Cervical ectopic pregnancy
Cervical ectopic pregnancy is a rare subtype of ectopic pregnancy.
It accounts for ~0.15-1% of all ectopic pregnancies.
Implantation of the fertilized ovum occurs within the cervix rather than the uterine cavity. Unless the fetal heart rate can be identified, it is difficult to distinguish from a miscarriage with fetal parts in the cervical os.
Can be seen as a gestational sac within the cervix which gives an hour-glass appearance to the uterus. Usually, internal os is closed. At times the gestational sac extends into the lower uterine segment (abnormally low sac position). There is hyperechoic decidual reaction around the gestational sac.
Colour Doppler imaging can be helpful in showing a hypervascular trophoblastic ring in the cervical region in cases of live cervical ectopic pregnancies.
Treatment and prognosis
The goal is to treat the condition whilst minimising the risk of severe haemorrhage, and to preserve the patient's future reproductive potential.
Medical management options include methotrexate (a folate antagonist) either administered systemically or by direct injection, or potassium chloride (direct injection).
Surgical curettage runs the risk of life threatening haemorrhage. A preoperative uterine embolisation is an option for reduction of haemorrhage risk 4,6,7.
Severe haemorrhage is the main complication of surgical management. It may result in the need for hysterectomy, and is potentially life threatening.
- it is important to consider miscarriage in progress as a differential when the gestational sac is located within the endocervical canal; features suggestive of a miscarriage include:
- absent embryonic cardiac activity
- open internal os: lack of typical hour glass appearance
- sac shape and location often changes on serial scans and it may be possible to alter the location of the sac with gentle probe maneuvering ("sliding sac sign")
- subsequent loss of the fetal sac on a repeat ultrasound confirms miscarriage
First trimester of pregnancy
- ultrasound findings in early pregnancy
- confirming intrauterine gestation
- pregnancy of unknown location (PUL)
first trimester vaginal bleeding
- ectopic pregnancy
failed early pregnancy
- pregnancy of uncertain viability (PUV)
- anembryonic pregnancy
- yolk sac abnormalities
- gestational trophoblastic disease
- subchorionic haemorrhage
- demise of a twin
- implantation bleeding
- aneuploidy testing
Ultrasound - obstetric
- ultrasound (introduction)
- obstetric ultrasound
first trimester and early pregnancy
- gestational sac
- yolk sac
- Beta-hCG levels
- ectopic pregnancy
- multiple gestations
- subchorionic hematoma
- failed early pregnancy
- fetal biometry
- fetal morphology assessment
- fetal echocardiography views
- nonvisualisation of the fetal stomach
- nuchal fold thickness
- absent nasal bone
- choroid plexus cysts
- enlarged cisterna magna
- shortened fetal long bones
- echogenic intracardiac focus (EIF)
- echogenic fetal bowel
- aberrant right sublavian artery
- fetal pyelectasis / fetal renal pelvic dilatation
- single umbilical artery
- sandal gap toes
- umbilical artery Doppler assessment
- fetal middle cerebral arterial Doppler assessment
- nuchal translucency
- chorionic villus sampling (CVS) and amniocentesis
- first trimester and early pregnancy
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