Background: A caesarean section (CS) can cause a defect or disruption of the myometrium at the site of the uterine scar, called a niche. In recent years, an association between a niche and postmenstrual spotting after a CS has been demonstrated. Hysteroscopic resection of these niches is thought to reduce spotting and menstrual pain. However, there are no randomised trials assessing the effectiveness of a hysteroscopic niche resection. Methods/Design: We planned a multicentre randomised trial comparing hysteroscopic niche resection to no intervention. We study women with postmenstrual spotting after a CS and a niche with a residual myometrium of at least 3 mm during sonohysterography. After informed consent is obtained, eligible women will be randomly allocated to hysteroscopic resection of the niche or expectant management for 6 months. Discussion: This trial will provide insight in the (cost)effectiveness of hysteroscopic resection of a niche versus expectant management in women who have postmenstrual spotting and a niche with sufficient residual myometrium to perform a hysteroscopic niche resection. Trial registration: Dutch Trial Register NTR3269. Registered 1 February 2012. ZonMw Grant number 80-82305-97-12030

Abnormal uterine bleeding, Caesarean section, Hysteroscopic resection, Niche, Postmenstrual spotting, Scar defect,
BMC Women's Health
Franciscus Gasthuis & Vlietland

Vervoort, A.J.M.W, Van der Voet, L.F, Witmer, M, Thurkow, A.L, Radder, C.M, van Kesteren, P.J.M, … Huirne, J.A.F. (2015). The HysNiche trial: Hysteroscopic resection of uterine caesarean scar defect (niche) in patients with abnormal bleeding, a randomised controlled trial. BMC Women's Health, 15(1). doi:10.1186/s12905-015-0260-8