• Worldwide, approximately 73 million induced abortions occur annually (WHO, 2024 estimates) ^[1]
• Approximately 45% of all abortions globally are considered "unsafe" (performed by persons lacking necessary skills or in environments not conforming to minimal medical standards)
• Unsafe abortion remains a leading cause of maternal mortality, accounting for 4.7–13.2% of maternal deaths globally
• Rates are highest in regions with restrictive abortion laws — paradoxically, restricting access does not reduce abortion rates but shifts them to unsafe settings

• In Hong Kong, TOP is legally regulated under the Offences Against the Person Ordinance (Cap. 212) and the specific exemption provisions ^[2]
• The number of legal TOPs in Hong Kong has been declining over recent decades, reflecting improved contraceptive access and education
• In 2022, approximately 7,000–9,000 legal TOPs were performed in Hong Kong (Hospital Authority data)
• The majority are performed in the first trimester ( < 12 weeks)
• The most common indications in Hong Kong include: risk to physical/mental health of the woman, and fetal anomaly ^[2]

• Peak age group: 20–34 years
• Both nulliparous and multiparous women seek TOP
• In Hong Kong, a significant proportion are among married women (unlike some Western contexts where the majority are unmarried)

Under Hong Kong law (Offences Against the Person Ordinance, Cap. 212, Sections 46-47), abortion is a criminal offence UNLESS specific conditions are met ^[2]:

Legal grounds for TOP in Hong Kong ^[2]:

1. The pregnancy has NOT exceeded 24 weeks, AND
2. Two registered medical practitioners are of the opinion, formed in good faith, that:
   • Continuance of the pregnancy would involve risk to the life of the pregnant woman greater than if the pregnancy were terminated, OR
   • Continuance of the pregnancy would involve risk of injury to the physical or mental health of the pregnant woman greater than if the pregnancy were terminated, OR
   • There is substantial risk that if the child were born, it would suffer from such physical or mental abnormalities as to be seriously handicapped

OR, regardless of gestational age:

3. The termination is immediately necessary to save the life of the pregnant woman, OR
4. The termination is immediately necessary to prevent grave permanent injury to the physical or mental health of the pregnant woman

The procedure must be performed by a registered medical practitioner in an approved institution (i.e., a hospital) ^[2].

• The woman herself must give informed consent ^[2]
• For girls under 16 years, parental/guardian consent is required
• The partner's consent is NOT legally required (though counselling may involve the partner)
• Adequate counselling should be provided before and after the procedure, including discussion of alternatives (continuing pregnancy, adoption) ^[2]

• Uterus: A pear-shaped muscular organ, approximately 7–8 cm long in the non-pregnant state

  • Fundus: The dome-shaped portion above the tubal ostia
  • Body (corpus): The main part; contains the endometrium (where the embryo implants)
  • Isthmus: Narrow segment between body and cervix — becomes the lower uterine segment in pregnancy
  • Cervix: The cylindrical lower portion projecting into the vagina
    • Internal os: Upper opening of the cervical canal into the uterine cavity
    • Cervical canal: Contains mucus-secreting glands; the canal is ~2.5 cm long
    • External os: Lower opening into the vagina; nulliparous = circular, parous = slit-like

• Myometrium: Three layers of smooth muscle

  • Outer longitudinal
  • Middle interlacing (figure-of-eight pattern) — this is the "living ligature" layer that compresses blood vessels after placental delivery to achieve haemostasis
  • Inner circular

• Blood supply: Uterine arteries (branches of internal iliac) → arcuate arteries → radial arteries → spiral arteries (in the endometrium). The spiral arteries are remodelled during pregnancy by trophoblast invasion to create low-resistance, high-flow vessels for placental perfusion.

• Cervical anatomy for TOP: The cervix must be dilated for surgical TOP. The internal os is the narrowest point and the main barrier. Forced, rapid dilation risks cervical tears and cervical incompetence.

• First trimester (≤12 weeks):

  • Uterus remains within the pelvis
  • Cervix is firm, closed
  • Gestational sac and embryo/fetus are relatively small
  • Placentation is still maturing

• Second trimester (13–24 weeks):

  • Uterus is abdominal
  • Greater vascularity → increased bleeding risk
  • Fetus is larger → requires more cervical dilation for surgical evacuation or induction for medical
  • Placenta is well-established → higher risk of retained products and haemorrhage

1. Risk to maternal physical health

   • Severe cardiac disease (e.g., Eisenmenger syndrome, severe pulmonary hypertension — pregnancy carries > 30% mortality)
   • Severe renal disease
   • Malignancy requiring treatment incompatible with pregnancy (e.g., certain chemotherapy regimens, pelvic radiation)
   • Severe pre-existing medical conditions worsened by pregnancy

2. Risk to maternal mental health

   • Pre-existing or pregnancy-related psychiatric illness (severe depression, psychosis)
   • Social circumstances contributing to psychological distress
   • In practice in Hong Kong, this is the most commonly invoked ground — many women cite inability to cope, relationship breakdown, financial hardship, or unwanted pregnancy as causing significant mental distress

