Complications after 20 weeks

Abruptio placentae

• Premature separation of placenta from uterine lining
• 1% of all pregnancies
• Usually spontaneous but can be traumatic (mostly minor)
• Risk factors
  • HTN
  • Trauma
  • Smoking
  • Advanced maternal age
  • Cocaine abuse
  • Black race
  • Previous uterine surgery incl. Caesarean
  • Previous abruptio placentae

• Complete, partial or concealed
• Clinical diagnosis as USS not sensitive enough
• Presentation
  • Painful vaginal bleeding
  • Woody abdominal examination
  • Severe uterine pain or tenderness
  • Uterine hypertonicity
  • Hypotension
  • Nausea, vomiting
  • Back pain (could be the only symptom)
  • Symptoms can be subtle so need HIGH INDEX OF SUSPICION

• Complications
  • Haemorrhagic shock
  • DIC (more likely if severe abruption leading to fetal demise)
    • Fibrinogen <3 suggests severe consumptive coagulopathy
  • Uterine rupture
  • Multiple organ failure
  • Foetal neurodevelopmental abnormalities 
  • Foetal death
    • Usual if >50% separation

Treatment

• 2x large IV cannulae
• FBC, G&H&Antibodies, Chem20, Coags
• Fluid resuscitation incl. blood products as required
• USS
  • Specific but NOT SENSITIVE
  • Lacks sensitivity for retroplacental clot
  • Useful as adjunct to rule out alternative causes of vaginal bleeding
• Operative intervention + Delivery

Placenta praevia

• Placenta that extends near, partially over or beyond the internal cervical os
• Presentation
  • Painless bright red vaginal bleeding
  • Sentinel bleed usually self-resolves only to recur
  • Uterine irritability can obscure diagnosis (20%)
  • TAUSS is 95% sensitive and TVUSS even better (AND PROVEN SAFETY)
• Digital or speculum exam may precipitate fatal bleeding
• Needs examination in theatre with double setup
• USS can show location of placenta
• Same Rx as abruptio placentae

Vasa previa

• 1/2500 births
• Velamentous insertion of umbilical cord in to lower uterine segment such that cord traverses fetal membranes before it inserts into placenta
• Risk factors
  • Placenta praevia
  • IVF
  • Bi-lobed placenta
• Haemorrhage usually occurs with SROM
• As labour begins and fetus descends, vessel rupture can lead to fetal exsanguination
• Perinatal mortality 30-100%
• Immediate C-section necessary

Preterm birth

• Leading cause of infant morbidity and mortality
• 13% of pregnancies
• Aetiology
  • Spontaneous
  • Secondary to PROM
  • Intentionally induced
• Preterm labour defined as <37 weeks

Risk factors

• Maternal
  • Age of mother <18 or >35
  • African (inc. 60%), Asian (incr. 40%), ATSI (incr. 70%)
  • Smoker (incr. 30%)
  • Psychosocial stress
  • Low SES
  • High or low BMI

• Medical and pregnancy
  • Short cervical length
  • Previous preterm birth
  • Bacterial vaginosis (double risk)
  • UTI
  • Vaginal bleeding
  • Assisted reproduction (twice risk)
  • PPROM
  • Cervical surgical procedures
  • Uterine anomalies
  • Multiple gestation

Modifiable risk factor reduction

• Treat bacterial vaginosis, asymptomatic bacteriuria and GBS
• Progesterone therapy
• Cervical cerclage

Premature rupture of membranes

• Definition:
  • Rupture of membranes prior to labour
• PROM <37 weeks gestation = Preterm premature ROM (PPROM)
  • Causes 1/3 of all preterm deliveries
  • Majority of women give birth within 1 week
• AVOID DIGITAL VAGINAL EXAMINATION as increases morbidity/mortality and decreases the latent period

• History
  • Gush of fluid, contractions, LNMP, bleeding, recent intercourse, recent infections, fever, history of GBS
• Examination
  • Fundal height, fetal HR, sterile speculum exam for cervical dilatation/effacement, pooling of fluid in vagina (can apply fundal pressure or get patient to cough to elicit fluid leakage)
  • Sterile digital exam for cervical dilatation (unless ROM/placenta praevia)
• Labs
  • Vaginal fluid: Glass slide ferning, foetal fibronectin testing
  • Low vaginal/perianal swab for GBS
  • High vaginal swabs for Chlamydia, Neisseria and bacterial vaginosis
  • Urine MCS
• Foetal surveillance with CTG

Treatment

• Corticosteroids
  • <35+0 weeks gestation, speeds fetal lung maturity and decreases risk of intraventricular haemorrhage and necrotising enterocolitis. No increase in maternal or fetal infection rates.
  • Betamethasone 11.4mg IM then 2nd dose 24 hours later (12 hours later if high risk of preterm birth)
• Antibiotics
  • Decreases neonatal infection, prolongs latency period, reduces post-partum endometritis/chorioamnionitis, neonatal sepsis, neonatal pneumonia and intraventricular haemorrhage
  • If established labour give intrapartum GBS prophylaxis irrespective of GBS or membrane status
  • Ampicillin, Gent and Metronidazole for chorioamnionitis

• Tocolytics
  • Not been shown to prevent preterm birth or reduce morbidity related to gestational age
  • May prolong latency and allow time for corticosteroid and antibiotic administration +- transfer of patient
  • Indicated if 24-36 weeks gestation in preterm labour
  • Nifedipine 20mg q30min until contractions ceased then 20mg q6h PO
• Magnesium sulphate for neuroprotection
  • 24-30 weeks gestation for established labour or imminent birth
  • 4g IV over 20 minutes then 1g/hr for 24 hours (same as pre-eclampsia dose)
• Expeditious delivery
  • Recommended if >34 weeks with pPROM to avoid infection complications
  • Any attempt at prolonging latency period >34 weeks has not resulted in decreased perinatal complications

