Endometriosis Longitudinal Fertility Study (ELFS): a prospective longitudinal cohort study of the effect of conservative and surgical management for moderate to severe endometriosis on future fertility – study protocol
Samantha Mooney, Vanessa Ross, Uri P Dior, Charlotte Reddington, Lauren Hicks, Claudia Cheng, Michal Amir, Keryn Harlow, Sarah Holdsworth-Carson, Kate Stern, Martin Healey, Peter RogersIntroduction
Endometriosis is associated with reduced pregnancy and live birth rates in patients attempting both spontaneous and assisted conception. At present, it is unclear whether prepregnancy surgery for moderate or severe endometriosis, either in the setting of established infertility or even before a woman has begun trying to conceive, confers any benefit in terms of (a) spontaneous conception, (b) conception with assisted reproductive technology (ART), (c) live birth or (d) other obstetric outcomes.
Methods and analysis
The Endometriosis Longitudinal Fertility Study (ELFS) is a multisite prospective longitudinal cohort study, recruiting patients <38 years of age with evidence of moderate or severe endometriosis (revised American Society of Reproductive Medicine grades 3 or 4) who desire fertility immediately or in the near future. ELFS aims to longitudinally assess clinical pregnancy and live birth rates for women with moderate or severe endometriosis who choose to have no treatment, fertility treatment and/or surgery. The target sample size was determined by a simulation-based power calculation. The study will comprise 700 participants: 400 attempting natural conception and 300 attempting to conceive with ART. Each of these cohorts will be divided evenly between the conservative and surgical management groups. Following consent and baseline questionnaire, participants instal the purpose-built ELFS App to their mobile phone. The participant then receives cyclical surveys at intervals based on their menstrual cycle, with timing dependent on learnt logic from prior responses. Participants conclude participation following a live birth beyond 20-week gestation. The primary research outcome is to compare the ‘per cycle’ clinical pregnancy rate and live birth rate where endometriosis is managed conservatively or surgically in those conceiving naturally or with assisted reproductive techniques. Secondary outcomes include exploring menstrual cycle characteristics and examining the obstetric outcomes of women with moderate and severe endometriosis who successfully conceive. The outcomes of this research aim to contribute to improving endometriosis management for women desiring pregnancy by establishing if there is a fertility benefit of prepregnancy surgery in patients with moderate or severe endometriosis.
Ethics and dissemination
The Austin Health Ethics Committee approved the ELFS protocol (HREC/65683/Austin-2020). On study completion, results of the trial will be submitted for publication in a peer-reviewed journal. Interim experiences with the ELFS App as well as relevant secondary outcomes will be presented at international conferences with additional goals for publication.
Trial registration number
ACTRN12621000431820.