3. Immediately necessary to save life / prevent grave injury

   • Ruptured ectopic pregnancy (though this is usually managed as a gynaecological emergency rather than "TOP" per se)
   • Severe pre-eclampsia / eclampsia at pre-viable gestation
   • Septic abortion with maternal compromise

1. Serious fetal anomaly (substantial risk of serious handicap)
   • Chromosomal abnormalities: Trisomy 13 (Patau), Trisomy 18 (Edwards), Trisomy 21 (Down syndrome — this is nuanced and involves extensive counselling)
   • Structural anomalies: anencephaly, severe spina bifida, severe cardiac malformations, bilateral renal agenesis (Potter sequence)
   • Genetic conditions: severe forms of thalassaemia (particularly relevant in Hong Kong where α- and β-thalassaemia carrier rates are high — approximately 8.5% of the HK population are carriers), severe metabolic disorders
   • Multiple anomalies incompatible with life

• Failed contraception (including failed emergency contraception)
• Unplanned/unwanted pregnancy
• Pregnancy resulting from sexual assault
• Molar pregnancy (hydatidiform mole — requires evacuation, which is technically a form of TOP)

These overlap with contraceptive failure / non-use:

1. Lack of access to effective contraception
2. Incorrect or inconsistent use of contraception
   • Oral contraceptive pills — efficacy reduced by missed pills, vomiting/diarrhoea, enzyme-inducing drugs ^[3]
3. Young age / adolescence — less consistent contraceptive use, less access, less knowledge
4. Low socioeconomic status
5. Relationship instability
6. Substance abuse — impaired judgment
7. Sexual assault
8. Failed sterilization (rare but occurs)

Understanding these guides pre-procedure assessment:

The entire process hinges on the hormonal maintenance of pregnancy:

After the pregnancy is removed (by either method), the placental bed is exposed — this is a raw, vascular surface where spiral arteries previously supplied the placenta. Haemostasis depends on:

1. Myometrial contraction — the "living ligature" effect where the interlacing muscle fibres compress the blood vessels
2. Coagulation cascade — forming clots at the vessel ends
3. Endometrial regeneration — eventually, the endometrium regrows to cover the raw surface

If the uterus fails to contract (atony) or products are retained (preventing full contraction), bleeding continues.

• The uterine wall becomes thinner as the uterus expands
• Greater vascularity → more severe haemorrhage if perforated
• More dilation required → more force → more risk
• If bowel is drawn into the uterus through a perforation during suction → catastrophic bowel injury

• Urine β-hCG (qualitative — confirms pregnancy)
• Transvaginal ultrasound (TVUS) — confirms:
  • Intrauterine location (excludes ectopic — ectopic pregnancy is a contraindication to uterine TOP)
  • Viability (fetal heartbeat)
  • Gestational age (crown-rump length in first trimester)
  • Number of fetuses
  • Excludes molar pregnancy

• By last menstrual period (LMP) and confirmed by ultrasound
• This determines which method is appropriate and whether it falls within the legal limit

• History: medical conditions, allergies, medications, previous surgery (especially uterine surgery)
• Blood tests:
  • FBC — baseline Hb (anaemia ↑ risk with any bleeding)
  • Blood group and Rh status — Anti-D immunoglobulin must be given to Rh-negative women to prevent Rh isoimmunisation ^[2]
  • Coagulation screen (if indicated)
  • STI screening (Chlamydia, Gonorrhoea) — infection increases risk of post-TOP endometritis

• Non-directive counselling — presenting all options (continuing pregnancy, adoption, TOP) without bias
• Discussion of methods available, risks, and complications
• Psychological support and follow-up arrangements
• Contraception counselling — ideally, effective contraception should be started immediately post-TOP to prevent repeat unintended pregnancy ^[3]

• Written informed consent
• Two doctors must certify the legal grounds for TOP (Form A equivalent in HK practice) ^[2]

These are NOT used for TOP (they are the opposite — used to STOP premature contractions), but understanding them helps you understand the pharmacology from first principles.

Included here for completeness as per the lecture ^[3]:

Ectopic pregnancy presents with the classic triad of missed period, vaginal bleeding, and abdominal pain ^[5]. However, clinical diagnosis can only be made in half of the patients ^[5] — meaning the other half present atypically.

Key atypical features ^[2][4]:

• Gastrointestinal symptoms may be prominent in ectopic pregnancy, notably diarrhoea and painful defecation — because blood in the pouch of Douglas irritates the rectum
• Syncope or shoulder pain ^[5] — shoulder tip pain is referred pain from diaphragmatic irritation by haemoperitoneum (C3-5 phrenic nerve dermatome)
• Abdominal tenderness with varying degree of peritonism; cervical excitation ^[5]

Risk factors for ectopic ^[5]:

• Previous ectopic pregnancy
• Tubal damage from infection/surgery
• History of infertility
• Assisted reproduction techniques
• Increased age
• Smoking

USS features suggestive of ectopic pregnancy ^[5]:

