L23: Antepartum Hemorrhage (APH)

Definition & Major Causes
  • Definition: This is defined as vaginal bleeding from ≥ 24 weeks of gestation until the onset of labour. Any APH must always be taken seriously; it is an Obstetrical Emergency.
  • Incidence: 2-5% of pregnancies.
  • Main Causes:
    • Unexplained APH (80%): Often due to marginal placental bleed.
    • Placental Causes (2/3 of specific causes): Placental Abruption (1/3) and Placenta Previa (1/3).
    • Fetal Causes: Vasa Previa (bleeding is purely fetal, catastrophic for the fetus).
    • Local Causes: Cervicitis, Cervical ectropion, Cervical carcinoma, Vaginal trauma, Vaginal infection.
Maternal & Fetal Assessment
  • History of APH includes: Dates/previous US, amount of bleeding, pain, coitus, trauma, leaking fluid, previous uterine surgery, smoking/drugs, fetal movements, blood group, position of placenta.
  • Maternal Assessment: Pulse rate, Blood pressure, Uterine palpation for size, tenderness, and presenting part.
  • Golden Rule: NO VAGINAL EXAMINATION (NO PV) should be done until Placenta Previa is absolutely excluded!
  • Fetal Assessment: Ensure the heart rate heard is fetal, not maternal (the mother may be very tachycardic). If the gestational age is ≥ 26 weeks and the fetal heart is heard, electronic Fetal Heart Rate Monitoring (CTG) should be performed.
Major Hemorrhage & Resuscitation (ABC)
  • Major Hemorrhage Definition: Blood loss > 1000 ml, systolic BP < 100 mmHg, pulse > 120 bpm, reduced peripheral perfusion, or disturbance of consciousness state.
  • Pathophysiology of Blood Volume: Pregnant women tolerate 500-1000 mL (10-15%) loss well due to compensatory mechanisms until 30-40% is lost. Uterine blood flow at term is 500-800 mL/min (Placental circulation = 400 mL/min), meaning rapid massive loss can occur very quickly.
  • Initial Resuscitation (A, B, C):
    • Call for help: Alert senior obstetrician, anesthetist, hematologist, blood bank, and theatres.
    • Position: Left lateral tilt (30°) if antepartum, to relieve venocaval compression and improve venous return.
    • Airway/Breathing: High-flow facial oxygen (regardless of oxygen saturation). Assess airway; intubation indicated if decreased consciousness.
    • Circulation: Two large-bore IV cannulae (14 gauge - Orange). Take blood for FBC, cross-match, U&Es, LFTs, coag screen. Start IV crystalloids to correct hypovolemia.
    • Blood Transfusion: Give O Rhesus-negative (O-) blood immediately until cross-matched blood is available.
    • Clotting Factors: Fresh Frozen Plasma (FFP) -> 1 Unit FFP for every 1 Unit of blood once 2 Units given. Consider cryoprecipitate/platelets.
    • Catheterization: Catheterize and measure hourly urine output. Assess need for CVP line.
Placenta Previa & Placenta Accreta Spectrum
  • Placenta Previa (PP): Placenta implants in the lower uterine segment, over or near the internal os. (Latin 'previa' = going before the fetus).
    • New Classification: 1. Placenta Previa: Internal os covered partially or completely. 2. Low-lying placenta: Edge lies within a 2-cm wide perimeter around the os, but does not cover it.
    • Risk Factors: Multiple gestation, previous Cesarean section, uterine structural anomaly, assisted conception.
    • Warning Sign: Painless vaginal bleeding.
    • Management: Depends on fetal maturity, bleeding severity, and associated labour. Resuscitate (ABC). Admit for observation if minor bleed (minimum 24h). Admit inpatients from 34 weeks if major PP with recurrent bleeding. Avoid non-indicated Cesarean Section as a preventative measure.
  • Placenta Accreta Spectrum (PAS): Abnormally implanted, invasive, or adhered placenta. (Also called Morbidly adherent placenta MAP or Abnormally invasive placenta AIP).
    • Classification: Accreta: attached to myometrium. Increta: invades myometrium. Percreta: penetrates through myometrium to serosa/adjacent organs (e.g. bladder).
    • Diagnosis: Doppler Ultrasound and MRI.
    • Maternal Risks: Shock, renal failure, operative complications (bladder/ureter injury), massive transfusion needs, loss of fertility, mortality.
    • Management: Tertiary center referral with surgical, anesthesia, ICU, and urological consultants available.
💡 Key Hints for L23 (APH)
  • Hint 1: NEVER perform a digital vaginal examination (PV) in a patient with APH until Ultrasound firmly excludes Placenta Previa.
  • Hint 2: Placental blood flow is 400 mL/min; hemorrhage can become fatal in minutes. Always use 14-gauge cannulas.
  • Hint 3: The definitive presentation of Placental Abruption is a tender, hard (woody) uterus with or without vaginal bleeding (concealed vs revealed), often showing fetal tachycardia or late decelerations on CTG.
  • Hint 4: For immediate uncrossmatched transfusion in severe APH, use O Rhesus-negative blood.
  • Hint 5: In PAS (Accreta/Increta/Percreta), MRI is highly valuable alongside Doppler US to assess depth of invasion before surgery.