GBS

• If febrile/unwell on arrival – Amp/Gent/Metronidazole for chorioamnionitis
• If term PROM
  • Antibiotics if maternal risk factors NOT to prolong latency
    • Commence after onset of labour (aiming for at least 4 hours from birth)
    • BenPen 3g IV then 1.8g q4h until birth
    • Maternal risk factors
      • GBS colonisation in current pregnancy
      • GBS bacteriuria in current pregnancy
      • Previous baby with EOGBSD
      • ROM >18 hours
      • Temp >38

• If preterm PROM
  • Culture for GBS
  • If imminent labour give BenPen as above
  • If no labour – Erythromycin 250mg QID PO

Post-partum haemorrhage (PPH)

• Most common cause of maternal mortality worldwide and top 3 in developed nations (behind VTE and HTN)
• Mortality rate 1.4/100 000 live births
• Excessive bleeding defined as:
  • >10% drop in Hct
  • Need for PRBC transfusion
  • Volume loss that causes symptoms of hypovolaemia
• Primary PPH = Within 24 hour of delivery
• Secondary PPH = 24 hrs to 6 weeks post-partum

• Causes (4T’s)
  • Tone
  • Tissue
  • Trauma incl. uterine rupture/inversion
  • Thrombin – Coagulopathy

• Physiological changes in pregnancy can mask signs of haemorrhage
  • Plasma volume increased 40%
  • Red blood cell volume increased 25%
  • HR increased up to 110
  • Reduced BP (may need 30% blood volume loss before this drops)

• Resuscitate
  • IV access, crystalloid and blood products
  • Keep warm
  • Correct severe acidosis, iCa <1.1 and fibriogen < 2.5
• Placenta out and complete?
  • If retained, do not massage fundus
  • Give 3rd stage oxytocic
  • Apply continuous cord traction

• Fundus firm?
  • Massage fundus, ensure 3rd stage oxytocic, expel uterine clots, IDC to ensure bladder empty
  • Oxytocin 5U IV over 1-2 minutes
  • Ergometrine 250mcg IV/IM
  • Oxytocin infusion 5-10U/hr
  • PFG2alpha 0.5-1mg intramyometrial
• Genital tract trauma?
  • Inspect
  • Clamp bleeders and repair if able
• Blood clotting?
• If bleeding not controlled – bimanual compression and OT

Uterine rupture

• Rare complication in unscarred uterus (0.01%)
• Risk factors
  • Previous C-section (0.2-0.8%) = 10x higher risk than unscarred
  • Malpresentation
  • Labor dystocia
  • Hypertensive disorders of pregnancy
  • Bicornuate uterus
  • Grand multiparity
  • Connective tissue disorders
  • Abnormal placentation
  • Induction  and augmentation of labour

• Presentation
  • Persistent abdominal pain
  • Vaginal bleeding
  • Loss of fetal station
  • Palpable uterine defect
  • Fetal distress and bradycardia

• Treatment
  • Resuscitation
  • Blood products
  • Emergency delivery of foetus
  • Operative abdominal hysterectomy in most cases

Amniotic fluid embolus

• Amniotic fluid, hair or other debris enter maternal circulation
• Presentation
  • Respiratory distress
  • Pulmonary oedema
  • Hypoxia
  • Altered mental status
  • Seizures
  • Sudden maternal cardiovascular collapse
  • DIC
  • Maternal death
  • Fetal distress

• 60-80% mortality
• 85% of survivors have neurological sequelae
• Risk factors
  • C-section
  • Advanced maternal age
  • Multiparity
  • Abnormal placental implantation
  • Uterine rupture
  • Eclampsia

• Rx
  • Support mother
  • Place in left lateral decubitus position to avoid further IVC compression
  • 100% O2
  • Immediate delivery including perimortem C-section

Peripartum cardiomyopathy

• Dilated cardiomyopathy at any stage of gestation
• Usually in last month of gestation or within 5 months after delivery
• Unknown cause
• Treat as for CCF

Postpartum endometritis

• Any post-partum female who presents with fever should be assumed to have this until proven otherwise
• Pathogens
  • Gram-positive and negative aerobes incl. MRSA/Strep/E. coli
  • Anaerobes
  • Mycoplasma hominis
  • Chalmydia
  • Neisseria
  • Gardnerella vaginalis
  • Most infections polymicrobial

• Presentation
  • Fever
  • Foul smelling lochia
  • Leukocytosis
  • Tachycardia
  • Uterine tenderness
  • Scant discharge may be present, esp. if Group B strep

• Risk factors
  • C-section
  • Multiple gestation
  • Younger maternal age
  • Long duration of labour and PROM
  • Internal foetal monitoring
  • Low SES
  • Digital exam after 37 weeks gestation
  • Maternal HIV

• Treatment
  • Oral antibiotics e.g. clindamycin or doxycycline (unless breastfeeding) if clinically well and not a C-section
  • If unwell or C-section, get IV therapy
• Complications
  • Parametrial phlegmons
  • Abscess formation
  • Infected haematomas
  • Septic pelvic thrombophlebitis
  • Necrotising fasciitis
  • Peritonitis

Last Updated on October 6, 2021 by Andrew Crofton