Overview
Termination of Pregnancy
1. Clinical Overview
Summary
Termination of Pregnancy (TOP) refers to the intentional ending of a pregnancy before viability, by medical or surgical means. In the UK, it is legal under the Abortion Act 1967 (as amended by the Human Fertilisation and Embryology Act 1990), which permits termination up to 24 weeks under specific grounds, and beyond 24 weeks in exceptional circumstances (e.g., severe fetal abnormality, risk to the mother's life). Methods include:
- Medical: Mifepristone followed by Misoprostol (Can be used at any gestation).
- Surgical: Vacuum Aspiration (less than 14 weeks) or Dilatation & Evacuation (D&E, >14 weeks). Approximately 200,000 abortions are performed annually in England and Wales. [1,2]
Clinical Pearls
Ground C is Most Common (>98%): "The pregnancy has not exceeded its 24th week and that the continuance of the pregnancy would involve risk, greater than if the pregnancy were terminated, of injury to the physical or mental health of the pregnant woman..."
Two Doctors' Signatures: Legally, two registered medical practitioners must sign the HSA1 form (though in some telemedicine contexts, this has been modified).
Exclude Ectopic FIRST: Before any TOP, confirm intrauterine pregnancy with ultrasound (or hCG levels if very early). Treating an undiagnosed ectopic with medical TOP is dangerous.
Anti-D for Surgical TOP (and Medical >10 weeks): Rhesus-negative women require Anti-D prophylaxis to prevent sensitisation if surgical, or if medical TOP after 10 weeks.
2. Epidemiology
Demographics (UK)
- Incidence: ~200,000 abortions per year in England & Wales (2022 data).
- Rate: Approximately 18 per 1,000 women aged 15-44.
- Gestation: Majority (80%+) performed before 10 weeks. Very few after 20 weeks.
- Method: Medical TOP now accounts for >85% of all abortions.
- Age: Highest rates in women aged 20-24.
Grounds (UK Law)
| Ground | Description | Time Limit |
|---|---|---|
| A | Risk to life of pregnant woman | No limit |
| B | To prevent grave permanent injury to physical/mental health | No limit |
| C | Risk of injury to physical/mental health of woman (MOST COMMON >98%) | 24 weeks |
| D | Risk of injury to physical/mental health of existing children | 24 weeks |
| E | Substantial risk of serious fetal handicap | No limit |
3. Pathophysiology
Medical TOP Mechanism
- Mifepristone (Progesterone Receptor Antagonist):
- Blocks progesterone action at the endometrium.
- Causes decidual necrosis and detachment of the pregnancy from the uterine wall.
- Softens and dilates the cervix.
- Misoprostol (Prostaglandin E1 Analogue):
- Given 24-48 hours after Mifepristone.
- Causes uterine contractions.
- Promotes cervical ripening.
- Expels the products of conception.
Surgical TOP Mechanism
- Cervical Dilation: Mechanical or with prostaglandins (Misoprostol or Osmotic dilators like Dilapan).
- Vacuum Aspiration (Manual or Electric): A cannula is inserted through the cervix, and suction removes the products of conception. Typically less than 14 weeks.
- Dilatation & Evacuation (D&E): For later gestations (>14 weeks). Cervical dilation followed by instrumental evacuation of the uterus.
4. Differential Diagnosis (Pregnancy Complications)
| Condition | Key Features |
|---|---|
| Ectopic Pregnancy | MUST EXCLUDE. Abdominal pain, vaginal bleeding, positive hCG but no IUP on scan. Adnexal mass. |
| Miscarriage (Spontaneous) | Bleeding/cramping with pregnancy loss. Managed expectantly, medically, or surgically. |
| Gestational Trophoblastic Disease (GTD) | "Snowstorm" appearance on US. Very high hCG. No fetus. |
| Cervical Ectropion | Bleeding on contact. Benign. Not pregnancy loss. |
5. Clinical Presentation
Pre-Procedure Consultation
Legal Requirements (UK)
Confirm Pregnancy
Urinary hCG or serum.
Gestation Dating
LMP and/or Ultrasound Scan.
Location
Confirm Intrauterine pregnancy (Rule out Ectopic).
Blood Group
Check Rhesus status for Anti-D consideration.