L24: Preterm Labour (PTL)

Definition, WHO Classification & Causes
  • Definition: Onset of labor before 37 weeks' gestation (between 24+0 and 36+6 weeks).
  • WHO Categories: Moderate to late preterm (32+0 to 36+6), Very preterm (28+0 to 31+6), Extreme preterm (24+0 to 27+6).
  • Main problems for preterm babies: Respiratory distress syndrome, Chronic lung disease, Intraventricular hemorrhage, Periventricular leukomalacia, Infection, Hypoglycemia, Necrotizing enterocolitis (NEC), Patent ductus arteriosus, Jaundice.
  • Causes/Risk Factors:
    • Uterine distension: Multiple pregnancy (rises with fetal number) and Polyhydramnios.
    • Uterine Müllerian anomalies: Occur in up to 4% of women.
    • Hemorrhage: APH and Subchorionic hematoma. Acute bleeding releases thrombin which directly stimulates myometrial contractions.
Prediction & Assessment of PTL
  • Prediction Tools:
    • 1. Past Obstetric History: Previous PTL increases the risk four-fold (not useful in a first pregnancy).
    • 2. Ultrasound: Measurement of cervical length.
    • 3. Fetal Fibronectin (fFN): Normally found >50 ng/mL up to 20 weeks and after 36 weeks. The presence of fFN at levels > 50 ng/mL between 20 and 36 weeks is NOT normal and predicts a high risk of PTL. Note: fFN testing becomes negative if membranes are ruptured >12 hours.
  • Clinical Assessment: Check dating, ask about pain/contractions/fluid loss. Check maternal vitals and uterine tenderness.
  • Speculum exam: Look for blood, discharge, liquor, take swabs. Avoid digital PV if PPROM suspected.
Prevention & Management (Cerclage & Tocolytics)
  • Prevention in high-risk: Progesterone and Cervical Cerclage. (Note: neither appears to reduce risk in multiple pregnancies). Other methods: Cervical pessary, selective fetal reduction, aspirin, treating Bacterial Vaginosis (BV).
  • Cervical Cerclage Types & Indications: Provides structural support and enhances immunological barrier by retaining mucous plug.
    • 1. History-indicated: Prophylactic in asymptomatic women, inserted at 12-14 weeks. Indication: >2 previous preterm births or 2nd-trimester losses. Must do US for viability/anomaly before insertion.
    • 2. Ultrasound-indicated: History of cervical surgery/loss AND cervix is ≤ 25 mm before 24 weeks.
    • 3. Rescue cerclage: When cervix is dilating WITHOUT contractions.
    • Types: McDonald (transvaginal purse-string without bladder mobilization), Shirodkar (transvaginal with bladder mobilization for higher placement), Transabdominal (via laparotomy, requires 2 laparotomies total as delivery must be CS. Used if vaginal fails or extensive cervical surgery).
    • Absolute Contraindications for Cerclage: Active preterm labour, Clinical chorioamnionitis, Continuing vaginal bleeding, PPROM, Fetal compromise, Lethal fetal defect, Fetal death.
  • Management of established PTL: Up to 70% of threatened PTL cases settle spontaneously.
    • Tocolytics: Used strictly to delay delivery for 48h to allow corticosteroids (for lung maturity) or in-utero transfer. (e.g. Nifedipine, Atosiban).
    • Magnesium Sulfate (MgSO4): Administered for fetal neuroprotection (prevents cerebral palsy) if delivery is imminent < 32 weeks.
💡 Key Hints for L24 (PTL)
  • Hint 1: Fetal Fibronectin (fFN) is an excellent negative predictor. Value > 50 ng/mL between 20-36w is abnormal.
  • Hint 2: Multiple pregnancy and polyhydramnios cause PTL mechanically via uterine distension.
  • Hint 3: Hemorrhage causes PTL chemically because the breakdown product Thrombin directly stimulates myometrial contraction.
  • Hint 4: Transabdominal cerclage mandates delivery by Cesarean Section.
  • Hint 5: Never place a cervical cerclage in cases of active contractions, active bleeding, or clinical chorioamnionitis.

