Transcutaneous Electrical Nerve Stimulation for Pain Control During First-trimester Abortion

First-trimester abortion aspiration procedures are painful and sedation is typically provided. It is unsafe to drive after sedation due to the prolonged motor delay from some anesthetic agents. Without a known escort, most clinics do not allow patients to use public transportation, taxis, or rideshare services. Arranging a ride may be harder for those seeking abortion care than other surgical procedures given privacy concerns and the need to travel far distances. Additionally, some people have medical reasons that makes sedation in an outpatient abortion clinic unsafe. As abortion restrictions increase and more people need to travel far distances to access care, it is important to investigate non-pharmacologic pain control options.

Transcutaneous electrical nerve stimulation (TENS) delivers a low-level electrical current through the skin. By activating the descending inhibitory systems in the central nervous system, these pulses of electrical current reduce sensitivity to pain. TENS has been shown to be effective in decreasing pain with menstrual cramps and during medication abortion, and it was found to be non-inferior to IV sedation for first-trimester procedural abortion. However, it remains unclear if TENS is better than ibuprofen and local anesthesia via paracervical block alone.

The overarching goal of this research is to identify an inexpensive, non-pharmacologic, alternative pain control strategy for those with a medical or social contraindication to IV sedation. The specific aim of this project is to evaluate the efficacy of TENS to prevent pain during first-trimester procedural abortion. To achieve this objective, a blinded, randomized superiority trial comparing the use of TENS to sham for management of pain during first-trimester aspiration abortion is proposed. This research is significant because the validation of a non-pharmacologic pain management technique would decrease barriers to accessing abortion care.

Abortion is common: one in four individuals will seek this care during their reproductive lifetime. Most abortions occur in the first trimester and nearly all - greater than 95% - occur in the outpatient clinic setting. Uterine aspiration is painful; most patients desire additional analgesia beyond local anesthesia. However, not every patient is a candidate for office sedation since multiple medical conditions are a contraindication and patients must have a ride home. The prolonged motor delay from some anesthetic agents makes driving after sedation unsafe. Without a known escort to monitor for surgical and anesthetic complications as recommended by the American Society of Anesthesia, most clinics do not allow patients to use public transportation, taxis, or rideshare services. Arranging a ride may be harder for those seeking abortion care than other surgical procedures given privacy concerns and the need to travel far distances. As abortion restrictions increase and more people need to travel far distances to access care, it is important to investigate non-pharmacologic pain control options. Transcutaneous electrical nerve stimulation (TENS) delivers an electrical current through the skin to activate the descending inhibitory systems in the central nervous system, effectively reducing sensitivity to pain. A previous trial comparing TENS to IV sedation found similar postoperative pain scores with a significantly shorter recovery time in the TENS group; however, this study did not evaluate or report intraoperative pain scores. It was found in a randomized controlled trial comparing TENS to IV sedation (in conjunction with local anesthesia) for first-trimester surgical abortion and that TENS had non-inferior pain scores to IV sedation and was considered an acceptable modality for pain control among participants. Through this proposed double blinded randomized controlled trial, it is hoped to demonstrate that TENS is a superior, non-invasive alternative pain control option for people undergoing surgical abortion in the first trimester who otherwise are not eligible for or decline IV sedation. Ultimately, the hope is to identify an inexpensive, alternative, non-pharmacologic pain control strategy for those with a medical or social contraindication to IV sedation in an effort to decrease barriers to accessing abortion care.

Eligibility Criteria:
Inclusion Criteria:

* 18 years old or older
* English- or Spanish-fluency
* \<12 weeks gestation
* Presenting for aspiration abortion

Exclusion Criteria:

* Planned use of oral or IV sedation
* Contraindications to office-based procedure as determined by attending physician
* Fetal demise
* Requiring pre-procedure use of misoprostol
* Contraindication to TENS units use (pacemaker or epilepsy)