Role of Ultrasound Imaging and Management option for Caesarean scar Ectopic Pregnancy

Shah . Fatima, Vaithilingam . NQueen Alexandra Hospital, Southwick Hill Road. Cosham Portsmouth PO6 3LY, England

Background Case Histories & Management Conclusions

Discussion

•Implantation of pregnancy within a scar is a rare occurrence with only 50 reported cases

•Due to its rarity optimal management is yet to be established

•Imaging plays an important role as a diagnostic modality in skilled hands

•Increase in incidence is anticipated as number of caesarean delivery is increasing

•Implantation of a pregnancy within scar is a life threatening condition

•It should be part of differential diagnosis

•Women who had a scar pregnancy and are planning future pregnancy should be counselled to have early scan to confirm location

Introduction

Caesarean scar ectopic pregnancy is a rare condition which poses challenges for optimal management. Even though different modalities are available for the treatment early diagnosis improves the outcome and future fertility.

Background

It has an estimated incidence of 1: 1800 - 2200 pregnancies. The etiology of caesarean scar pregnancy is unclear. Previous cesarean section, myomectomy, adenomyosis, IVF, previous dilation and curettage, and manual removal of the placenta have been linked as risk factors. The overall incidence is however thought to be increasing as result of increasing caesarean section rate and assessment of early pregnancy complication using transvaginal scan.

Diagnosis

All four cases the diagnosis of scar pregnancy was made from transvaginal scan. All the cases demonstrate empty endometrial canal, empty endocervical canal, gestational sac developed in anterior part of lower uterine segment and very thin myometrium in between the bladder and gestational sac.

In addition we used Doppler study. Gestational sac above the uterine artery entry differentiated the scar ectopic from cervical pregnancy where the gestational sac is below the uterine artery.

Management

Methotrexate was used in all cases to suppress the trophoblastic activity. All patients responded to single dose methotrexate. Case 1 had evacuation following the methotrexate and KCl. Cervical cerclage was used to minimize blood loss. Careful counselling and patient compliance are important to achieve a successful clinical outcome with medical treatment

Follow up

Monitoring next pregnancy in early stage is important to exclude recurrent scar pregnancy1 patient had successful normal intrauterine pregnancy and uncomplicated C-section.

Methods

Ultrasound Imaging Criteria An empty uterine cavity & empty cervical canalDevelopment of the gestational sac in the anterior part of the uterine isthmusAn absence of healthy myometrium between the bladder and sacSac should be above the uterine artery

Transvaginal ultrasound image of scar ectopic

Sagittal section of uterus showing c-section scar pregnancy

Transverse section of uterus showing c-section scar

Retrospective analysis of Caesarean scar pregnancy and its outcome during the period of three years.

OPTIONALLOGO HERE

Empty endometrial cavity

Gestational Sac with Yolk sac

Empty Cervical Canal

Gestational sac growing towards bladder

Cases History Symptoms Diagnosis Outcomes

Case 1

34 yrTwo previous section

AsymptomaticBHCG 43681 IU

10 weeks POAUS: Confirmed single viable pregnancy of 9wks and I day, Situated very low in the uterine wall possibly located in previous LSCS scar

KCl and MethorexateEvacuation with cervical cerclage Two units blood transfusion

Had successful pregnancy in 2010Delivered by C - section & recovery uneventful

Case 2

39yrs oldTwo previous sectionsalpingectomy for tubal ectopic pregnancy in the past

Left iliac fossa painRight t shoulder tip pain and Six weeks amenorrheaBHCG 8431

US: 11x4x8 mm gestational sac with yolk sac at previous scarTrace amount free fluid

Treated with methotrexateD4 – BHCG 8431D35 – BHCG 14

Case3

Case 2 Presented after one year with seven weeks amenorrhea to exclude ectopic pregnancy

AsymptomaticBHCG 20543

US: Gestational sac in the scar live embryo at 6weeks 6 days

Fetocide with KCl followed with methotrexateD4 – BHCG 20543D40 – BHCG 10

Case 4

42 yrs oldTwo previous sectionEight week amenorrhea

Vaginal spottingLower abdominal painPatient declined to undergo any treatment readmitted 9 days later with severe lower abdominal pain

US: Gestational sac at scar with live embryo at 6weeks 3daysRepeat scan showed no cardiac pulsation

Agreed for methotrexate on second admissionHad two units blood transfusionD4 – BHCG 27706D17 – BHCG 1820BHCG monitoring was not possible due non compliance