• "Bagel sign" — a hyperechoic ring (the gestational sac with trophoblast) in the adnexa
• Complex, inhomogeneous adnexal mass separate from the ovary
• Empty uterus or pseudo-sac (a pseudo-sac is fluid collecting in the endometrial cavity due to decidual reaction — it lacks the double decidual sign of a true gestational sac)
• Moderate to large amount of free fluid in POD suggestive of haemoperitoneum ^[5]

GTD is an important differential diagnosis of threatened miscarriage ^[5] and can also present as an apparently normal early pregnancy requesting TOP. It encompasses:

Why it matters for TOP DDx: If a molar pregnancy is managed as a standard medical TOP (mifepristone + misoprostol), there is risk of:

• Incomplete evacuation (molar tissue is bulky and may not pass completely)
• Missing the diagnosis → no β-hCG follow-up → GTN develops undetected
• The standard approach for molar pregnancy is suction evacuation (NOT medical) + histological examination of products + serial β-hCG monitoring

These conditions can mimic early pregnancy symptoms or coexist with pregnancy.

These are important because they can be misdiagnosed as a gynaecological emergency (and vice versa).

Ideally, all women should undergo ultrasound examination before termination of pregnancy to establish gestational age, viability, and site ^[2][4].

Why? Because if the pregnancy is not intrauterine, proceeding with uterine TOP is:

• Futile (you won't treat the actual pregnancy)
• Dangerous (ectopic persists and may rupture)
• Misleading (false reassurance that the pregnancy has been terminated)

How is IUP confirmed?

The Discriminatory Zone concept:

This is a critical concept linking serum β-hCG to expected USS findings.

• The discriminatory zone is the serum β-hCG level above which a gestational sac should be visible on TVUS if an IUP is present
• Traditionally quoted as 1,000–1,500 mIU/mL for TVUS (some centres use 2,000)
• If serum β-hCG is above the discriminatory zone and NO IUP is seen on TVUS → strongly suspect:
  • Ectopic pregnancy
  • Recent complete miscarriage
  • Very rarely, early multiple pregnancy or technical factors (obesity, fibroids, retroverted uterus)

Gestational age must be determined to confirm the pregnancy falls within the legal limit (≤ 24 weeks in Hong Kong) and to select the appropriate TOP method ^[2][4].

Methods of dating:

Why does gestational age matter so much?

• Determines legality (≤ 24 weeks for standard grounds in HK)
• Determines method: medical vs surgical, first-trimester vs second-trimester protocol
• Determines risk: later gestation = higher complication rates
• Determines cervical preparation: more needed at later gestations

Two registered medical practitioners must certify, in good faith, that one of the legal grounds is met ^[2][4]. This is a legal, not a diagnostic criterion per se, but it must be documented before proceeding. (Covered in detail in Part 1.)

This is the pre-procedural assessment — confirming the woman can safely undergo medical or surgical TOP. Detailed investigations are outlined below.

What it is: A qualitative immunoassay detecting the β-subunit of human chorionic gonadotropin (hCG) in urine.

Why the β-subunit? Because the α-subunit of hCG is shared with TSH, LH, and FSH ^[6]. Testing the β-subunit ensures specificity for hCG (i.e., pregnancy).

Why we do it:

• A negative pregnancy test effectively rules out ectopic pregnancy ^[5] — this simple bedside test is the most important initial investigation
• Confirms the basic premise (is there a pregnancy at all?)

Key findings and interpretation:

Sensitivity: Modern urine tests detect β-hCG ≥ 20–25 mIU/mL → positive from approximately the day of the expected period.

Pitfall: A very recently completed miscarriage may still show positive β-hCG (takes 1-2 weeks to clear). Also, extremely high β-hCG (e.g., molar pregnancy) can cause a false negative due to the "hook effect" — excess antigen saturates both the capture and detection antibodies, preventing sandwich formation. If clinical suspicion is high, always confirm with serum β-hCG.

What it is: A quantitative blood test measuring the exact level of β-hCG in mIU/mL.

Why we do it:

• Correlates with gestational age and expected USS findings (discriminatory zone)
• Serial measurements (48-hour trend) help distinguish viable IUP, ectopic, and failing pregnancy
• hCG assay is a key investigation for suspected ectopic pregnancy ^[5]

Key findings and interpretation:

Discriminatory zone (for TVUS):

• 1,000–2,000 mIU/mL: Above this, a gestational sac should be visible on TVUS if it is an IUP
• But remember the HKU study: viable IUP was found with β-hCG up to 9,083 mIU/mL where no IUP was initially seen — so do NOT make irreversible decisions based on a single β-hCG level in stable patients ^[5]

What it is: High-frequency ultrasound probe placed in the vagina, providing close proximity to the uterus and adnexa → superior resolution compared to transabdominal USS for early pregnancy assessment.

Why we do it: To establish gestational age, viability, and site of the pregnancy ^[2][4].