L25: Premature Rupture of Membranes (PROM / PPROM)

Definition & Risk Factors
  • Definition: Rupture of membranes before the onset of labor. Preterm PROM (PPROM) happens before 37 weeks and complicates up to 3% of pregnancies.
  • Risk Factors: Recurrent PPROM, weak cervix (fails as ascending infection barrier and allows membrane prolapse), and Maternal Smoking (dose-dependent).
  • Risks to Mother: Infection (endometritis, sepsis), Placental abruption, CS.
  • Risks to Fetus: Prematurity, Infection, Pulmonary hypoplasia, Limb contractures, Cord prolapse.
Clinical Assessment & Diagnosis
  • History: "Gush of fluid" followed by dampness identifies over 90% of cases. Rule out urine, excessive discharge (BV), or cervical mucus.
  • Examination: Check maternal temperature, HR, uterine tenderness. Fetal tachycardia is used in defining clinical chorioamnionitis.
  • Sterile Speculum: Best done after resting supine for 20-30 mins. Look for pooling in posterior fornix. DIGITAL EXAMINATION MUST BE AVOIDED as it increases chorioamnionitis, postpartum endometritis, neonatal infection, and decreases the latent period before labor onset.
  • Presence of Meconium: At preterm, suggests intra-amniotic infection. At term, it is a relative contraindication to expectant management.
  • Diagnostic Tests:
    • Nitrazine sticks: Tests alkaline pH. 17% False positive (urine, blood, semen).
    • Ferning pattern: Due to NaCl/protein. 6% False positive (cervical mucus).
    • Advanced Biochemical Tests: IGFBP-1 or PAMG-1. PAMG-1 has high sensitivity (96%) and specificity (98.9%).
    • Gold Standard: Amnio-dye test.
Management & Chorioamnionitis
  • Term PROM (≥37 wks): Outcomes for immediate induction are as good as conservative. Induce immediately if colonized with Group B Streptococcus (GBS). Early induction reduces perinatal infection without increasing CS rates.
  • PPROM (<37 wks): Expectant conservative management until 37 weeks unless chorioamnionitis or contraindications.
    • Tocolysis: NOT recommended.
    • Antibiotics: Erythromycin 250 mg orally 4 times daily for 10 days (or Penicillin) is the drug of choice. Avoid Co-amoxiclav as it increases neonatal Necrotising Enterocolitis (NEC).
    • Corticosteroids & MgSO4 are offered.
  • Clinical Chorioamnionitis Criteria: Maternal pyrexia >38°C PLUS at least TWO of: maternal tachycardia (>100 bpm), fetal tachycardia (>160 bpm), uterine tenderness, raised CRP, offensive vaginal discharge.
  • Pre-viable PROM (< 24 weeks): Significant risk of lethal pulmonary hypoplasia, limb contractures, and extreme morbidity. Many parents opt for termination of pregnancy. Minimally invasive sealants have proved disappointing.
💡 Key Hints for L25 (PROM)
  • Hint 1: A history of a 'gush of fluid' is highly reliable (>90%).
  • Hint 2: Digital vaginal exam is absolutely contraindicated in PPROM unless labor is actively established, to prevent severe infections.
  • Hint 3: Co-amoxiclav is dangerous in PPROM; it causes neonatal NEC. Use Erythromycin instead for 10 days.
  • Hint 4: Pre-viable PROM (<24 weeks) severely hinders lung development, causing lethal pulmonary hypoplasia.
  • Hint 5: Maternal fever >38°C + Fetal tachycardia >160 bpm = highly suspicious for Chorioamnionitis.

