Obstetrics The Peer Teaching Society is not liable for false or misleading information…

Areas you need to cover … Booking appointments, screening for congenital abnormalities etc Physiology of labour Pre-eclampsia Diabetes in pregnancy APH Haemolytic disease of the newborn Obstetric emergencies PROM PPH Abnormal fetal growth Infections in pregnancy Preterm labour: causes and prevention Teratogenic drugs The Peer Teaching Society is not liable for false or misleading information…

Physiology of labour Painful uterine contractions accompany dilation and effacement of the cervix 37 – 42 weeks gestation First stage: initiation to full cervical dilatation Second stage: full dilatation to delivery of fetus Third stage: delivery of fetus to placental delivery The Peer Teaching Society is not liable for false or misleading information…

Physiology of labour… Mechanical factors of labour Powers Passage Uterine contractions causing effacement and dilatation of cervix Passage Bony pelvis and soft tissues Passenger Attitude – degree of flexion of head on the neck. Ideal = vertex presentation (maximal flexion) Rotation Size Problem with any  failure to progress  assisted delivery The Peer Teaching Society is not liable for false or misleading information…

The Peer Teaching Society is not liable for false or misleading information…

First stage The cervix opens to ‘full dilatation’ to allow the head to pass through Latent phase: <3cm Active phase: 3 - 10cm Head descends in a flexed position, starts to rotate and ROM The Peer Teaching Society is not liable for false or misleading information…

Second stage Full dilatation to delivery of the fetus Passive stage: full dilatation until head reaches pelvic floor and woman feels desire to push Active stage: pushing! Average 20 mins multiparous. 40 mins nulliparous The Peer Teaching Society is not liable for false or misleading information…

Third stage From delivery of the fetus to complete delivery of placenta Average 15 mins with 500ml blood loss The Peer Teaching Society is not liable for false or misleading information…

Pre-eclampsia BP >140/90mmHg with proteinuria > 0.3g/24 hours Risk factors: nulliparity, PMH, FH, long period between pregnancies, extremes of maternal age (>40yrs), pre-existing CKD, HTN, DM, large placenta (twins, fetal hydrops), obesity Px: usually asymptomatic. Signs: HTN, oedema, epigastric tenderness The Peer Teaching Society is not liable for false or misleading information…

Pre-eclampsia cont. Ix: Urine dipstick for protein Protein creatinine ratio >30mg/nmol 24 hour urinary collection >0.3g protein The Peer Teaching Society is not liable for false or misleading information…

Pre-eclampsia complications Maternal Eclampsia (seizures) CVA (haemorrhagic) Clotting problems – DIC Organ problems – liver failure, renal failure, pulmonary oedema HELLP Haemolysis Elevated Liver enzymes Low Platelets Fetal IUGR Preterm birth, hypoxia, placental abruption The Peer Teaching Society is not liable for false or misleading information…

Pre-eclampsia management Only cured by delivery! Admit if symptomatic, proteinuria, BP >160/110, ? fetal compromise Antihypertensives – labetalol (or nifedipine or hydralazine) Magnesium sulphate in eclampsia (+ IV labetalol or hydralazine) Steroids if preterm delivery required Mild: deliver by 37 weeks Complications or fetal distress: deliver at any gestation The Peer Teaching Society is not liable for false or misleading information…

Antepartum haemorrhage Bleeding from the genital tract after 24 weeks gestation Causes Common: undetermined, placental abruption, placenta praevia Rarer: incidental genital tract pathology, uterine rupture, vasa praevia The Peer Teaching Society is not liable for false or misleading information…

Placenta praevia Placenta implanted in uterine lower segment Complications: haemorrhage, obstructs head engagement (requires c- section), placenta acreta, placenta percreta Px: intermittent painless bleeds increasing in frequency and intensity Ix: USS, FBC and crossmatch if bleeding Tx: C-section at 39 weeks, or earlier if heavy bleeding. The Peer Teaching Society is not liable for false or misleading information…

Placental abruption Separation of part/all of placenta before delivery (>24 weeks) Causes: idiopathic, IUGR, pre-eclampsia, autoimmune disease, smoking, PMH, HTN Px: painful bleeding …. but MAY NOT BLEED – blood may track between membranes and myometrium, enter liquor etc. O/E: tachycardia, uterine tenderness, contractions, ‘woody uterus’, maternal collapse, abnormal fetal heart beat, hypotension (late) The Peer Teaching Society is not liable for false or misleading information…

