**3. Term cervico-isthmic pregnancy**

#### **3.1 Introduction**

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

#### **3.2 Diagnosis**

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

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

Term Extra-Uterine Pregnancy 167

effacement and dilatation and a bulging lower uterine segment. These findings are indicative of two impending perinatal complications of CIP: preterm premature rupture of amniotic membranes and preterm birth. Eight of thirteen CIP (61.5%) delivered prematurely. The gestational age range at delivery was 26 to 34 weeks (4, 6, 8-11, 15, 16). Seven out of eight prematurely born babies survived (87.5%). One neonatal death occurred

Sonography has made early diagnosis of CP and CIP possible and has replaced histologic diagnosis (7). Transvaginal ultrasound has been able to identify CIP at 6 and 7 weeks of gestation in four patients with CIP which reached neonatal viability (4, 6, 7, 12), whereas abdominal ultrasound diagnosed three CIP in mid-trimester (9, 11, 16). Two ultrasound criteria have been proposed to support a diagnosis of CIP and differentiate it from CP: a well-preserved and closed cervical canal, thus ruling out CP and more than half of the uterine cavity above the gestational sac uninvolved by gestational sac implantation (4, 6) Image 3.1. Magnetic Resonance Imaging was useful in distinguishing between CP and

Intra-operatively the diagnosis of CIP is confirmed by the following findings: a small sized, empty uterine corpus and fundus, an abnormally distended and thin walled lower uterine segment, a placenta implanted below the peritoneal reflection of the anterior and posterior surfaces of the uterus, a densely adherent placenta, placental penetration and

The diagnosis of CIP is confirmed by medical imaging and intraoperative findings.

following delivery at 26 weeks of gestation (11).

neovascularization visible under the serosal surface (6, 7, 12).

Image 3.1. Ultrasound of Cervical pregnancy

CIP (17, 18) Image 3.2.

was 35 years or above in seven of the thirteen CIP (54%) and 54% of women had no prior deliveries.

After an ultrasound examination confirmed normal placental localization in a woman with painless vaginal bleeding, speculum examination could reveal premature cervical


Table 1. Summary of CIP reaching neonatal viability (1980-2009)

was 35 years or above in seven of the thirteen CIP (54%) and 54% of women had no prior

After an ultrasound examination confirmed normal placental localization in a woman with painless vaginal bleeding, speculum examination could reveal premature cervical

> Gestational age at diagnosis

David 1980 (3) 28 years; P0 At delivery 40 weeks/alive CS + TAH

Kalakoutis 1985 (8) 43 years; P1 At delivery 28 weeks/alive VD + TAH

Cohen 1985 (9) 36 years; P0 At 25 weeks 27 weeks/alive CS + TAH

Hoffman 1987 (10) 42 years; P2 At delivery 32 weeks/alive CS + TAH

Jelsema 1992 (12) 30 years; P1 5.5 weeks 38 weeks/ alive CS + TAH

Souter 1995 (14) 27 years; P0 21 weeks 28 weeks/ Alive CS + TAH

Strobelt 2001 (4) 41 years; P2 7 weeks 30 weeks /Alive CS + TAH

Mesogitis 2001 (15) 26 years; P0 At delivery 37 weeks /Alive VD + TAH

Honda 2005 (6) 39 years; P0 6 weeks 32 weeks /Alive CS + TAH

Avery 2009 (7) 35 years; P2 5 weeks 6 days 38 weeks /Alive CS + TAH

Table 1. Summary of CIP reaching neonatal viability (1980-2009)

Kayem 2008 (16) 32 years; P2 25 weeks 34 weeks/ Alive CS + Segmental

Weyerman 1989 (11) 38 years; P0 16 weeks 26 weeks/ Neonatal

Iloabachie 1993 (13) 26 years; P0 At delivery 37 weeks/twins

Gestat age at delivery/Outcome

death

alive

Treatment Blood transfusion

in Units

18 Units

5 Units

Not stated

CS + TAH 4 Units

8 Units

52 Units

7 Units

4 Units

5 Units

20 Units

resection of the uterine wall and placenta; No Transfusions

CS 16 Units

No transfusions

Maternal age Parity

deliveries.

Author, Year Reference

effacement and dilatation and a bulging lower uterine segment. These findings are indicative of two impending perinatal complications of CIP: preterm premature rupture of amniotic membranes and preterm birth. Eight of thirteen CIP (61.5%) delivered prematurely. The gestational age range at delivery was 26 to 34 weeks (4, 6, 8-11, 15, 16). Seven out of eight prematurely born babies survived (87.5%). One neonatal death occurred following delivery at 26 weeks of gestation (11).

The diagnosis of CIP is confirmed by medical imaging and intraoperative findings.