L26: Aberrant Liquor Volume

Amniotic Fluid Physiology & Assessment
  • Functions: Protects fetus, permits movement preventing limb contracture, prevents adhesions, permits lung development (2-way movement into bronchioles), contains growth factors/stem cells.
  • Volume Dynamics: Increases progressively (30ml at 10w, 600ml at 30w, peak 1000ml at 38w), then rapid fall (800ml at 40w, 350ml at 42w).
  • Assessment (Ultrasound is standard, clinical palpation unreliable):
    • Single Deepest Pocket (SDP / MVP): Deepest vertical pocket excluding cord/fetal parts. < 2 cm = Oligohydramnios, > 8 cm = Polyhydramnios.
    • Amniotic Fluid Index (AFI): Sum of 4 quadrants (divided by linea nigra and umbilicus). Normal is 10 to 25 cm. < 5 cm = Oligohydramnios, ≥ 25 cm = Polyhydramnios.
Oligohydramnios & Anhydramnios
  • Definition: MVP < 2 cm, AFI < 5 cm, or volume < 200-500 mL.
  • Clinical presentation: History of clear fluid leak. Uterus small for dates, fetal poles felt 'hard' and obvious.
  • Causes:
    • Too little production: Renal agenesis (no renal tissue/bladder on US), Multicystic kidneys, Urinary tract obstruction.
    • Placental insufficiency: Fetal Growth Restriction (FGR), pre-eclampsia.
    • Drugs: NSAIDs (Non-Steroidal Anti-Inflammatory Drugs cause fetal oliguria).
    • Post-dates pregnancy (>40 weeks).
    • Leakage: PPROM (diagnosed by speculum).
  • Complication: Absence of amniotic fluid in 2nd trimester causes Pulmonary Hypoplasia.
Polyhydramnios
  • Definition: SDP > 8 cm, AFI ≥ 25 cm. Affects 1-2% of pregnancies.
    • Mild: AFI 25-29.9 cm. Moderate: AFI 30-34.9 cm. Severe: AFI ≥ 35 cm (DVP >15cm).
  • Clinical signs: Severe abdominal swelling/discomfort. Abdomen distended out of proportion (increased SFH), tense and tender, fetal poles hard to palpate. Abdominal girth round umbilicus is more than normal.
  • Causes:
    • Maternal: Diabetes Mellitus (requires GTT), Placental Chorioangioma, Arteriovenous fistula.
    • Fetal: Multiple gestation (Twin-to-Twin Transfusion Syndrome in monochorionic), Idiopathic, Oesophageal/Duodenal atresia (associated with Trisomy 21), Neuromuscular conditions (preventing swallowing), Anencephaly, Congenital infections (TORCH).
  • Complications: Preterm delivery (uterine stretch), malpresentation, maternal discomfort.
  • Management: Establish cause (GTT, serology, detailed US). Relieve discomfort (Amniodrainage). NSAIDs can be used to reduce fluid but require close supervision as they cause premature closure of ductus arteriosus and fetal oliguria. If lie is unstable at term -> admit -> CS if labor starts. DM polyhydramnios corrects itself with optimal maternal glycaemic control.
💡 Key Hints for L26 (Liquor Volume)
  • Hint 1: AFI < 5cm = Oligo. AFI > 25cm = Poly. SDP < 2cm = Oligo. SDP > 8cm = Poly.
  • Hint 2: The fetus swallows amniotic fluid and urinates it. Swallowing block (Esophageal/Duodenal atresia) = Polyhydramnios. Urine block (Renal agenesis) = Oligohydramnios.
  • Hint 3: NSAIDs reduce amniotic fluid (used to treat poly, but can cause oligo and close the fetal ductus arteriosus).
  • Hint 4: Unexplained Polyhydramnios? Always test for Maternal Diabetes (GTT) and Fetal structural anomalies.
  • Hint 5: Normal fluid at 38 weeks is ~1000ml, but rapidly drops to ~350ml by 42 weeks (post-dates oligohydramnios).