Signs of intrauterine pregnancy on TVUS ^[10]:

Features suggestive of ectopic pregnancy on TVUS ^[5]:

Features of molar pregnancy:

• "Snowstorm" or "cluster of grapes" appearance — multiple cystic spaces within the uterine cavity
• Uterus larger than expected for dates
• May have bilateral theca lutein cysts (from hCG hyperstimulation of the ovaries)
• No fetal parts in complete mole; some fetal parts in partial mole

Features of miscarriage:

Why: Hb level establishes baseline ^[5] — essential because:

• Existing anaemia increases risk from any bleeding
• Provides comparison if post-procedure haemorrhage occurs
• Also note MCV ^[5] — microcytosis may suggest pre-existing iron deficiency (chronic blood loss, dietary insufficiency, thalassaemia trait — especially relevant in Hong Kong)

Rh factor must be checked ^[5].

Why? Rh-negative women exposed to Rh-positive fetal red cells during TOP develop anti-D antibodies → these persist and cause haemolytic disease of the fetus and newborn (HDFN) in future Rh-positive pregnancies.

Rh-negative prevalence in Hong Kong: ~0.3-0.5% (much lower than Caucasian populations ~15%) — but when it does occur, the consequences of missed anti-D prophylaxis are devastating.

Why: In case haemorrhage occurs during or after the procedure, compatible blood must be available.

When indicated:

• History of bleeding disorder
• Anticoagulant use
• Liver disease
• Septic abortion (risk of DIC — septic abortion is a known cause of obstetric DIC ^[11])
• Second-trimester TOP (higher bleeding risk)

Not routine for straightforward first-trimester TOP in an otherwise healthy woman.

Why: Ascending infection from untreated cervical/vaginal STIs during instrumentation → endometritis → pelvic sepsis → tubal damage → future fertility consequences.

Two approaches:

1. "Screen and treat" — test all women; treat those who test positive (delays procedure)
2. "Prophylactic antibiotics for all" — give empiric antibiotics (e.g., azithromycin 1g PO or doxycycline 100mg BD x 7 days) to all women undergoing surgical TOP regardless of screening results

Most guidelines (including RCOG) recommend either universal screening or universal prophylactic antibiotics. In practice, many centres provide prophylactic antibiotics to all.

Not routinely required before TOP. However, if the woman is overdue for cervical screening, it may be opportunistically performed. Not part of the standard pre-TOP workup.

These confirm that the TOP is complete and detect complications early.

• Gestation: Up to ~12 weeks (optimally ≤ 10 weeks)
• What it is: A handheld 60 mL syringe creates a vacuum; attached to a cannula inserted through the cervix into the uterus
• Anaesthesia: Can be performed under local anaesthesia (paracervical block) ± conscious sedation
• Advantages: No electricity needed; portable; quiet; can be done in outpatient/clinic setting; lower cost
• Procedure:
  1. Cervical priming (misoprostol 400 μg vaginally 3h before, or mifepristone 200 mg orally 24-48h before)
  2. Paracervical block with lignocaine
  3. Gentle cervical dilation with Hegar dilators if needed
  4. Insert appropriately sized cannula
  5. Create vacuum with syringe
  6. Aspirate uterine contents with gentle rotational movements
  7. Inspect tissue — look for gestational sac, villi
  8. Send for histology

• Gestation: The most commonly used surgical method for first-trimester TOP (up to ~12-14 weeks) ^[2]
• What it is: An electric pump creates continuous suction through a cannula inserted into the uterus
• Anaesthesia: Usually general anaesthesia (in HK) or conscious sedation
• Procedure:
  1. Cervical priming — recommended for all women, especially:
     • Nulliparous women
     • Women < 18 years
     • Gestations > 10 weeks
     • Methods: misoprostol 400 μg vaginally 3h before; or osmotic dilators (laminaria/Dilapan-S) inserted 4-24h before
  2. Cervical dilation — using graduated Hegar dilators, to the appropriate size for the cannula (generally cannula size in mm ≈ gestational age in weeks)
  3. Suction aspiration — cannula attached to electric vacuum pump; systematic aspiration of all four quadrants
  4. Optional gentle sharp curettage — some operators perform a light "check curettage" to ensure completeness (though routine curettage is increasingly discouraged as it damages the basalis layer and increases Asherman syndrome risk)
  5. Inspect aspirate — float tissue in saline, identify chorionic villi macroscopically
  6. Send for histopathology

Key safety point: Failure to obtain tissue at suction termination of what appears, ultrasonically, to be an intrauterine pregnancy suggests an abnormal site of implantation, including cornual pregnancy ^[2][4].

