A cervical ectopic pregnancy is a rare and dangerous condition where a fertilised egg attaches and starts to grow in the cervix (the lower part of the uterus that connects to the vagina) instead of in the main part of the uterus where it should normally develop. This type of pregnancy might not result in a live birth and can be very risky for the mother, potentially causing severe bleeding, hence it ends after the third trimester itself. However, if the fertilised egg implants are closer to the uterine cavity, known as a cervical-isthmic pregnancy, it may progress for a longer period.

Causes/Risk Factors for cervical ectopic pregnancy

The main risk factors for cervical ectopic pregnancy include:

Prior dilatation and curettage (D&C) procedures significantly increase the risk compared to intrauterine and tubal ectopic pregnancies. One study found the risk of CEP was 6 times higher with a prior D&C compared to tubal ectopic pregnancy.
Previous cervical excisional procedures like LEEP or conisation, also have a high effect size in predicting CEP compared to intrauterine and tubal ectopic pregnancies.
History of elective abortions, which is more common in CEP patients compared to those with intrauterine pregnancies.
Asherman's syndrome has been associated with CEP in some case reports.

Symptoms of Cervical Ectopic Pregnancy

The main symptoms signalling Cervical ectopic pregnancy include:

The most common symptom is painless vaginal bleeding, which can be profuse and is often the presenting complaint. The bleeding may be spotted, prolonged, or intermittent.
Some women may also present with gastrointestinal symptoms like nausea and vomiting, which can lead to an initial misdiagnosis of gastroenteritis rather than ectopic pregnancy.
Amenorrhea (absence of menstrual period) is a common symptom, but in some cases, abnormal bleeding may be mistaken for a normal menstrual period.
The cervix may appear soft, disproportionately large or barrel-shaped on physical examination.
The symptoms of cervical ectopic pregnancy can be like other types of ectopic pregnancy, making early diagnosis challenging.

Diagnosis of Cervical Ectopic Pregnancy

Cervical ectopic pregnancy is a rare and potentially life-threatening form of ectopic pregnancy where the embryo implants in the cervical canal. The diagnosis involves several steps:

Clinical Evaluation: Patients often present with painless vaginal bleeding during the first trimester. In some cases, abdominal pain and discomfort might be reported. A pelvic exam may reveal an enlarged and softer cervix, sometimes called the "hourglass uterus" sign.
Transvaginal Ultrasound: The most definitive diagnostic tool is transvaginal ultrasound, which typically shows an empty uterine cavity with a gestational sac, or fetal parts located in the cervical canal. The absence of a gestational sac in the uterine cavity further supports the diagnosis of cervical pregnancy.
Doppler Ultrasound: Doppler ultrasound may be used to assess blood flow around the gestational sac, which helps distinguish cervical pregnancy from other conditions like a miscarriage in progress.
Laboratory Tests: Elevated levels of hCG consistent with pregnancy are detected. However, the levels may not rise as expected in a normal intrauterine pregnancy.
Magnetic Resonance Imaging (MRI): MRI can be used in complex cases or when ultrasound findings are inconclusive, providing more detailed imaging to confirm the diagnosis and evaluate the extent of the cervical ectopic pregnancy.

Early and accurate diagnosis is critical for appropriate management and to minimize severe complications like heavy bleeding.

Management of Cervical Ectopic Pregnancy

Managing cervical ectopic pregnancy is complex due to the risk of severe bleeding and the potential for preserving future fertility. The approach to management depends on factors such as the gestational age, size and location of the pregnancy, and the patient's overall health. Here are the main strategies:

Medical Management: This chemotherapeutic agent is often the first-line treatment. It can be administered systemically or injected directly into the gestational sac under ultrasound guidance. Methotrexate works by inhibiting cell division, leading to the resolution of ectopic pregnancy. Alternatives or adjuncts to methotrexate, such as potassium chloride or hyperosmolar glucose, may be used to reduce vascularity and promote resorption of the pregnancy.
Surgical Management:
- Dilation and Curettage (D&C): This procedure involves the surgical removal of the contents of the cervix. It is usually performed under ultrasound guidance to minimize complications.
- Suction Curettage: Like D&C but uses suction to evacuate the contents, which can be less traumatic and may reduce the risk of bleeding.
- Cervical Cerclage: This procedure involves placing a stitch around the cervix to control bleeding.
- Hysteroscopic Resection: Involves the use of a hysteroscope to visualize and remove ectopic pregnancy.
- Transvaginal Ultrasound-Guided Aspiration: A minimally invasive technique that can be used to aspirate the gestational sac under ultrasound guidance.
Adjunctive Measures: This procedure involves blocking the blood flow to the uterus to control bleeding. It is typically used as an adjunct to other treatments. Vasopressin can be injected around the cervix to constrict blood vessels and reduce bleeding.
Expectant Management: In very early cases or when the pregnancy is resolved spontaneously, close monitoring with serial hCG levels and ultrasound may be considered.
Supportive Care: This may be necessary if significant bleeding occurs. Adequate pain control is important for patient comfort.
Follow-Up: Regular monitoring of hCG levels to ensure they are decreasing appropriately. Follow-up ultrasounds to confirm the resolution of the ectopic pregnancy.

Each case of cervical ectopic pregnancy is unique, and the management plan should be individualised based on the patient's clinical condition and preferences. Early diagnosis and appropriate intervention are crucial to minimising complications and preserving fertility when possible.

Complications presented by Cervical Ectopic Pregnancy

Cervical Ectopic Pregnancy can present the following complications:

Severe Bleeding: The most immediate and life-threatening complication is massive haemorrhage. The cervix has a rich blood supply but can't contract like the uterus to stop bleeding. This can lead to:

1. Shock

Need for emergency blood transfusions
In extreme cases, it can be fatal if not treated promptly

2. Fertility Issues:

Damage to the cervix from the pregnancy or treatment can affect future fertility
Scarring might make it harder to conceive or carry future pregnancies to term

3. Psychological Impact:

The loss of the pregnancy and the traumatic experience can lead to depression, anxiety, or post-traumatic stress disorder
Cervical Damage: The growing pregnancy can weaken the cervix, potentially affecting its function in future pregnancies
This might increase the risk of preterm labour in subsequent pregnancies

4. Complications from Treatment:

Medication (like methotrexate) can cause side effects such as nausea, mouth sores, or rarely, liver problems
Surgical treatments carry risks like infection, further damage to the cervix or uterus, and risks associated with anaesthesia

5. Emergency Hysterectomy:

In severe cases, especially if there's uncontrollable bleeding, removal of the uterus might be necessary
This results in permanent infertility and can have a significant emotional impact.

6. Placenta Accreta: In rare cases where the pregnancy progresses, the placenta can grow too deeply into the cervical tissue, making removal dangerous

7. Infection: The cervix's location makes it more prone to ascending infections, which can lead to pelvic inflammatory disease

8. Long-term Cervical Issues:

Cervical incompetence in future pregnancies
Increased risk of cervical cancer (though this link is not firmly established and needs more research)

9. Recurrence: Having one cervical ectopic pregnancy slightly increases the risk of having another ectopic pregnancy in the future

10. Trophoblastic Disease: In very rare cases, the pregnancy tissue can develop into a form of cancer called gestational trophoblastic disease

Conclusion

Cervical ectopic pregnancy, a rare and potentially life-threatening condition, requires prompt and accurate diagnosis through clinical evaluation, transvaginal ultrasound, and laboratory tests. Effective management includes medical treatments like methotrexate, various surgical interventions, and adjunctive measures such as uterine artery embolization. Individualised care is crucial, considering the patient's condition and reproductive goals. Early detection and appropriate treatment are essential to mitigate complications, ensure patient safety, and preserve future fertility when possible.

Reference links:

https://exxcellence.org/list-of-pearls/diagnosis-and-management-of-cervical-ectopic-pregnancy/
https://en.wikipedia.org/wiki/Cervical_pregnancy
https://pubmed.ncbi.nlm.nih.gov/31811970/
https://gynecolsurg.springeropen.com/articles/10.1007/s10397-006-0224-y
https://www.cureus.com/articles/74475-cervical-ectopic-pregnancy-a-multidisciplinary-approach
https://www.mdpi.com/1648-9144/56/6/293