L27: Obstetric Emergencies

Maternal Collapse & AFE
  • Maternal Collapse Causes: Massive APH/PPH, Eclampsia, VTE, AFE, Sepsis, Uterine inversion/rupture.
  • Initial Management:
    • ABCDE Approach: Same as non-pregnant. Remember to use Left Lateral tilt to minimize aorto-caval compression.
    • Disability: Glasgow Coma Scale. GCS ≤ 8 indicates compromised airway and requires Intubation.
    • Exposure: Risk of hypothermia.
    • Perimortem CS: Must deliver fetus rapidly to save the mother if CPR is ongoing.
  • Amniotic Fluid Embolism (AFE):
    • Risk Factors: Medical induction of labor, multiple pregnancy, older age, CS/instrumental delivery, polyhydramnios, abruption, cervical laceration, uterine rupture.
    • Diagnosis: Clinical diagnosis of exclusion (exclude PE, anaphylaxis, sepsis, eclampsia, MI).
    • Prognosis: Very poor. ~30% die in 1st hour, only 10% survive overall. Management is ABC.
Uterine Emergencies (Inversion & Rupture)
  • Uterine Inversion:
    • Degrees: 1st (fundus at cervix), 2nd (through cervix into vagina), 3rd (outside vagina), 4th (total inversion including vagina).
    • Risk Factors: Strong traction on umbilical cord with excessive fundal pressure, abnormal placental adherence, anomalies, short cord, fetal macrosomia, Marfan/Ehlers-Danlos syndromes.
    • Signs: Hemorrhage (94%), severe 3rd stage pain, Neurogenic shock out of proportion to blood loss (increased vagal tone), fundus not palpable abdominally.
    • Management: Call help, ABC. Johnson Manoeuvre (immediate manual replacement pushing fundus through cervix). Do NOT remove placenta until replaced! Use tocolytics (Terbutaline) or volatile anesthetics to relax uterus. If manual fails -> O'Sullivan's technique (hydrostatic repositioning).
  • Uterine Rupture:
    • Classification: Complete (full thickness + peritoneum), Incomplete/Dehiscence (visceral peritoneum intact, asymptomatic).
    • Causes: Previous CS (lower segment 0.9%, classical 3-6%), myomectomy, oxytocics (PGE2, misoprostol), obstructed labor, obstetric manipulation.
    • Signs: Cessation of uterine contractions, FHR abnormalities (tachycardia, late/variable decelerations - most reliable early signs), lower abdominal pain (Bandl's ring in obstructed), loss of station, easily palpated fetal parts (two swellings), vaginal bleeding.
    • Management: Immediate laparotomy (Repair, Repair + tubal ligation, Subtotal/Total Hysterectomy).
    • Prevention: Avoid vaginal delivery after breached myomectomy. Caution with induction in VBAC.
Cord Prolapse & Impacted Head
  • Cord Prolapse: Descent of cord alongside/past presenting part with ruptured membranes. (If membranes intact = cord presentation).
    • Management: Speculum/digital exam immediately. Relieve compression by elevating presenting part manually or catheterize and fill bladder with 500 mL normal saline (clamp catheter, unclamp before CS!). Position mother in knee-elbow or left lateral with Trendelenburg. AVOID handling the cord to prevent spasm. Immediate CS (Urgency Grade 1 if abnormal FHR).
  • Impacted Head at CS: Highly stressful emergency.
    • Risk factors: Full dilatation CS, malpresentations, prolonged 2nd stage, intravenous Syntocinon prior to CS, unsuccessful instrumental delivery.
    • Management: Consultant presence required. Assistant can flex/rotate head vaginally. Devices like C-Snorkel can release vacuum. Extreme care to avoid iatrogenic trauma. Prevention: avoid amniotomy if head not fixed in pelvis.
💡 Key Hints for L27 (Emergencies)
  • Hint 1: Fetal heart rate abnormalities (bradycardia, late decels) are the *first* and most reliable sign of uterine rupture.
  • Hint 2: Shock out of proportion to blood loss in the 3rd stage of labor points to Uterine Inversion (Neurogenic shock).
  • Hint 3: GCS ≤ 8 is the universal threshold for intubating a collapsed pregnant patient.
  • Hint 4: When pushing back a prolapsed cord, fill the bladder with 500ml saline to lift the baby's head, but *must* drain it before making the CS incision.
  • Hint 5: Pulling the umbilical cord strongly before placental separation is the classic iatrogenic cause of uterine inversion.

