Transcutaneous electrical nerve stimulation for the relief of post-partum uterine contraction pain during breast-feeding: a randomized clinical trial.

Abstract

To evaluate transcutaneous electrical nerve stimulation (TENS) used to relieve uterine contraction pain during breast-feeding in multiparous women. A controlled and randomized clinical trial was performed with 32 post-partum multiparous women who were breast-feeding. The participants were randomized into an experimental (EG, n = 16) and a control group (CG, n = 16). Pain was assessed using the Numerical Rating Scale and the descriptors of the Present Pain Intensity (PPI - McGill) during two sequential feeds. In the first assessment, the post-partum women in the EG and CG were monitored while breast-feeding and questioned regarding the degree of uterine contraction pain. In the second assessment, which was performed at the next feed, the EG used TENS while the CG was monitored, with pain being reassessed following. In the EG, the TENS electrodes were placed between T10-L1 and S2-S4, with a frequency of 100 Hz, a pulse duration of 75 μs and amplitude adjusted to produce a strong and tolerable sensation for 40 min. A descriptive analysis of the data and comparative intra- and intergroup analyses were performed by means of a non-parametrical test, with a significance level P ≤ 0.05. The level of basal pain was 5.56 in the EG and 5.50 in the CG. In the intragroup analysis, the EG (P < 0.0001) and CG (P = 0.04) presented significant pain reduction. In the intergroup analysis, the EG had significant pain reduction (P < 0.01) in comparison to the CG. In the PPI analysis, a non-significant decrease in pain intensity was observed in the EG. TENS was found to be effective in reducing post-partum uterine contraction pain during breast-feeding.