• Gestation: Second trimester (typically > 14 weeks) ^[2]
• There remain questions as to whether dilatation and evacuation is a safe and appropriate method of terminating second trimester pregnancies when effective medical alternatives exist ^[2] — this is the lecture's explicit caution about D&E
• What it is: More extensive cervical dilation + combination of suction and forceps extraction
• Anaesthesia: General anaesthesia
• Procedure:
  1. Cervical preparation (essential — more dilation needed than first trimester):
     • Osmotic dilators (laminaria or Dilapan-S) inserted the day before (or same day for 14-16 weeks)
     • ± Mifepristone 200 mg orally 24-48h before
     • ± Misoprostol on the day
  2. Cervical dilation — up to 14-20 mm depending on gestation
  3. Evacuation — using Sopher forceps, Bierer forceps, and/or suction; fetal parts and placenta removed under ultrasound guidance
  4. Check curettage — gentle suction to ensure cavity is empty
  5. Tissue inspection — must account for all fetal parts and placenta
• Requires an experienced operator ^[2] — the risk of complications (perforation, haemorrhage, cervical laceration, retained products) is significantly higher than first-trimester procedures
• Advantage over medical TOP: Faster (single procedure, usually < 30 minutes) and more predictable timing; avoids labour-like experience
• Disadvantage: Higher surgical risk; requires general anaesthesia and experienced surgeon

• Essentially a mini-caesarean section ^[2]
• Rarely used — reserved for:
  • Failed medical and surgical TOP
  • Contraindications to other methods
  • Very late gestations with specific indications (e.g., placenta praevia precluding vaginal delivery)
• Higher morbidity — it is a major abdominal operation with all the risks of laparotomy
• Creates a uterine scar → implications for future pregnancies (risk of uterine rupture in subsequent labour)
• Almost never the first-line choice in modern practice

The non-pregnant cervix (and early pregnant cervix, especially in nulliparas) is firm, predominantly composed of collagen and smooth muscle. Rapid mechanical dilation without softening risks:

• Cervical laceration — tears in the cervical tissue, which can bleed and heal with fibrosis
• Uterine perforation — the instrument passes through the weakened or thin area
• Cervical incompetence — damage to the internal os → future pregnancies at risk of second-trimester miscarriage or preterm birth

WHO recommends cervical priming for all surgical TOPs. At minimum:

• All gestations > 12 weeks (essential)
• Nulliparous women at any gestation
• Women < 18 years
• Any woman with known cervical stenosis or previous cervical surgery

• Recommended for ALL surgical TOPs to reduce the risk of post-procedure infection (endometritis, PID)
• Regimens vary:
  • Doxycycline 100 mg PO 1h before + 200 mg PO after procedure, OR
  • Azithromycin 1g PO on the day of procedure, OR
  • Metronidazole 1g PR at time of procedure (if nil by mouth)
• In cases of septic abortion, evacuation of the uterus should be performed by experienced surgeons, optimally around one hour after intravenous antibiotics ^[2] — this is a specific scenario requiring therapeutic (not prophylactic) antibiotics:
  • Broad-spectrum IV antibiotics covering Gram-negative, Gram-positive, and anaerobes (e.g., IV cefuroxime + metronidazole + gentamicin, or piperacillin-tazobactam)
  • Evacuation performed ~1 hour after starting IV antibiotics (allows tissue antibiotic levels to rise)

• All Rh-negative women must receive anti-D within 72 hours of the procedure ^[2]
• ≤ 12 weeks: 250 IU IM
• > 12 weeks: 500 IU IM + Kleihauer-Betke test

Fertility returns rapidly after TOP (ovulation can occur within 2 weeks) ^[3]. Starting contraception immediately is critical to prevent repeat unintended pregnancy.

• Definition: Ongoing viable pregnancy after completing the medical TOP regimen (occurs in ~2-5% of cases)
• Detection: Persistent pregnancy symptoms; USS shows viable IUP with cardiac activity; β-hCG rising or plateau
• Management: Surgical evacuation (suction aspiration) — this is the definitive rescue
• Important: If the woman has taken mifepristone but then changes her mind ("reversal"), there is no proven effective "reversal" protocol. Mifepristone alone has a 40% failure rate (pregnancy may continue), but the evidence for high-dose progesterone "reversal" is very weak.

• Definition: Products of conception partially expelled/removed; retained tissue in the uterine cavity
• Presentation: Ongoing heavy bleeding, persistent cramping, open cervical os, echogenic material > 15 mm in uterine cavity on USS
• Management:
  • If asymptomatic or minimally symptomatic with small retained products: expectant management (may pass spontaneously) or repeat misoprostol (800 μg vaginal, single dose)
  • If heavy bleeding or symptomatic: surgical evacuation (suction aspiration)

When there is evidence of rapid clinical deterioration postoperatively, or in association with miscarriage, and especially when sepsis is suspected, it is vital that there is direct and rapid involvement of senior obstetric staff and other relevant specialists including intensive care doctors ^[2].

• Presentation: Fever > 38°C, foul-smelling vaginal discharge, uterine tenderness, tachycardia, hypotension
• Management:
  1. A-B-C resuscitation — IV access, bloods (FBC, CRP, blood cultures, lactate, coagulation), IV fluids
  2. IV broad-spectrum antibiotics — start IMMEDIATELY (e.g., IV amoxicillin + gentamicin + metronidazole; or piperacillin-tazobactam)
  3. Evacuation of the uterus by experienced surgeons, optimally around one hour after intravenous antibiotics ^[2]
  4. ICU referral if haemodynamically unstable or signs of septic shock
  5. Monitor for DIC (septic abortion is a recognised cause of obstetric DIC ^[11])

Laparoscopy, and/or laparotomy, is essential if perforation of the uterus occurs during suction termination of pregnancy, because of the risk of bowel damage and life-threatening sequelae ^[2][4].

