TENS for Postpartum Uterine Pain During Breastfeeding

This randomized, controlled, parallel-group clinical trial will evaluate the efficacy and safety of Transcutaneous Electrical Nerve Stimulation (TENS) as a non-pharmacological intervention for reducing oxytocin-induced postpartum uterine contractions during breastfeeding. The study cohort consists of 124 eligible multiparous women (2 or more previous births) admitted to the Department of Obstetrics and Gynecology at Holy Family Hospital in Nazareth, Israel, within 48 hours following a term, singleton, vaginal delivery. Following the acquisition of written informed consent, participants will be randomized at a 1:1 ratio into either the TENS study group or the standard care control group. The experimental protocol will be integrated into two consecutive breastfeeding sessions. Body positioning will be strictly standardized across both cohorts. TENS Study Group (Intervention): Prior to the second consecutive breastfeeding session, four conductive gel electrodes will be affixed to the participant. Two electrodes will be positioned bilaterally over the lower abdomen, directly overlying the uterus. The remaining two electrodes will be placed in parallel in the S2-S4 dermatomal region to target the spinal nerve pathways receiving nociceptive afferent input from the uterus and cervix. Active stimulation will commence a few minutes prior to breastfeeding and continue for the entire duration of the feed. The TENS device will deliver a 100-Hz current and 75 msec pulse for 40 min, using 20-60 milliamps of intensity.

To establish a baseline pain score, the first evaluated breastfeeding session for this group will be conducted without TENS application, followed by active TENS during the second session. Control Group Protocol: Participants assigned to the control group will receive standard postpartum care and will undergo the identical data collection schedule across two consecutive breastfeeding sessions, but without any TENS electrode placement or electrical stimulation.

For both study arms, pharmacological analgesia will remain accessible as needed per existing institutional department protocols, and all instances of medication administration (including specific agent, timing, and dosage) will be precisely documented. Uterine pain scores will be captured across both groups at three identical time points during each of the two consecutive breastfeeding sessions: Maternal discomfort associated directly with the physical application or sensation of the TENS unit will be separately quantified.

Inclusion criteria

• Maternal Age above 18
• Term delivery (37 weeks or more)
• Vaginal delivery within the past 48 hours.
• Multiparous women (2 or more previous births)
• Delivery of a singleton
• Have the well to breastfeed

Exclusion criteria

• Contraindication to TENS (pacemaker, epilepsy, active infection, uncontrolled hyper / hypotension.)
• Chronic analgesia use
• Severe complications requiring intervention (severe PPH) or intensive care
• Skin lesions, infections, or scars at proposed electrode sites
• Neonatal intensive care unit admission