Transcutaneous Electrical Nerve Stimulation (TENS) units offer a non-pharmacological approach to pain management during labor. This article aims to guide readers on the effective and safe use of a TENS unit for labor, with a focus on proper pad placement.
Understanding TENS for Labor
A TENS unit aids in managing labor pain through two primary physiological mechanisms. One mechanism involves the “Gate Control Theory of Pain,” where stimulating non-pain-carrying nerves “closes a gate” in the spinal cord, blocking pain signals from reaching the brain. The electrical impulses from the TENS unit create a tingling or buzzing sensation that the brain registers instead of the pain signals from contractions.
The TENS unit also encourages the body’s natural pain relief system by stimulating the release of endorphins. Endorphins are natural painkillers produced by the body, reducing pain perception.
Key Pad Placements for Labor Pain
Proper placement of the TENS unit pads is central to its effectiveness in managing labor pain. Most TENS units designed for labor typically use four self-adhesive electrode pads. These pads are strategically positioned on the back to target nerve pathways involved in labor pain.
For pain primarily felt in the lower back, often referred to as “back labor,” two pads are commonly placed over the sacral area. This involves positioning them horizontally on either side of the spine, just above the buttocks, specifically over the sacral dimples. This placement targets the S2-S4 dermatomes, which are nerve roots that transmit pain messages from the uterus and cervix during labor.
The other two pads are typically placed higher on the back, around the bra-strap level. These are positioned vertically on either side of the spine, approximately 4cm from the midline. This upper placement can help address pain that might radiate higher up the back during contractions.
Before applying the pads, ensure the skin is clean, dry, and free from oils or lotions to ensure good adhesion and conductivity. The pads should be securely attached to prevent them from moving during labor, which could reduce effectiveness or cause discomfort. For labor, pads are almost exclusively placed on the back to avoid direct stimulation of the uterus.
Practical Application During Labor
Starting TENS unit use in early labor is recommended. This allows the body to gradually build up natural pain-relieving endorphins before contractions intensify. Begin using the TENS unit as soon as regular contractions or backache start.
Once the pads are in place, the intensity settings can be adjusted. You should gradually increase the intensity until a strong but comfortable tingling or buzzing sensation is felt under the electrodes. As labor progresses and contractions become stronger, the intensity can be increased further to maintain the desired level of sensation, as your body may adapt to the initial setting. Many maternity-specific TENS units include a “boost” button, which can be pressed at the onset of a contraction to deliver an extra surge of electrical impulses, providing increased pain relief during the peak of each contraction.
TENS machines typically offer different modes, such as burst or continuous. Burst mode is often used in early labor, while a continuous mode might be preferred as labor advances. The TENS unit is portable, allowing for mobility and changes in position during labor, which can be beneficial for managing pain and promoting labor progression. TENS therapy can be continued for as long as desired, but it should be removed if entering water for a bath or shower.
Important Safety Information
While TENS units are generally safe for labor, certain precautions and contraindications apply. Consult a healthcare provider, such as a doctor or midwife, before use.
Pads should never be placed over the abdomen during pregnancy or labor, particularly not directly over the uterus, to avoid unwanted contractions. Other areas to avoid include the head, neck, eyes, mouth, or directly over the front or sides of the neck. Pads should also not be placed on broken, irritated, or numb skin.
TENS units are not suitable for everyone. Individuals with pacemakers, certain heart conditions, or epilepsy should avoid using TENS, as the electrical impulses can interfere with these conditions. If pain worsens or skin irritation occurs, the TENS unit should be removed immediately. Always follow the manufacturer’s instructions and ensure the unit is purchased from a reputable source.