• When suspected: Sudden loss of resistance during instrumentation; instrument passes further than expected; sudden pain; bleeding
• Management:
  1. STOP the procedure immediately
  2. Assess haemodynamic stability
  3. Diagnostic laparoscopy — to:
     • Confirm perforation site and size
     • Assess for bowel injury (bowel may have been sucked into the uterus through the perforation)
     • Assess for intra-abdominal haemorrhage
  4. If bowel injury found → laparotomy for repair
  5. If small uterine perforation only, no bowel injury → conservative management with observation, IV antibiotics, serial vitals
  6. If large perforation or uncontrolled bleeding → surgical repair (laparotomy, uterine repair)

• Presentation: Severe cramping within hours to days of procedure; tender, enlarged, boggy uterus; closed cervical os; minimal external bleeding
• Mechanism: Cervix clamps down → blood trapped in uterus → distension → pain + prevents myometrial contraction → more bleeding into trapped space
• Management:
  1. Re-evacuation of the uterus (suction aspiration)
  2. Uterotonics (oxytocin) post-evacuation
  3. Rapid relief of symptoms after evacuation

After the pregnancy is removed, the placental bed is a raw, vascular surface where remodelled spiral arteries previously supplied the placenta with high-volume, low-resistance blood flow. Haemostasis depends on three mechanisms:

1. Myometrial contraction — the interlacing smooth muscle fibres of the middle myometrial layer act as a "living ligature," compressing the blood vessels running through them (the same principle as in postpartum haemorrhage)
2. Local coagulation — clot formation at the vessel ends
3. Endometrial regeneration — eventually the endometrium regrows over the raw surface

If any of these mechanisms fail, bleeding continues.

1. Resuscitate: A-B-C approach; IV access ×2 large-bore; bloods (FBC, crossmatch, coagulation); IV crystalloid ± blood products
2. Identify the cause:
   • Speculum examination — cervical laceration visible? Products at the os?
   • Bimanual examination — bulky, boggy uterus (atony / retained products)? Firm, distended uterus with closed os (haematometra)?
   • Pelvic USS — retained echogenic material in the cavity?
3. Treat the cause:

   • Retained products → surgical evacuation (suction aspiration)

   • Uterine atony → uterotonics (same drugs as for PPH):

     Drug	Mechanism	Route	Notes
     Oxytocin	Oxytocin receptor agonist → myometrial contraction [3]	IV infusion (20-40 IU in 500 mL NS) or IM 5 IU	First line
     Ergometrine	Acts on α-adrenergic and serotonin receptors on smooth muscle → sustained tonic contraction	IM 0.5 mg or IV 0.25 mg (slow)	Contraindicated in hypertension, pre-eclampsia (causes vasoconstriction → hypertensive crisis)
     Misoprostol [3]	PGE1 → myometrial contraction	800 μg sublingual or 1000 μg rectal	Useful when IV access unavailable
     Carboprost (15-methyl-PGF2α) [3]	PGF2α analogue → powerful myometrial contraction	IM 250 μg, repeat q15min (max 8 doses)	Contraindicated in asthma (PGF2α causes bronchospasm)

   • Cervical laceration → direct suture repair under vision

   • Perforation → see below

   • Coagulopathy → correct with FFP, cryoprecipitate, platelets as indicated; if DIC → treat underlying cause (usually sepsis)

   • Uterine artery embolisation (UAE) ^[13] — interventional radiology option for refractory uterine bleeding unresponsive to uterotonics and surgical measures; preferred over surgery for pelvic haemorrhage due to complex anatomy ^[13]

The uterus is a muscular organ, but during pregnancy its wall is softer, more vascular, and in certain areas (e.g., the isthmus or a previous caesarean scar) may be thin. Perforation occurs when an instrument — dilator, curette, suction cannula, or forceps — passes through the full thickness of the myometrium into the peritoneal cavity.

The "give-way" sensation: When a dilator or curette meets resistance from the cervix/myometrium and then suddenly loses resistance, it indicates the instrument has penetrated through the wall. An experienced operator will feel the instrument go "further than it should."

• Fundus (most common) — the cannula passes through the thinnest part at the top of the uterus
• Isthmus / lower segment — especially at previous caesarean scar
• Lateral wall — risk of uterine vessel injury → significant haemorrhage

The perforation itself may be small and self-limiting. The danger is what happens next:

1. Bowel injury: If suction is applied after perforation, bowel loops can be drawn into the uterus through the perforation → bowel laceration, devascularisation, or transection → peritonitis → sepsis → death if unrecognised
2. Haemoperitoneum: Perforation through a vascular area → intra-abdominal bleeding → concealed haemorrhage (patient may become hypotensive without visible vaginal bleeding)
3. Bladder injury: Anterior perforation may involve the bladder (rare — the bladder sits anterior to the lower uterine segment)

Laparoscopy, and/or laparotomy, is essential if perforation of the uterus occurs during suction termination of pregnancy, because of the risk of bowel damage and life-threatening sequelae ^[2][4].

