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. 2018 Dec 29;18(1):511.
doi: 10.1186/s12884-018-2160-z.

Does endometrial scratching increase the rate of spontaneous conception in couples with unexplained infertility and a good prognosis (Hunault > 30%)? Study protocol of the SCRaTCH-OFO trial: a randomized controlled trial

B N Bui  1 , H L Torrance  2 , C Janssen  3 , B Cohlen  4 , J P de Bruin  5 , J E den Hartog  6 , P J Q van der Linden  7 , K L Deurloo  8 , J W M Maas  9 , R van Oppenraaij  10 , A Cantineau  11 , C B Lambalk  12 , H Visser  13 , E Brinkhuis  14 , J van Disseldorp  15 , B C Schoot  16 , C Lardenoije  17 , M van Wely  18 , M J C Eijkemans  2 , F J M Broekmans  2
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Does endometrial scratching increase the rate of spontaneous conception in couples with unexplained infertility and a good prognosis (Hunault > 30%)? Study protocol of the SCRaTCH-OFO trial: a randomized controlled trial

B N Bui et al. BMC Pregnancy Childbirth. .

Abstract

Background: In the Netherlands, couples with unexplained infertility and a good prognosis to conceive spontaneously (i.e. Hunault > 30%) are advised to perform timed intercourse for at least another 6 months. If couples fail to conceive within this period, they will usually start assisted reproductive technology (ART). However, treatment of unexplained infertility by ART is empirical and can involve significant burdens. Intentional endometrial injury, also called 'endometrial scratching', has been proposed to positively affect the chance of embryo implantation in patients undergoing in vitro fertilization (IVF). It might also be beneficial for couples with unexplained infertility as defective endometrial receptivity may play a role in these women. The primary aim of this study is to determine whether endometrial scratching increases live birth rates in women with unexplained infertility.

Method: A multicentre randomized controlled trial will be conducted in Dutch academic and non-academic hospitals starting from November 2017. A total of 792 women with unexplained infertility and a good prognosis for spontaneous conception < 12 months (Hunault > 30%) will be included, of whom half will undergo endometrial scratching in the luteal phase of the natural cycle. The women in the control group will not undergo endometrial scratching. According to Dutch guidelines, both groups will subsequently perform timed intercourse for at least 6 months. The primary endpoint is cumulative live birth rate. Secondary endpoints are clinical and ongoing pregnancy rate; miscarriage rate; biochemical pregnancy loss; multiple pregnancy rate; time to pregnancy; progression to intrauterine insemination (IUI) or IVF; pregnancy complications; complications of endometrial scratching; costs and endometrial tissue parameters associated with reproductive success or failure. The follow-up duration is 12 months.

Discussion: Several small studies show a possible beneficial effect of endometrial scratching in women with unexplained infertility trying to conceive naturally or through IUI. However, the quality of this evidence is very low, making it unclear whether these women will truly benefit from this procedure. The SCRaTCH-OFO trial aims to investigate the effect of endometrial scratching on live birth rate in women with unexplained infertility and a good prognosis for spontaneous conception < 12 months.

Trial registration: NTR6687 , registered August 31st, 2017.

Protocol version: Version 2.6, November 14th, 2018.

Keywords: Endometrial injury; Endometrial receptivity; Endometrial scratch; Endometrial scratching; Expectant management; Hunault > 30%; Implantation failure; Unexplained infertility.

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Conflict of interest statement

Authors’ information

Additional author’s information is not relevant to the interpretation or understanding of this article.

Ethics approval and consent to participate

Ethical approval of the Medical Ethics Committee of the UMC Utrecht has been obtained for this study under registration number 17–592/D, date of approval 28 September 2017. This study is registered in the Dutch trial registry (www.trialregister.nl) from 31 August 2018 under registration number NTR6687.

Each participating centre will obtain approval of the Medical Ethics Committee of the UMC Utrecht before recruitment of patients can start. Furthermore, each participating centre has to comply to local regulations, most of which involve approval by their Board of Directors to participate in a multicentre trial.

Consent to participate is ensured in the following way: eligible women will receive oral and written information from their gynaecologist or fertility physician, and additional counselling will be given by the investigator or research nurse after one week to allow the women to make an informed decision on trial participation. Randomization will then be performed after both the patient and the researcher have signed a written informed consent. Tissue will be stored in the Biobank for future research after patients have given broad written consent.

Consent for publication

Not applicable.

Competing interests

The authors declare that they have no competing interests.

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Figures

Fig. 1
Fig. 1
Study flowchart. LH, luteinizing hormone. LN2, liquid nitrogen. UMCU, University Medical Centre Utrecht. IUI, intrauterine insemination. IVF, in vitro fertilization. EGP, endometrial genetic profile. The boxes in pink apply to the nested cohort study
Fig. 2
Fig. 2
Study time schedule according to SPIRIT (Standard Protocol Items: Recommendations for Interventional Trials)-t1, pre-study period. t0, allocation. t1, post-allocation period; women allocated to the endometrial scratch will undergo this procedure in the same or next month after randomization, in the luteal phase of the natural cycle (6 to 7 days after a positive ovulation test). t2, 12 months after allocation, at which a follow-up questionnaire will be sent to all women who have completed 12 months of follow-up. t3, period in which follow-up of women with an ongoing pregnancy, within 12 months after randomization, will continue until live birth. t4, close-out period. SAE, severe adverse events
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References

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