Placental abruption cont. Ix: diagnosis is clinical. USS excludes placenta praevia. CTG for fetus, FBC and clotting for mother. Complications: fetal death, massive haemorrhage, DIC, renal failure, maternal death Tx: Admit if suspected even without bleeding. Resuscitate if required (blood), deliver by c-section if fetal distress/death/ > 37 weeks The Peer Teaching Society is not liable for false or misleading information…

Vasa praevia Fetal blood vessels running in the membranes in front of the presenting part. When membranes rupture vessels may rupture with massive fetal bleeding. Px: Moderate, painless bleeding at ROM. Severe fetal distress. Tx: C-section often not fast enough to save the fetus. The Peer Teaching Society is not liable for false or misleading information…

Obstetric emergencies Shoulder dystocia Uterine rupture Amniotic fluid embolism The Peer Teaching Society is not liable for false or misleading information…

Shoulder dystocia Normal downward traction fails to deliver shoulders after head. Requires urgent additional manoeuvres. Risk factors: macrosomia, PH, maternal obesity, maternal DM, short maternal height, instrumental delivery Tx: McRoberts manoeuvre and suprapubic pressure, Wood’s screw manoeuvre Complications: Erb’s palsy, fetal death High cause of medical negligence claims!!! The Peer Teaching Society is not liable for false or misleading information…

Cord prolapse Umbilical cord descends below presenting part after rupture of membranes Spasm/compression of cord causes fetal hypoxia Risk factors: preterm labour, breach presentation, polyhydramnios, abnormal lie, twin pregnancy Px: Fetal distress and palpable cord vaginally Tx: Prevent compression of cord by presenting part (tocolytics e.g. turbutaline/nifedipine, or manually). Immediate c-section or instrumental delivery may be appropriate The Peer Teaching Society is not liable for false or misleading information…

Amniotic fluid embolism Liquor enters maternal circulation causing anaphylaxis, seizures, cardiac arrest Causes DIC, pulmonary oedema, ARDS, rapid death. Risk factors: strong contractions, polyhydramnios Tx: Diagnosis usually at post-mortem!! Resuscitation and supportive treatment in ICU setting The Peer Teaching Society is not liable for false or misleading information…

Uterine rupture Spontaneous tear of uterus. Bleeding from rupture site, acute fetal hypoxia and massive internal maternal haemorrhage. Risk factors: scarred uterus, previous c-section, neglected obstructed labour, congenital uterine abnormalities Tx: resuscitation, urgent laparotomy for fetal delivery, repair/remove uterus The Peer Teaching Society is not liable for false or misleading information…

Post partum haemorrhage Loss of >500ml blood <24 hours after delivery (or >1000ml after c- section) Causes: Retained placental fragments, atonic uterus, perineal trauma, uterine rupture, cervical tear, high vaginal tear Prevention: routine use of oxytocin in third stage of labour Tx: Resuscitation, manual removal of retained placenta, identify and treat cause Persistent haemorrhage requires surgery. Hysterectomy may be required. The Peer Teaching Society is not liable for false or misleading information…

Infections in Pregnancy HSV HBV Rubella HIV Toxoplasmosis HZV CMV Syphilis Parvovirus Group B Streptococcus The Peer Teaching Society is not liable for false or misleading information…

Teratogenic drugs Warfarin ACE inhibitors Anti-thyroid drugs: Carbimazole (recommended for 2nd and 3rd trimester – block and replace regimen contraindicated), propylthiouracil (recommended for pre-pregnancy and 1st trimester) Angiotensin II antagonists Antiepileptics (minus lamotrigine) Methotrexate Antibiotics (trimethoprim, tetracycline, doxycycline) Isotretinoin Alcohol, cocaine, high dose vitamin The Peer Teaching Society is not liable for false or misleading information…

Name 1 additional test for diagnosis? A patient has high blood pressure, feeling puffy, flashing lights and a headache. Name 1 additional test for diagnosis? 4 further clinical and laboratory investigations to assess severity of preeclampsia? 5 complications to prevent or exclude in this patient? The Peer Teaching Society is not liable for false or misleading information…