermoid. [emedicine.medscape.com]

1. Bohiltea R, Radoi V, Tufan C, Horhoianu I, Bohiltea C. Abdominal pregnancy - Case presentation. J Med Life. 2015;8(1):49-54.
2. Gudu W, Bekele D. A pre-operatively diagnosed advanced abdominal pregnancy with a surviving neonate: a case report. J Med Case Rep. 2015;9:228.
3. Mengistu Z, Getachew A, Adefris M. Term abdominal pregnancy: a case report. J Med Case Rep. 2015;9:168.
4. Pannu D, Bharti R, Anand H, Sharma M. Term Live Secondary Abdominal Pregnancy: A Case Report. Malays J Med Sci. 2016;23(5):96-99.
5. Nkusu Nunyalulendho D, Einterz EM. Advanced abdominal pregnancy: case report and review of 163 cases reported since 1946. Rural Remote Health. 2008;8(4):1087.
6. Dahab AA, Aburass R, Shawkat W, Babgi R, Essa O, Mujallid RH. Full-term extrauterine abdominal pregnancy: a case report. J Med Case Rep. 2011;5:531.
7. Kun KY, Wong PY, Ho MW, Tai CM, Ng TK. Abdominal pregnancy presenting as a missed abortion at 16 weeks' gestation. Hong Kong Med J. 2000;6(4):425-427.