L28: Venous Thromboembolism (VTE)

Risks & Diagnosis of VTE
  • Pregnancy is associated with a 6-10 fold increased risk of VTE. Incidence peaks post-partum and is further increased following emergency CS.
  • Thrombophilia: Hereditary (Protein C, S, Antithrombin III deficiency, Factor V Leiden, Prothrombin G20210A mutation). Causes recurrent fetal loss.
  • Risk Factors: Age >35, BMI > 30, Parity ≥ 3, smoking, severe varicose veins, paraplegia, multiple gestation, CS, prolonged labor (>24h), Hyperemesis, IVF, systemic infection.
  • Diagnosis: Clinical diagnosis is unreliable.
    • Deep Vein Thrombosis (DVT): Unilateral calf pain/swelling/redness. Compression Ultrasound is the first investigation. Venography is invasive but excellent.
    • D-Dimer: Elevated physiologically in pregnancy, limiting its usefulness. It retains negative predictive value but is NOT a reliable diagnostic test in pregnancy.
Treatment & Prevention of VTE
  • Low-Molecular-Weight Heparin (LMWH): Treatment of choice. Does not cross placenta, safe, less bleeding risk. Patients self-inject.
  • Warfarin: Teratogenic (crosses placenta, causes facial/limb defects in 1st trimester, ICH in 2nd/3rd). Used rarely (e.g., mechanical heart valves). Safe during breastfeeding.
  • Newer anticoagulants (Fondaparinux, Lepirudin) are NOT licensed in pregnancy/breastfeeding.
  • Graduated elastic stockings should be worn for 2 years to prevent post-thrombotic syndrome.
  • Prophylaxis Guidelines (RCOG): High risk requires antenatal LMWH prophylaxis. Four or more risk factors: prophylaxis from 1st trimester. Three risk factors: from 28 weeks. Postnatal: at least 10 days for intermediate risk, 6 weeks for high risk.
Antiphospholipid Syndrome (APS) & Thrombocytopenia
  • APS (Hughes Syndrome): Lupus anticoagulant (inhibitor of coagulation pathway) and anticardiolipin antibodies.
    • Clinical Criteria: Vascular thrombosis OR ≥3 consecutive miscarriages (<10 wks) OR ≥1 fetal death (>10 wks) OR ≥1 preterm delivery due to pre-eclampsia/insufficiency.
    • Laboratory Criteria: Anticardiolipin IgG/IgM or Lupus Anticoagulant positive on two occasions > 6 weeks apart.
    • Treatment: Aspirin when pregnancy confirmed + LMWH when fetal heart is seen. (Boosts take-home baby rate from 40% to 70%).
  • Thrombocytopenia: Platelets < 150 × 10^9/L.
    • Gestational Thrombocytopenia is common (7-8%). Modest drop (100-150) is safe. Bleeding is rare unless platelets < 50 × 10^9/L.
    • Management: Epidural/spinal anesthesia should be AVOIDED if platelets < 80 × 10^9/L. Fetal blood sampling and instrumental delivery avoided due to risk of neonatal hematoma.
💡 Key Hints for L28 (VTE)
  • Hint 1: LMWH is the absolute gold standard for VTE in pregnancy because it does not cross the placenta.
  • Hint 2: Warfarin is highly teratogenic but is surprisingly completely safe during breastfeeding.
  • Hint 3: Never rely on a positive D-Dimer to diagnose VTE in pregnancy; it is naturally high. Use Compression US for DVT.
  • Hint 4: APS diagnosis strictly requires lab tests to be positive twice, at least 6 weeks apart.
  • Hint 5: Anesthetists will refuse an Epidural if maternal platelets drop below 80,000 due to risk of spinal hematoma.