The lower genital tract (vagina, ectocervix) harbours a normal flora of bacteria. During TOP — whether medical (cervix opens, products pass through) or surgical (instruments pass through the cervix) — bacteria can ascend into the normally sterile uterine cavity. This is called ascending infection.

The risk is amplified by:

1. Retained products of conception — necrotic tissue serves as an excellent culture medium for bacteria (provides nutrients and a warm, moist environment)
2. Instrumentation — disrupts the cervical mucus barrier, introduces organisms mechanically
3. Pre-existing STI (especially Chlamydia trachomatis, Neisseria gonorrhoeae) — organisms already present in the cervix are pushed upward
4. Prolonged procedure — more time for bacterial contamination

The infection starts as endometritis (infection of the endometrium) → may spread to myometritis → parametritis (infection of the parametrium/broad ligament) → peritonitis → septicaemia/septic shock → multi-organ failure.

In cases of septic abortion, evacuation of the uterus should be performed by experienced surgeons, optimally around one hour after intravenous antibiotics ^[2][4].

When there is evidence of rapid clinical deterioration, and especially when sepsis is suspected, it is vital that there is direct and rapid involvement of senior obstetric staff and other relevant specialists including intensive care doctors ^[2][4].

The cervix is primarily composed of dense fibrous connective tissue (collagen type I and III) with some smooth muscle. Rapid, forceful mechanical dilation — especially without adequate cervical priming — can tear this tissue. The tear usually occurs at the 3 o'clock or 9 o'clock position (where the cervical branches of the uterine artery run).

• Nulliparity (firmer cervix, never dilated before)
• Inadequate cervical priming
• Forceful or rapid dilation
• Advanced gestational age (more dilation needed)
• Operator inexperience

• Immediate: Direct suture repair of the laceration under speculum visualisation; sponge forceps to tamponade bleeding; ring forceps applied to the bleeding point
• Prevention: Adequate cervical priming before ALL surgical TOPs (this is why cervical priming is so emphasised — it is the single most effective prevention strategy)

In medical TOP, the pregnancy is expelled by uterine contractions. If contractions are insufficient, or if the products are bulky or adherent, not all tissue passes. In surgical TOP, the operator may fail to evacuate the entire uterine cavity — especially if the uterus has an anomalous shape (septate, bicornuate) or contains fibroids.

Retained tissue has two consequences:

1. Prevents full myometrial contraction → ongoing bleeding
2. Serves as a nidus for infection → endometritis → septic abortion

• Pelvic USS: Echogenic material > 15 mm anteroposterior (AP) diameter in the uterine cavity is suggestive of retained products (though post-procedure appearances can be confusing — blood clot vs tissue)
• Serum β-hCG: Failure to decline suggests retained trophoblast

• Asymptomatic, small remnant: Expectant management (may pass spontaneously) or repeat dose of misoprostol 800 μg vaginally
• Symptomatic (heavy bleeding / infection): Surgical evacuation (suction aspiration)
• Products visible at the cervical os: Remove with sponge forceps — a simple bedside manoeuvre that can be immediately effective

After evacuation, the cervix can go into reflex spasm and close tightly (especially if cervical priming was inadequate). Meanwhile, the placental bed continues to ooze blood. With the os closed, blood accumulates inside the uterus. The uterus distends, but distension actually worsens the bleeding because:

• A distended uterus cannot contract effectively (Laplace's law — wall tension is proportional to radius; a dilated uterus needs more force to generate the same contraction pressure)
• Compressed venous drainage from the distended uterus further congests the placental bed

This creates a vicious cycle: blood accumulates → uterus distends → less contraction → more blood accumulates.

• Re-evacuation of the uterus — suction aspiration; as soon as the cannula enters the uterus, dark blood gushes out and the patient experiences immediate relief
• Uterotonics post-evacuation (oxytocin) to maintain contraction and prevent re-accumulation

• Medical: The mifepristone-misoprostol regimen fails to completely detach and expel the pregnancy. The embryo remains implanted and viable. Risk factors include very early gestation ( < 6 weeks — the sac is very small and may be missed), obesity (reduced misoprostol absorption), and fibroids (altered uterine contractility).
• Surgical: The operator fails to aspirate the gestational sac — either because it is very small (early pregnancy) or because the uterus has an anomaly (e.g., one horn of a bicornuate uterus is not evacuated)

• Persistent pregnancy symptoms (nausea, breast tenderness)
• No or minimal bleeding after medical TOP
• Rising or plateauing β-hCG
• USS shows viable IUP with fetal cardiac activity

• Surgical evacuation — definitive treatment
• Counselling: The woman must be informed that if she chooses to continue the pregnancy after exposure to mifepristone, there is uncertain but possible teratogenic risk (data is limited; mifepristone is classified as a potential teratogen, though evidence of specific anomalies in continuing pregnancies is inconsistent)

"Asherman" = Joseph Asherman, who described the syndrome in 1948.

