Transcutaneous Electrical Nerve Stimulation (TENS) for IUD Insertion Pain

Inclusion Criteria: In order to participate in the study, an individual must meet all the following criteria: * Presenting for IUD initiation during ambulatory care visits to the Mount Sinai Complex Family Planning service * Provision of signed and dated informed consent form for IUD Insertion * English speaking and age 18 or older * Opting for either LNG 52mg or copper T380A IUD * Stated willingness to comply with all study procedures Exclusion Criteria: * Contraindication to IUD initiation (i.e. pregnancy, current pelvic infection, distorted uterine anatomy) * Contraindication or allergy to ibuprofen * History of a chronic pain disorder * Recent opioid use in the previous 30 days * History of a cardiac arrhythmia * History of heart disease (i.e. atrial fibrillation, congestive heart failure) * Presence of an implantable device with an electrical discharge (i.e. pacemaker) * BMI \> 50 (class IV obesity) * History of TENS use * Planned pain intervention outside standard of care (i.e. paracervical block) OR pre-procedure use of non-standard pain medication (i.e. benzodiazepines, muscle relaxers, gabapentin, benadryl) * History of epilepsy