AFJOG

REVIEW African Journal of Obstetrics and Gynaecology | Volume 2 | Issue 2 | 2024 | Full-term abdominal ectopic pregnancy INTRODUCTION The term ectopic pregnancy (EP), also known as extrauterine pregnancy, is derived from the Greek word 'ektopos' which means out of place. It is defined as the implantation of a fertilized egg anywhere outside the endometrial cavity of the uterus. An estimated 1% of all pregnancies are ectopic pregnancies, and 95% of these ectopic pregnancies occur in the fallopian tubes. The remaining 5% occur at other sites such as the ovaries, cervix, caesarean section scar, within the broad ligament and the peritoneal cavity [1,2] . When a fertilized ovum implants within the peritoneal cavity but outside the female reproductive organs (uterus, tubes, ovaries) and broad ligament, it is referred to as an abdominal pregnancy (AP), which is a very rare condition that represents 0.6% to 1% of EP. The incidence of AP differs in various publications and is estimated to be between 1:10,000 and 1:30,000 of EP [2,3,4] . Estimated maternal mortality in women with AP is 0.5% to18%, and perinatal mortality is as high as 40% to 95% [5] . The total maternal mortality in AP is estimated to be 7.7 times higher than that of tubal EP, and 90 times that of an intrauterine pregnancy [1,6] . AP can be classified as primary or secondary AP. When a fertilized egg is directly implanted in the peritoneal cavity, it is called a primary AP. Studdiford's criteria for its diagnosis include normal tubes and ovaries, absence of utero-placental fistula, and the pregnancy must be attached exclusively to the peritoneal surface and be early enough (<12 weeks) to exclude the possibility of secondary implantation [5] . Secondary AP refers to a pregnancy that was initially located in the tubes, or less commonly in the uterus or ovaries and is reimplanted in the peritoneal cavity after tubal abortion or clinically silent rupture of the tube or hysterotomy scar at very early gestation where the embryo and fetus continue to grow [4, 7, 8] . AP can also be classified as early and advanced abdominal pregnancy depending on gestational age. The AP before 20 weeks is called early abdominal pregnancy (EAP) and AP that progresses beyond 20weeks of gestation is known as advanced abdominal pregnancy (AAP) and it is the only EP where the fetus has the potential to survive as a neonate. The diagnosis of AP is challenging as symptoms are nonspecific. A high index of suspicion and thorough clinical and ultrasound examinations can assist in making the diagnosis [5,9] . ABDOMINALPREGNANCY AP is a rare condition and it represents approximately 1% of EP. However, most of the cases reported in the literature are from low- or middle-income countries where women of low socioeconomic class often book late in the second or third trimester. Since the patient may be asymptomatic or the symptoms that occur are nonspecific such as abdominal pain, suprapubic pain, mild vaginal bleeding or spotting in the first or second trimester or gastrointestinal symptoms, it is often difficult to clinically diagnose AP [5,10] . About half of the cases are missed during the antenatal period due to the difficulty in diagnosis and many cases are diagnosed rather incidentally during surgery. The obstetrician should have a high index of suspicion if the patient complains of persistent abdominal pain, painful fetal movements, and on examination fetal parts that are easily palpable with an abnormal fetal lie or presentation. Furthermore, if at the vaginal examination the cervix is displaced, or there is failed induction of labour in the presence of one or more of the above-mentioned clinical findings, the diagnosis of AP should be considered [1] . DIAGNOSIS An early pregnancy antenatal trans-vaginal ultrasound is an important tool for diagnosis of AP in the first trimester, so that early management can help avoid the serious complications associated with AAP. Ultrasound features include an extrauterine gestational sac or fetus separate from a nongravid uterus and adnexa, abnormal presentation or lie of the fetus, lack of myometrial tissue around the fetus, and reduced or absent amniotic fluid. Oligohydramnios or absence of amniotic fluid along with fluid in the pouch of Douglas suggests intra- abdominal rupture of membranes [11] . Ultrasound has good sensitivity to diagnose AP in experienced hands. However, when ultrasound examination findings are uncertain, magnetic resonance imaging (MRI) is recommended, which has a high level of precision in diagnosing AP as well as locating the placental attachments to adjacent abdominal organs and tissues [1,9,11,12] . The optimal time to locate the gestational sac is during the first trimester ultrasound examination. The late ultrasound examination performed in the third trimester by inexperienced practitioners can result in missing the diagnosis of AP. Furthermore, the sensitivity of ultrasound to diagnose AP in the third trimester is reduced even in experienced hands. PATHOPHYSIOLOGY Most cases of AP occur after tubal EP abortion or silent rupture of a tubal EP. Some of the risk factors for AP are the same as tubal EP, such as pelvic inflammatory disease, history of tubal K Baloyi, AMisra, R Hlengani, T Malebana, M Mashilo Department of Obstetrics and Gynaecology, Pietersburg Provincial Hospital, University of Limpopo, South Africa CORRESPONDENCE: K Baloyi| Email: baloyikaizer@gmail.com Abdominal Pregnancy ABSTRACT Abdominal pregnancy is a rare form of ectopic pregnancy, in which implantation occurs in the peritoneal cavity. It accounts for about 1% of ectopic pregnancies. The diagnosis is often missed if an ultrasound examination is not performed in the early stages of pregnancy or done by an inexperienced professional. Abdominal pregnancies are at high risk of massive haemorrhage due to abnormal placentation, and rarely go to term gestation with a live fetus. Abdominal pregnancy has a high rate of missed diagnosis because there are no specific clinical signs and symptoms to diagnose, and that explains why some of the abdominal pregnancies advance to term gestation. However, if diagnosed accidentally before or during surgery, the patient should be treated in the tertiary setting due to associated life-threatening complications that can be better managed by specialist care. Keywords: Abdominal pregnancy; Advanced abdominal pregnancy African Journal of Obstetrics and Gynaecology | Volume 2 | Issue 2 | 2024 | 11