Sonography has made early diagnosis of CP and CIP possible and has replaced histologic diagnosis (7). Transvaginal ultrasound has been able to identify CIP at 6 and 7 weeks of gestation in four patients with CIP which reached neonatal viability (4, 6, 7, 12), whereas abdominal ultrasound diagnosed three CIP in mid-trimester (9, 11, 16). Two ultrasound criteria have been proposed to support a diagnosis of CIP and differentiate it from CP: a well-preserved and closed cervical canal, thus ruling out CP and more than half of the uterine cavity above the gestational sac uninvolved by gestational sac implantation (4, 6) Image 3.1. Magnetic Resonance Imaging was useful in distinguishing between CP and CIP (17, 18) Image 3.2.

Intra-operatively the diagnosis of CIP is confirmed by the following findings: a small sized, empty uterine corpus and fundus, an abnormally distended and thin walled lower uterine segment, a placenta implanted below the peritoneal reflection of the anterior and posterior surfaces of the uterus, a densely adherent placenta, placental penetration and neovascularization visible under the serosal surface (6, 7, 12).

Image 3.1. Ultrasound of Cervical pregnancy

Term Extra-Uterine Pregnancy 169

Once a CIP is diagnosed in the first trimester or early mid-trimester, termination of pregnancy should be offered after patient counseling. The latter should emphasize the possibility of severe life-threatening maternal and neonatal morbidity associated with continuation of the pregnancy (preterm delivery, postpartum hemorrhage, and hysterectomy) as opposed to the high success rate of early pregnancy termination by conservative, fertility sparing management (1, 6, 7, 17). If continuing the CIP is the patient's request after informed consent, then careful antenatal and perinatal management planning is imperative. Consideration should be given to timely transfer to a referral center with adequate resources: medical imaging and interventional radiology, extensive blood bank capabilities, adult and neonatal intensive care unit and surgical expertise to control massive postpartum hemorrhage. Continuous maternal hospitalization is advised in women with repeated antepartum bleeding or reduced cervical length (6). Transvaginal cervical length assessments should complement serial fetal ultrasound surveillance and alert the clinician about the possibility of preterm delivery (4, 6, 12). Delivery planning should ensure the availability of a large supply of blood and blood products. Eleven of thirteen women (84.6%) with advanced CIP received intra and/or postpartum blood transfusions (4, 6 - 15). Ten women were transfused 139 units of packed red blood cells, an average of 14 units per patient (4, 6 – 9, 11-15). These figures underscore the life-threatening nature of postpartum bleeding and the need of adequate blood bank services. Cesarean section is considered the safest route of delivery (6). Vaginal delivery remains an option and was accomplished in two women (8, 15). In the absence of a hemorrhagic emergency, placement of hypogastric artery catheters prior to delivery enables immediate internal iliac and uterine artery occlusion by embolization in the event of massive postpartum bleeding. (4).Eleven out of thirteen women with advanced CIP (84.6%) had a total abdominal hysterectomy after delivery of a viable newborn. The high postpartum hysterectomy rate has several reasons: the diagnosis is un-expectantly entertained at the time of delivery, the life-threatening nature of the postpartum hemorrhage and the lack of expertise in conservative operative techniques employed to control postpartum hemorrhage. Despite these challenges, the overall neonatal survival rate was 93%. Thirteen out of fourteen babies survived and one

The subsequent reproductive performance after CP was reassuring in 37 reported gestations: 54% of women had a term delivery, 14% had a premature delivery and 8% experienced a first trimester spontaneous abortion (19). Notwithstanding this argument, recurrent, consecutive CP were reported after use of assisted reproductive technology (20, 21). The subsequent successful obstetric experience after CP, reaffirms the enthusiasm for conservative, fertility sparing treatment enabled by early diagnosis. The reproductive performance after CIP remains elusive as the obstetric experience is limited to a single gestation that occurred in one of the two women whose uterus was preserved after term

Term tubal pregnancy, however is extremely rare. Review of the literature revealed that at least over 13 cases of term tubal pregnancy have been reported. Most of them were published in the nineteen fifties. The most recent article on this subject was published in 2010. So, despite being a rather rare event, it can still be encountered especially in places

CIP was a twin gestation delivered at term (13).

delivery of a CIP (16).

**4.1 Introduction** 

**4. Term tubal pregnancy** 

with limited medical facilities.

Image 3.2. MRI of Cervical pregnancy

#### **3.3 Treatment**

There are no clinical guidelines for the management of CIP as no center has accumulated enough data and experience with the treatment of this rare entity. Individual case reports, despite their inherent shortcomings, serve as reference in formulating management strategies for CIP which attained neonatal viability.

The management of CIP is dictated by the timing of the diagnosis.

If the diagnosis of CIP is made un-expectantly at the time of delivery, as it occurred in 38.5% of the reported advanced CIP, the therapeutic priority is to minimize the risks of catastrophic postpartum hemorrhage. This can be achieved by controlling the bleeding and replacement of the blood loss. Surgical occlusion of the internal iliac and uterine arteries or segmental resection of the uterine wall and attached placenta (16) could be initially employed if continuing fertility is desired and surgical expertise is available. Of the five women diagnosed at the time of delivery four required a total abdominal hysterectomy (3, 8, 10, 15) for control of postpartum hemorrhage, including the two women who were delivered vaginally (8, 15). This underscores the difficulty in controlling massive postpartum hemorrhage in previously unsuspected advanced CIP.

