Mm. Ijland et al., SUBENDOMETRIAL CONTRACTIONS IN THE NONPREGNANT UTERUS - AN ULTRASOUNDSTUDY, European journal of obstetrics, gynecology, and reproductive biology, 70(1), 1996, pp. 23-24
Endometrial wavelike activity was studied by ultrasound, throughout 19
ovulatory cycles in 16 healthy female volunteers. Analysis was focuse
d on the presence of endometrial activity and the wave types. Five act
ivity patterns were distinguished, which varied throughout the cycle.
Endometrial activity was most striking during the periovulatory phase.