STI Screening
Offer Chlamydia and Gonorrhoea testing. Treat or provide prophylactic antibiotics.
Counselling
Non-directive. Explore options (Continue pregnancy, Adoption, Termination). Ensure decision is voluntary.
Consent
Informed consent for procedure and potential complications.
6. Investigations
Standard Pre-Procedure
- Urinary hCG: Confirm pregnancy.
- Ultrasound Scan (Transvaginal preferred for early pregnancy):
- Confirm viability.
- Confirm location (Intrauterine vs Ectopic).
- Determine gestation.
- Blood Group & Rhesus Status: Essential for Anti-D planning.
- Haemoglobin: If anaemia suspected or heavy bleeding anticipated.
- STI Screen: Chlamydia (Vulvo-vaginal swab/urine NAAT), Gonorrhoea.
Optional
- Clotting Screen: If bleeding disorder suspected.
7. Management
Management Algorithm
TERMINATION OF PREGNANCY
(Confirmed Intrauterine Pregnancy)
↓
COUNSELLING & CONSENT
(HSA1 Form - 2 Signatures)
↓
CHOOSE METHOD
(Patient Choice + Gestation)
┌──────────────┴──────────────┐
MEDICAL SURGICAL
(Any Gestation) (less than 14 weeks: MVA)
(>14 weeks: D&E)
↓ ↓
MIFEPRISTONE 200mg PO CERVICAL PREPARATION
(Anti-Progesterone) (Misoprostol or
Osmotic Dilator)
↓ (24-48h later) ↓
MISOPROSTOL 800mcg PROCEDURE
(PV/SL/Buccal) (Under LA/Sedation/GA)
↓ ↓
EXPULSION OF VACUUM ASPIRATION
PRODUCTS OR D&E
(Pass at home or clinic) ↓
↓ ANTI-D IF RH NEG
ANTI-D IF RH NEG ↓
(If >10 weeks gestation) FOLLOW-UP
↓
FOLLOW-UP
(Low threshold for review
if incomplete/infection)
Method Selection
| Factor | Medical | Surgical |
|---|---|---|
| Gestation | Any (especially early less than 10w, or 2nd trimester) | Typically less than 14w (MVA) or >14w (D&E) |
| Setting | Home or Clinic | Day case, Hospital/Clinic |
| Anaesthesia | None | Local / Sedation / GA |
| Time to Completion | Days (Bleeding over hours-days) | Immediate (procedure completes same day) |
| Patient Preference | More "natural", Private (at home) | Quick, Definitive |
Medical TOP Protocol
- Mifepristone 200mg oral (Day 1).
- Misoprostol 800mcg (Day 2-3, i.e., 24-48h later):
- Routes: Vaginal (most effective), Buccal, Sublingual.
- May be done at home for early gestations (less than 10 weeks).
- Expulsion: Patient passes products at home or clinic. Bleeding and cramping expected.
- Follow-Up: Advise signs of failed/incomplete (Persistent heavy bleeding, Fever, Persistent pregnancy symptoms). LSCS is performed if incomplete.
Surgical TOP Protocol
- Cervical Preparation:
- Misoprostol (400mcg PV 2-3h before) OR Osmotic dilators (e.g., Dilapan S overnight) for late 1st trimester / 2nd trimester.
- Procedure:
- Manual Vacuum Aspiration (MVA) or Electric Vacuum Aspiration (EVA).
- D&E for >14 weeks.
- Anaesthesia: Local (with sedation) or General Anaesthesia.
- Post-Procedure: Observation, then discharge.
Anti-D Prophylaxis
- Rhesus-Negative Women:
- Surgical TOP: Always give Anti-D (500 IU IM).
- Medical TOP: Give Anti-D if gestation >10 weeks.
- (At less than 10 weeks medical, sensitisation risk is very low; current NICE guidance does not mandate Anti-D for early medical TOP).
Antibiotic Prophylaxis
- Reduces risk of post-procedural infection.
- Common regimen: Metronidazole + Doxycycline (or treat known Chlamydia).
Contraception
- Discuss and offer contraception at time of procedure.
- LARC (Coil, Implant) can be inserted immediately post-surgical TOP or after confirmed completion of medical TOP.
