Inclusion Criteria:  Written informed consent 18-45 years old American Society of Anesthesiologists (ASA) physical status 1-2 Undergoing oocyte retrieval procedures Planned number of oocytes to be retrieved <15  Exclusion Criteria:  Known allergy to fentanyl, acetaminophen, dipyrone, lidocaine, propofol or NSAIDs. Endometriosis Diagnosis of chronic pain Opioid dependency, defined by consumption of oral morphine equivalent of greater than or equal to 60mg a day for 7 days or longer, for any time period. Weight < 50 kg Cannabis use Major psychiatric disorder - Schizophrenia, bipolar disorder, major depression. Epilepsy disorder under anti-convulsant therapy. Renal insufficiency, defined as creatinine clearance <60 ml/hr Hepatic disease