There are no clinical guidelines for the management of CIP as no center has accumulated enough data and experience with the treatment of this rare entity. Individual case reports, despite their inherent shortcomings, serve as reference in formulating management

If the diagnosis of CIP is made un-expectantly at the time of delivery, as it occurred in 38.5% of the reported advanced CIP, the therapeutic priority is to minimize the risks of catastrophic postpartum hemorrhage. This can be achieved by controlling the bleeding and replacement of the blood loss. Surgical occlusion of the internal iliac and uterine arteries or segmental resection of the uterine wall and attached placenta (16) could be initially employed if continuing fertility is desired and surgical expertise is available. Of the five women diagnosed at the time of delivery four required a total abdominal hysterectomy (3, 8, 10, 15) for control of postpartum hemorrhage, including the two women who were delivered vaginally (8, 15). This underscores the difficulty in controlling massive

Image 3.2. MRI of Cervical pregnancy

strategies for CIP which attained neonatal viability.

The management of CIP is dictated by the timing of the diagnosis.

postpartum hemorrhage in previously unsuspected advanced CIP.

**3.3 Treatment** 

Once a CIP is diagnosed in the first trimester or early mid-trimester, termination of pregnancy should be offered after patient counseling. The latter should emphasize the possibility of severe life-threatening maternal and neonatal morbidity associated with continuation of the pregnancy (preterm delivery, postpartum hemorrhage, and hysterectomy) as opposed to the high success rate of early pregnancy termination by conservative, fertility sparing management (1, 6, 7, 17). If continuing the CIP is the patient's request after informed consent, then careful antenatal and perinatal management planning is imperative. Consideration should be given to timely transfer to a referral center with adequate resources: medical imaging and interventional radiology, extensive blood bank capabilities, adult and neonatal intensive care unit and surgical expertise to control massive postpartum hemorrhage. Continuous maternal hospitalization is advised in women with repeated antepartum bleeding or reduced cervical length (6). Transvaginal cervical length assessments should complement serial fetal ultrasound surveillance and alert the clinician about the possibility of preterm delivery (4, 6, 12). Delivery planning should ensure the availability of a large supply of blood and blood products. Eleven of thirteen women (84.6%) with advanced CIP received intra and/or postpartum blood transfusions (4, 6 - 15). Ten women were transfused 139 units of packed red blood cells, an average of 14 units per patient (4, 6 – 9, 11-15). These figures underscore the life-threatening nature of postpartum bleeding and the need of adequate blood bank services. Cesarean section is considered the safest route of delivery (6). Vaginal delivery remains an option and was accomplished in two women (8, 15). In the absence of a hemorrhagic emergency, placement of hypogastric artery catheters prior to delivery enables immediate internal iliac and uterine artery occlusion by embolization in the event of massive postpartum bleeding. (4).Eleven out of thirteen women with advanced CIP (84.6%) had a total abdominal hysterectomy after delivery of a viable newborn. The high postpartum hysterectomy rate has several reasons: the diagnosis is un-expectantly entertained at the time of delivery, the life-threatening nature of the postpartum hemorrhage and the lack of expertise in conservative operative techniques employed to control postpartum hemorrhage. Despite these challenges, the overall neonatal survival rate was 93%. Thirteen out of fourteen babies survived and one CIP was a twin gestation delivered at term (13).

The subsequent reproductive performance after CP was reassuring in 37 reported gestations: 54% of women had a term delivery, 14% had a premature delivery and 8% experienced a first trimester spontaneous abortion (19). Notwithstanding this argument, recurrent, consecutive CP were reported after use of assisted reproductive technology (20, 21). The subsequent successful obstetric experience after CP, reaffirms the enthusiasm for conservative, fertility sparing treatment enabled by early diagnosis. The reproductive performance after CIP remains elusive as the obstetric experience is limited to a single gestation that occurred in one of the two women whose uterus was preserved after term delivery of a CIP (16).

#### **4. Term tubal pregnancy**

#### **4.1 Introduction**

Term tubal pregnancy, however is extremely rare. Review of the literature revealed that at least over 13 cases of term tubal pregnancy have been reported. Most of them were published in the nineteen fifties. The most recent article on this subject was published in 2010. So, despite being a rather rare event, it can still be encountered especially in places with limited medical facilities.

Term Extra-Uterine Pregnancy 171

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[3] Bouyer J, Coste J, Fernandez H et al. Sites of ectopic pregnancies: a 10 year population-

[4] Bertrand G, Le Ray C, Simard-Emond L, et al. Imaging in the management of abdominal

[5] Zeck W, Kelters I, Winter R, et al. Lessons learned from four advanced abdominal pregnancies at an East African Health Center. J Perinat Med 2007; 35: 278-281. [6] Gerli S, Rosetti D, Baiocchi G, et al. Early ultrasonographic diagnosis and laparoscopic

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Fig. 4.2. Reatained term tubal pregnancy

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2009;31(1): 57-62.

**5. References** 

521.

192-194.

103-105.

61.