L29: Fetal Growth Restriction (FGR)

FGR vs SGA & Aetiology
  • Fetal Growth Restriction (FGR): Failure of fetus to achieve its genetic growth potential. Carries risk of intrapartum asphyxia, stillbirth, and long-term cardiovascular disease.
  • Small for Gestational Age (SGA): Fetal weight < 10th centile. Most SGA fetuses are constitutionally small and completely healthy. Not all SGA are FGR, and not all FGR are SGA!
  • Aetiology:
    • Reduced growth potential: Single gene defects (Seckel syndrome), Structural abnormalities (Renal agenesis), Intrauterine infections (CMV, Toxoplasmosis).
    • Reduced growth support (Maternal): Undernutrition, Hypoxia (cyanotic heart disease, high altitude), Drugs (smoking, cocaine, alcohol).
    • Reduced growth support (Placental): Reduced uteroplacental perfusion (pre-eclampsia, antiphospholipid syndrome, sickle cell).
Management & Surveillance
  • Initial Investigation: Comprehensive US anatomy scan.
    • Symmetrical FGR + Normal Liquor: Highly suspicious of fetal genetic defect. Offer Amniocentesis and rapid fetal karyotyping.
    • Asymmetrical FGR (small AC) + Oligohydramnios + High Umbilical Artery Resistance: Indicates Uteroplacental Insufficiency.
  • Surveillance: Serial biometry and AFV every 2 weeks.
    • Doppler Studies: Umbilical artery waveform. Absence or reversed flow during diastole indicates severe compromise and requires delivery in the near future.
  • Treatment: There is NO effective medical treatment. Management involves appropriate monitoring and timely delivery.
💡 Key Hints for L29 (FGR)
  • Hint 1: Asymmetrical FGR = Placental problem (brain-sparing effect preserves head size, but abdomen is small).
  • Hint 2: Symmetrical FGR = Intrinsic fetal problem (genetic or early TORCH infection).
  • Hint 3: Absent or reversed end-diastolic flow on Doppler means the placenta is failing drastically -> Prepare for urgent delivery.
  • Hint 4: Smoking and Cocaine use directly cause reduced maternal growth support.
  • Hint 5: You cannot "cure" FGR medically. The only management is close monitoring and deciding the optimal time for delivery.

L30: Obstetric Analgesia and Anesthesia

Ideal Analgesic & Non-Pharmacological Methods
  • Ideal Analgesic: Good pain relief, easy to administer, safe for mother/baby, reversible, does NOT interfere with uterine contractions, does not affect mobility.
  • Water birth: Water should not exceed 37.5°C.
  • Transcutaneous Electrical Nerve Stimulation (TENS): Works by blocking pain via 'gate theory'. Useful in latent phase. Ineffective in established labor. Has no adverse effects.
Epidural Anesthesia
  • Effects on Labor: Does NOT increase Cesarean section rates. However, it prolongs the second stage and increases the chance of instrumental delivery.
  • Indications: Prolonged labor, oxytocin augmentation, maternal hypertension, multiple pregnancy, high risk for operative intervention.
  • Contraindications: Coagulation disorders (low platelets), Local/systemic sepsis, Hypovolemia, Logistical (no trained staff).
  • Complications: Spinal hematoma (rare), Infection (Meningitis/Abscess), Toxicity.
    • Accidental Total Spinal Anesthesia: Injection of epidural doses into the subarachnoid space causes severe hypotension, respiratory failure, unconsciousness, and death if untreated.
  • Technique: Left lateral or sitting flexed position to open lumbar spaces.
General Anesthesia (GA)
  • Usage & Risk: Used for emergencies when regional is contraindicated. The great majority of direct anesthetic-related maternal deaths are associated with emergency general anesthesia. RCOG recommends >85% of emergency CS be under regional.
  • Patient Preparation for GA:
    • Antacids: To prevent aspiration pneumonitis (Mendelson's syndrome).
    • Lateral Uterine Displacement (LUD): To prevent supine hypotension.
    • Preoxygenation.
  • High-Risk Patient for GA: Marked obesity, Severe edema (face/neck), Abnormal dentition/small mandible, Extremely short stature/neck, Goiter, Severe pre-eclampsia, Bleeding disorders.
💡 Key Hints for L30 (Analgesia)
  • Hint 1: Epidurals increase forceps/ventouse delivery rates but DO NOT increase C-Section rates.
  • Hint 2: TENS is only effective in early/latent labor, it fails during active strong contractions.
  • Hint 3: Avoid Epidural entirely if the patient is hypovolemic (e.g. bleeding from APH) as it causes massive vasodilation and fatal hypotension.
  • Hint 4: Total Spinal Anesthesia is a catastrophic complication of Epidural causing instant respiratory failure.
  • Hint 5: Preoxygenation, Antacids, and Left Lateral Tilt are mandatory before General Anesthesia in a pregnant woman.

