Incidence of Pruritus Using Intrathecal Fentanyl Versus Epidural Fentanyl to Initiate Labour Analgesia.

Inclusion Criteria: * Age ≥ 18 years * Vaginal delivery * Gestational age ≥ 37 weeks * Requesting neuraxial analgesia * French or English language Exclusion Criteria: * ASA score \> 3 * Allergy or contraindication to receiving opioids/local anesthesia (morphine or fentanyl) * BMI \> 40 kg/m² * Hepatic or renal failure, * Severe preeclampsia and signs of severity according to the criteria of the American College of Obstetricians and Gynecologists * Maternal hemorrhage (placental abruption, hepatic subcapsular hematoma,...) * Severe scoliosis * Biliary cholestasis or polymorphic eruption of pregnancy * Inability to provide informed consent, either secondary to mental or physical disability or a significant language barrier (inability to understand English or French) * Prior administration of an opioid or opioid misuse