Abstract: A medical device is disclosed for monitoring and modulating uterine contractions. The medical device may include a uterine pacemaker and an intravaginal electrode carrier, which may both be located within the body. The intravaginal electrode carrier includes sensing and modulating electrodes that measure uterine electroactivity and apply electrical modulation, respectively. The uterine pacemaker receives the measured uterine electroactivity from the intravaginal electrode carrier and generates the electrical modulation applied by the modulating electrodes. The electrical modulation may be used to inhibit or induce uterine contractions. The intravaginal electrode carrier may be used in addition or as an alternative to an external uterine muscle activity monitor (e.g., a tocodynamometer) for a more accurate measure of uterine contractions that is noninvasive.