**2.2 Diagnosis**

A high index of suspicion for this rare and serious condition, complemented by often nonspecific findings in the clinical history and physical examination may lead to a timely correct diagnosis. Recurrent abdominal pain and tenderness, a relatively mobile abdominal mass in an amenorrheic woman of reproductive age, painful fetal movements in the upper abdomen associated with a persistently abnormal lie, fetal heart sounds localized in the upper epigastrium, should raise the possibility of an AP and be followed by an ultrasound examination (5). In early pregnancy the diagnosis of AP might be missed by failure to obtain an image demonstrating continuity of the vagina, cervix and uterus with its pregnancy contents (1). Four ultrasound criteria have been suggested to support the diagnosis of AP: (1) absence of an intrauterine gestational sac, (2) absence of both an evident dilated tube and a complex adnexal mass, (3) a gestational sac surrounded by loops of bowel and separated

Term Extra-Uterine Pregnancy 165

(19). Ultrasound evaluation is of benefit in the follow-up of placental involution after

Although still rare, the increasing incidence of AP in both developed and especially developing countries mandates awareness of this diagnosis, particularly in pregnant or

Both cervical and cervico-isthmic pregnancies are rare, life-threatening forms of ectopic gestations. The former is reported to have an estimated incidence of one in 2,500 to one in 18,000 pregnancies, and represents less than 1% of all ectopic gestations (1). A cervical pregnancy (CP) results from the implantation and growth of a blastocyst within the mucosa of the endocervical canal and is located completely within the cervical canal, with no placental tissue above the internal cervical os (2, 3). Currently CP are diagnosed by transvaginal ultrasound early in the first trimester of pregnancy and terminated by conservative, fertility sparing medical and/or surgical management. Most cases are not reported and therefore the exact incidence of CP is unclear. A CP is never viable and is unlikely to progress past 20 weeks of gestation. Previous reports of CP ending in live births are now thought to have been cervico-isthmic pregnancies (CIP) (3, 4, 5 ). In a CIP the gestational sac implants in the uterine isthmus, between the histologic and anatomic cervical os, and subsequently extends into the lower uterine segment (3, 4). The process of incorporation of the lower uterine segment into the gestational cavity occurs from the cervix upward rather than from the uterine cavity downward, as it happens in a normally implanted pregnancy (4). CIP are even more important clinically because they can grow to advanced gestational age and have significant perinatal complications. The growing gestational sac causes premature cervical effacement and dilatation which result in preterm premature rupture of the amniotic membranes and preterm delivery (6). Trophoblastic invasion of the endocervical and isthmic mucosa and stroma result in placenta accreta, placenta increta or placenta percreta and explain the massive hemorrhage at attempted placental removal (6, 7). Since 1980, when the term CIP was coined (3), the English language literature reported thirteen CIP exceeding 24 weeks, which is considered as the gestational

delivery of an advanced AP (14).

**3. Term cervico-isthmic pregnancy** 

postpartum women presenting with abdominal pain (11).

age of neonatal viability (3, 4, 6 – 16). Table 1 summarizes these reports.

diagnostic challenge of this entity (3, 8, 10, 13, 15).

Diagnostic algorithms and clinical prediction rules for CIP are difficult to validate because of the limited number of reported cases. In five of the thirteen women (38.5%) with advanced CIPs, the correct diagnosis was made at the time of delivery, underscoring the

Several associated clinical signs noted historically should be heeded for a timely diagnosis of CIP. In case of painless vaginal bleeding occurring after 20 weeks of gestation, in a nulliparous woman in the fourth or fifth decade of life, CIP should be considered in the differential diagnosis. Painless vaginal bleeding was the presenting clinical sign in six women diagnosed with CIP reaching fetal viability (46%) (6, 7, 9, 11, 14, 16). Maternal age

**2.4 Conclusion** 

**3.1 Introduction** 

**3.2 Diagnosis** 

by peritoneum, (4) a wide mobility similar to fluctuation of the sac particularly evident with pressure of the transvaginal probe toward the posterior cul-de-sac (6). Characteristic sonographic features in an advanced AP are: fetal parts adjacent to the mother's abdominal content, absence of the uterine wall between the maternal urinary bladder and the fetus, a pseudo-placenta previa appearance, oligohydramnios (4). Despite the availability of prenatal ultrasound in developed countries, AP continues to be reported at a late gestation underscoring the difficulty in diagnosing this entity as well as the failure to observe basic ultrasound techniques (1). This would explain a 50-90% diagnostic failure rate and the often unexpected diagnosis of AP during elective Caesarean Sections performed for fetal malpresentation or low-lying placenta (7, 8, 9, 10). Puerperal presentations of a living heterotopic AP have been described, thus underscoring the diagnostic challenge represented by this rare entity (11, 12). In undiagnosed advanced AP cardiovascular shock due to intraabdominal bleeding and sudden death are more ominous presentations (13). MRI offers, apart from diagnostic reassurance, no additional information to ultrasound assessment and is therefore, as an adjunct imaging modality, not central to the diagnosis of advanced AP (1, 14).

