Hysteroscopic resection of uterine scar defects (niche) in patients with abnormal bleeding, a randomised controlled trial

In western countries, caesarean rates are rising. A caesarean section can cause
a niche (defect at the site of the uterine scar); the incidence of niche
related postmenstrual spotting in the Netherlands is expected to be 60 %.
Promising results are reported after an innovative minimally invasive
hysteroscopic resection of these niches. However its (cost) effectiveness in
comparison to a control group has to be proven.

Our primary objective is to study the effectiveness of hysteroscopic resection
for niche related uterine bleeding disorders. The procedure will be performed
in small niches with a residual myometrium of more than 3mm.
Our secondary objective is to asses the quality of life, sexual function and a
cost-effective analysis will be made

The study is a multicentre randomized controlled trial. After the patiente has
received the information letter and signed the informed consent she will be
included and randomised. Patients will be randomly allocated to hysteroscopic
resection or expectant management. Randomization will be performed centrally
with the use of a permuted block design, stratified for recruiting centre.
After randomization the patients who undergo the intervention will be assessed
by an anesthesiologist.

The patients allocated for hysteroscopic niche resection will undergo the
procedure under spinal or general anaesthesia in lithotomic position. An
experienced gynaecologist will asses the niche and the intra-uterine cavity
according to standardized criteria. Resection will be performed using a 9mm
resectoscope on a standardize way. In case of bipolar currency, 0,9 % NaCL and
in case of monopolar, Sorbitol fluid will be used to induce distension of the
uterine cavity. The distal part of the niche in utero is resected and the niche
surface will be superficially coagulated under abdominal ultrasound guidance to
assure sufficient distance to the bladder wall during resection. Possible
polyps in the niche will be resected.

Patients will be informed about the procedure and will be told that there is no
evidence about the effectiveness of the therapy. The procedure will be in a
research setting. The complications with a hysteroscopy will be told, i.e.
bleeding, infection, perforation of the uterus or bladder, or adhesions in the
uterine cavity post-operatively. In rare cases a defect of the bladder can
occur, caused by coagulation of the surface of the niche. Therefore the
procedure is not performed if the residual myometrium is less than 3mm. In a
previous pilotstudy of 20 patients no complications occurred.
Also in every patient one specimen of blood will be collected for analysis of
AMH ( marker of ovarian reserve capacity) in the future.