Top 5 Crucial Comparisons

1. Placenta Previa vs. Placental Abruption
Feature Placenta Previa (PP) Placental Abruption
Bleeding Type Painless, bright red Painful, dark red (often concealed)
Uterus Palpation Soft, non-tender, relaxed Hard (woody), tense, severely tender
Fetal Heart Rate Usually normal (unless severe shock) Abnormal (Tachycardia, late decelerations)
Vaginal Exam (PV) ABSOLUTELY CONTRAINDICATED Done only after PP is excluded by US
Risk Factors Previous CS, multiple gestation Hypertension/Pre-eclampsia, trauma, cocaine
2. Oligohydramnios vs. Polyhydramnios
Feature Oligohydramnios Polyhydramnios
Amniotic Fluid Index (AFI) < 5 cm ≥ 25 cm
Single Deepest Pocket (SDP) < 2 cm > 8 cm
Fetal Causes Renal agenesis, Multicystic kidneys, FGR Oesophageal/Duodenal atresia, Anencephaly
Maternal Causes PPROM, NSAIDs use, Post-dates Diabetes Mellitus
Clinical Presentation Small SFH, fetal parts easily felt Large SFH, tense abdomen, hard to feel fetus
3. Fetal Growth Restriction (FGR) vs. Small for Gestational Age (SGA)
Feature SGA (Small for Gestational Age) FGR (Fetal Growth Restriction)
Definition Weight < 10th centile for gestational age Failure to achieve genetic growth potential
Health Status Usually constitutionally small & healthy Compromised, high risk of asphyxia/stillbirth
Doppler Ultrasound Normal umbilical artery blood flow Abnormal (e.g. absent/reversed end-diastolic flow)
Amniotic Fluid Usually normal Often Oligohydramnios (if asymmetrical)
4. Types of Cervical Cerclage
Type Indication & Timing Technique Detail
History-indicated Prophylactic (12-14 weeks). >2 previous preterm births. McDonald or Shirodkar (transvaginal)
Ultrasound-indicated Cervix ≤ 25 mm before 24 weeks + history of loss/surgery. Usually McDonald (transvaginal)
Rescue Cerclage Cervix is dilating WITHOUT active contractions. Emergency transvaginal
Transabdominal Failed vaginal cerclage or extensive cervical surgery. Via Laparotomy. Must deliver by CS.
5. Epidural vs. General Anesthesia
Feature Epidural Anesthesia General Anesthesia (GA)
Usage First choice for labor pain & >85% of emergency CS Used only for strict emergencies or Epidural contraindications
Maternal Mortality Risk Very Low Highest direct anesthetic-related mortality
Absolute Contraindications Coagulopathy (low platelets), Sepsis, Hypovolemia Rarely absolute, but high risk in severe obesity/airway issues
Major Complication Accidental Total Spinal Anesthesia Aspiration pneumonitis (Mendelson's syndrome)