- Fertility returns rapidly (Ovulation can occur within 2 weeks).
8. Complications
Immediate
- Haemorrhage: Rare. May require uterotonics, surgical evacuation, or transfusion.
- Failed/Incomplete Abortion: Retained products. May need further medical or surgical management.
- Uterine Perforation (Surgical): Rare (less than 1%). May require laparoscopy/laparotomy if bowel/vessel injury.
Early (Days)
- Infection (Endometritis/Sepsis): Fever, Offensive discharge, Abdominal pain. Requires antibiotics (broad-spectrum). Rare but serious.
- Continuing Pregnancy (Especially Medical TOP): Pregnancy continues. Requires repeat procedure.
Late
- Cervical Incompetence (Rare, with repeated D&E).
- Uterine Scarring (Asherman's Syndrome): Very rare.
- Psychological Sequelae: Most women do not experience significant negative psychological effects. A minority may experience regret, grief, or depression.
Long-Term Fertility
- Properly performed TOP does NOT significantly affect future fertility or pregnancy outcomes.
9. Prognosis and Outcomes
- Success Rate: Medical TOP >95% complete expulsion at early gestations. Surgical TOP >99% complete.
- Safety: Legal TOP is extremely safe, with lower mortality than continuing pregnancy to term.
- Mortality: less than 1 per 100,000 procedures (significantly lower than maternal mortality from childbirth).
10. Evidence and Guidelines
Key Guidelines
| Guideline | Organisation | Key Recommendations |
|---|---|---|
| Abortion Care | NICE NG140 (2019) | Medical preferred less than 10w. Telemedicine OK. Home use of both drugs permitted. Anti-D guidance. |
| Best Practice in Abortion | RCOG (2022) | Comprehensive guidance. Antibiotic prophylaxis. Contraception provision. |
Legal Framework (UK)
- Abortion Act 1967 (+ HFE Act 1990 amendments): Sets legal grounds for TOP.
- HSA1 Form: Completed by two doctors.
- HSA4 Form: Notification to CMO.
11. Patient and Layperson Explanation
What is a Termination of Pregnancy?
It is an operation or a course of medication to end a pregnancy. It is legal in the UK when certain conditions are met and is a safe, common procedure.
What are my options?
- Continue the Pregnancy: You may choose to continue and raise the child or explore adoption.
- Medical Termination: You take tablets. The first tablet (Mifepristone) stops the pregnancy growing. The second tablets (Misoprostol), taken 24-48 hours later, cause the womb to contract and pass the pregnancy, similar to a miscarriage.
- Surgical Termination: A short procedure, usually under sedation or general anaesthetic, where the pregnancy is gently removed from the womb using suction.
Is it safe?
Yes. Legal abortion carried out in appropriate settings is very safe. Serious complications are rare.
Will it affect my future fertility?
No. A properly performed termination does not affect your ability to have children in the future.
Can I have contraception?
Yes, we strongly encourage discussing contraception. A coil or implant can even be fitted at the time of your procedure if you wish.
12. References
Primary Sources
- NICE. Abortion care (NG140). 2019.
- RCOG. Best Practice in Comprehensive Abortion Care. 2022.
- UK Department of Health. Abortion Statistics, England and Wales. 2023.
13. Examination Focus
Common Exam Questions
- Legal: "Most common ground for TOP in UK?"
- Answer: Ground C (Risk to physical/mental health of woman, less than 24 weeks). >98% of cases.
- Pharmacology: "Mechanism of Mifepristone?"
- Answer: Progesterone Receptor Antagonist. Causes decidual necrosis, detachment of pregnancy.
- Prophylaxis: "When is Anti-D given?"
- Answer: All Surgical TOP (Rh-Neg). Medical TOP if >10 weeks gestation (Rh-Neg).
- Complication: "Most serious early complication?"
- Answer: Sepsis (Post-abortal infection). Rare but life-threatening.
Viva Points
- HSA1 Form: Two doctors' signatures certifying legal grounds.
- Telemedicine: Explain how early medical TOP can now be managed remotely (NICE NG140).
Medical Disclaimer: MedVellum content is for educational purposes and clinical reference. Clinical decisions should account for individual patient circumstances. Always consult appropriate specialists.