#### **2.3 Management of AP**

Management of an AP requires a careful initial evaluation of the fetus in terms of gestational age, the presence of associated fetal anomalies, the amount of amniotic fluid (as a determinant of fetal pressure deformities and pulmonary hypoplasia)(4, 15). This is best accomplished at a referral center with adequate resources: medical imaging and interventional radiology service, blood bank, intensive care unit as well as a surgical team capable of handling possible bowel, vascular, genitourinary complications that might arise. Because of the risk of sudden intra-abdominal haemorrhage due to either placental abruption or vascular invasion, most advise surgical intervention as soon as the diagnosis of AP is confirmed and regardless of the fetal condition (4). A conservative approach may be considered and delivery delayed until fetal maturity is reached, if the gestational age exceeds 20 weeks and the following prerequisites are met: absence of fetal malformations, adequate amniotic fluid volume, absence of maternal medical contraindications, placental implantation site not in the proximity of major vessels, liver or spleen, continuous maternal hospitalization in an appropriate facility, fetal surveillance with daily heartrate monitoring and serial ultrasound assessments, and informed consent from the patient (4).

In the absence of complications, delivery of an advanced AP can be planned for 34 weeks' gestation. Careful preoperative preparations should include: an adequate supply of blood and blood products, appropriate intravenous infusion access, availability of cell-saver and MAST (Military Antishock Trouser) Suit, a multidisciplinary surgical team (4, 7, 10, 15). A midline vertical skin incision should be employed for entry into the abdominal cavity as adequate exposure is paramount. Bleeding could be prevented by incising the amniotic sac in an avascular area, avoiding the proximity of the placenta, as well as by careful removal of the fetus without disturbing the placenta and surrounding membranes (4, 15). Placental management following an advanced AP has shifted towards a non-surgical approach, leaving this organ in situ (16, 17). Although this approach has decreased the high maternal morbidity and mortality associated with attempted surgical removal, leaving the placenta in situ has also potential risks for the mother: a prolonged resorption period, haemorrhage, bowel obstruction and peritonitis (18). The use of methotrexate to accelerate absorption of a retained placenta remains controversial due to the potential severe associated complications (19). Ultrasound evaluation is of benefit in the follow-up of placental involution after delivery of an advanced AP (14).

#### **2.4 Conclusion**

164 Ectopic Pregnancy – Modern Diagnosis and Management

by peritoneum, (4) a wide mobility similar to fluctuation of the sac particularly evident with pressure of the transvaginal probe toward the posterior cul-de-sac (6). Characteristic sonographic features in an advanced AP are: fetal parts adjacent to the mother's abdominal content, absence of the uterine wall between the maternal urinary bladder and the fetus, a pseudo-placenta previa appearance, oligohydramnios (4). Despite the availability of prenatal ultrasound in developed countries, AP continues to be reported at a late gestation underscoring the difficulty in diagnosing this entity as well as the failure to observe basic ultrasound techniques (1). This would explain a 50-90% diagnostic failure rate and the often unexpected diagnosis of AP during elective Caesarean Sections performed for fetal malpresentation or low-lying placenta (7, 8, 9, 10). Puerperal presentations of a living heterotopic AP have been described, thus underscoring the diagnostic challenge represented by this rare entity (11, 12). In undiagnosed advanced AP cardiovascular shock due to intraabdominal bleeding and sudden death are more ominous presentations (13). MRI offers, apart from diagnostic reassurance, no additional information to ultrasound assessment and is therefore, as an adjunct imaging modality, not central to the diagnosis of advanced AP (1, 14).

Management of an AP requires a careful initial evaluation of the fetus in terms of gestational age, the presence of associated fetal anomalies, the amount of amniotic fluid (as a determinant of fetal pressure deformities and pulmonary hypoplasia)(4, 15). This is best accomplished at a referral center with adequate resources: medical imaging and interventional radiology service, blood bank, intensive care unit as well as a surgical team capable of handling possible bowel, vascular, genitourinary complications that might arise. Because of the risk of sudden intra-abdominal haemorrhage due to either placental abruption or vascular invasion, most advise surgical intervention as soon as the diagnosis of AP is confirmed and regardless of the fetal condition (4). A conservative approach may be considered and delivery delayed until fetal maturity is reached, if the gestational age exceeds 20 weeks and the following prerequisites are met: absence of fetal malformations, adequate amniotic fluid volume, absence of maternal medical contraindications, placental implantation site not in the proximity of major vessels, liver or spleen, continuous maternal hospitalization in an appropriate facility, fetal surveillance with daily heartrate monitoring

and serial ultrasound assessments, and informed consent from the patient (4).

In the absence of complications, delivery of an advanced AP can be planned for 34 weeks' gestation. Careful preoperative preparations should include: an adequate supply of blood and blood products, appropriate intravenous infusion access, availability of cell-saver and MAST (Military Antishock Trouser) Suit, a multidisciplinary surgical team (4, 7, 10, 15). A midline vertical skin incision should be employed for entry into the abdominal cavity as adequate exposure is paramount. Bleeding could be prevented by incising the amniotic sac in an avascular area, avoiding the proximity of the placenta, as well as by careful removal of the fetus without disturbing the placenta and surrounding membranes (4, 15). Placental management following an advanced AP has shifted towards a non-surgical approach, leaving this organ in situ (16, 17). Although this approach has decreased the high maternal morbidity and mortality associated with attempted surgical removal, leaving the placenta in situ has also potential risks for the mother: a prolonged resorption period, haemorrhage, bowel obstruction and peritonitis (18). The use of methotrexate to accelerate absorption of a retained placenta remains controversial due to the potential severe associated complications

**2.3 Management of AP** 

Although still rare, the increasing incidence of AP in both developed and especially developing countries mandates awareness of this diagnosis, particularly in pregnant or postpartum women presenting with abdominal pain (11).