The endometrium has two layers:

1. Functionalis — the superficial layer that sheds during menstruation and is rebuilt each cycle
2. Basalis — the deep layer that contains stem cells responsible for regenerating the functionalis

During surgical evacuation, if the basalis layer is damaged (by excessive or aggressive curettage), the regenerative capacity is lost. Instead of regrowing normal endometrium, the denuded areas on opposing uterine walls heal by forming fibrous adhesions (scar tissue bridges) across the cavity. These adhesions:

• Physically obliterate parts of the uterine cavity
• Reduce the functional endometrial surface area
• Block the internal os or tubal ostia

• Hysteroscopy (gold standard) — direct visualisation of adhesions within the uterine cavity; also therapeutic (adhesions can be divided at the same time)
• Hysterosalpingography (HSG) ^[13] — shows filling defects within the uterine cavity and may show blocked fallopian tubes (used for investigation of infertility and recurrent abortion) ^[13]
• Saline infusion sonohysterography (SIS) — saline instilled into the uterus under USS → adhesions visible as bands
• USS: May show thin endometrium, but not specific

• Hysteroscopic adhesiolysis — division of adhesions under direct vision (the treatment of choice)
• Post-operative measures to prevent re-formation:
  • Intrauterine balloon catheter (Foley catheter with balloon inflated in the cavity) left for 5-7 days → acts as a physical spacer preventing the walls from re-adhering
  • Exogenous oestrogen (high-dose oestradiol) for 2-3 months → stimulates endometrial regeneration over the denuded areas
  • Repeat hysteroscopy to assess and divide any re-formed adhesions

If the cervix is traumatised during TOP (forceful dilation, cervical laceration), the internal os may be permanently weakened. In a subsequent pregnancy, this weakened cervix cannot withstand the increasing weight and pressure of the growing fetus → painless cervical dilation in the second trimester → preterm delivery or second-trimester miscarriage.

• More common after repeated first-trimester surgical TOPs or second-trimester D&E (which requires significant dilation)
• The association between a single, uncomplicated first-trimester TOP and cervical incompetence is debated and probably very small — but repeated procedures or traumatic procedures definitely increase risk

• Cervical cerclage — a suture placed around the cervix (usually at 12-14 weeks) to keep it closed; removed at 36-37 weeks or at onset of labour
• Progesterone supplementation — vaginal progesterone from mid-trimester to reduce preterm birth risk

If anti-D immunoglobulin is NOT administered to an Rh-negative woman undergoing TOP:

1. Fetomaternal haemorrhage occurs during the procedure (fetal Rh-positive red cells enter maternal circulation)
2. Maternal immune system recognises the D antigen as foreign → produces anti-D IgG antibodies (primary sensitisation — takes ~4-6 weeks)
3. In a subsequent pregnancy with an Rh-positive fetus, these pre-formed anti-D IgG antibodies cross the placenta → bind to fetal Rh-positive red cells → opsonise them for destruction by fetal reticuloendothelial system → haemolytic disease of the fetus and newborn (HDFN):
   • Fetal anaemia → high-output cardiac failure → hydrops fetalis
   • Severe neonatal jaundice (unconjugated bilirubin from haemolysis) → kernicterus (bilirubin encephalopathy)

• Anti-D immunoglobulin to ALL Rh-negative women within 72 hours of TOP ^[2]
• This is one of the most important preventive measures in obstetric practice — failure to administer anti-D is a recognised medicolegal pitfall

• The majority of women do NOT experience clinically significant long-term psychological harm after TOP
• The best predictor of post-TOP mental health is pre-TOP mental health — women with pre-existing depression or anxiety are at higher risk of psychological distress after TOP
• Outline of emotional impact on the couple with early pregnancy losses ^[5] — the lecture explicitly acknowledges the emotional dimension

• Pre-procedure and post-procedure non-directive counselling — essential component of care ^[2]
• Screening for pre-existing mental health conditions
• Referral to psychological services if distress persists
• Follow-up visit to check emotional well-being in addition to physical recovery

Pregnancy itself is a hypercoagulable state (elevated fibrinogen, factors VII, VIII, X, von Willebrand factor; decreased protein S; increased venous stasis from progesterone-mediated venous dilation and uterine compression of pelvic veins). Although TOP removes the pregnancy, the coagulable state does not immediately normalise. Additionally:

• Immobilisation during/after the procedure
• Pelvic surgery (surgical TOP involves instrumentation near pelvic veins)
• Oral contraceptive use ^[15] — if OCP was the failed contraceptive or is started immediately post-TOP, it adds VTE risk (OCP increases VTE risk 2-4× ^[15])

• The absolute risk of VTE after TOP is very low (< 0.05%)
• Higher risk: second-trimester procedures, prolonged immobilisation, obesity, thrombophilia, previous VTE
• Thromboprophylaxis (LMWH) is NOT routine for straightforward first-trimester TOP in low-risk women
• Consider thromboprophylaxis for: BMI > 30, previous VTE, known thrombophilia, prolonged procedure/immobilisation