Feasibility study on uterine contractility across the menstrual cycle using electrohysterography

Historically, female health has been overlooked for a long time. Initially dismissed due to religious constraints and popular myths, it only began to receive attention in medical research to better understand pregnancy and labor, reflecting the perception of the woman’s body at the time. This narrow focus on the uterus as merely a gestational organ persisted until the 21st century, when the presence of a significant gap in the understanding of the non-pregnant and pathological uterus was finally acknowledged. And, although recent decades have seen growing efforts to address this gap, much remains to be explored. To this day, routine gynecological care lacks suitable, non-invasive diagnostic tools capable of monitoring uterine health outside pregnancy, verifying fertility, and promptly diagnosing debilitating conditions such as endometriosis or adenomyosis. The clinical methods currently used, such as intrauterine pressure catheters or transvaginal ultrasound, are invasive, uncomfortable, and heavily reliant on operator expertise. An interesting possibility to address this unmet need is electrohysterography (EHG), a non-invasive method that records uterine electrical activity through electrodes placed on the abdomen. While well established for monitoring contractility during pregnancy, its application in non-pregnant individuals has been largely overlooked. Yet, it holds great potential as a safe, reproducible, and operator-independent tool for assessing uterine function. Importantly, EHG signals capture both fast-wave (FW) and slow-wave (SW) activity, which reflect the underlying electrophysiological mechanisms of contractility. Although extensively investigated in pregnancy, their characterization outside gestation remains almost unexplored, particularly for SW, which has not yet been studied in humans. This thesis investigates the feasibility of applying EHG to monitor uterine activity throughout the menstrual cycle in non-pregnant women. By acquiring and analyzing FW and SW signals in the different phases of the cycle, the study aims to evaluate whether EHG can detect different contractile activity patterns depending on the specific cycle phase. A specific acquisition protocol was developed, and a combination of signal pre-processing and feature extraction techniques was used to assess the presence and variability of uterine contractions across the menstrual cycle, in both fast and slow contractions. Overall, this work lays the groundwork for a broader use of EHG in reproductive health. If proven feasible, future developments could include improved menstrual cycle monitoring, non-invasive fertility assessment, and support for the early detection of gynecological conditions, contributing to more personalized and accessible care for women.