Deep EndometriosisEFFORTNCT04610710
Impact of Operation on Fertility for Women With Severe Endometriosis
A study testing Operation and Fertility treatment in people with Deep Endometriosis and Infertility, Female, run by Horsens Hospital at 3 sites in 2 countries.
Trial summary
The EFFORT study compares the impact on fertility of operation or fertility treatment (IVF, in vitro fertilization) in a multicenter randomized controlled trial. The study population consists of women with colorectal deep infiltrating endometriosis and a pregnancy intention. Read more about this study
- Who is it for?
- Ages 18 to 38 years, women only
- Conditions the study is for
- Deep Endometriosis, Infertility, Female
- What is being tested?
- Operation and Fertility treatment
- Type of treatment
- Injection or infusion, Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 38 participants
- Where
- 3 sitesin 2 countries
- Study dates
- 25 Nov 2020to 1 Mar 2026
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 38 years
- Women only
- No healthy volunteers
- Adult
Who may be able to join
- Rectosigmoid endometriosis and wish for surgery
- Pregnancy intention for at least 6 months
- AMH above 5 pmol/ml
- Maximum of 2 previous IVF treatments
- Male partner
Who cannot join
- Endometriosis involving the ureter unilaterally or bilaterally (randomization unethical)
- BMI above 32
- Contraindication for IVF (untreated uterine factor infertility, untreated/maltreated systemic or malignant disease, oocyte aspiration severely riskful (e.g. severe abdominal adhesions)
- No wish for randomization
Trial locations and contacts
3 sites in 2 countries.
3 sites in 2 countries
Denmark2 sites
Aarhus University Hospital
Aarhus N, Central Region, 8200
Horsens Regional Hospital
Horsens, Central Region, 8700
About this study
Official title: Comparing Impact of Operation and Fertility Treatment on Fertility for Women With Deep Infiltrating Endometriosis: A Multicenter Randomized Controlled Trial
The EFFORT study compares the impact on fertility of operation or fertility treatment (IVF, in vitro fertilization) in a multicenter randomized controlled trial. The study population consists of women with colorectal deep infiltrating endometriosis and a pregnancy intention. These women will be randomized to either of the two treatment groups: Group A = Operation or Group B = fertility treatment (IVF). Group A will be further divided postoperatively into spontaneous conception or IVF depending on the Endometriosis Fertility Index score.
- Conditions
- Deep Endometriosis, Infertility, Female
- Being tested
- Operation, Fertility treatment
- Medical subject headings
- Infertility, Female
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
OperationProcedure or surgery
Operation for deep infiltrating endometriosis
Fertility treatmentProcedure or surgery
In vitro fertilisation (IVF) and IVF-intracytoplasmic injection (ICSI)
| Study group | Role | What they receive |
|---|---|---|
| Operation | Active comparator | Operation for severe endometriosis Receives: Procedure: Operation |
| Fertility treatment | Active comparator | Fertility treatment for women with severe endometriosis. Receives: Procedure: Fertility treatment |
What is being measured
The primary outcome is the main question the study is designed to answer.
Cumulative pregnancy rate (CPR)
Rate of cumulative pregnancies defined as a fetal heartbeat by ultrasound at gestational week 6 to 8
Measured: 18 months
Live birth rate (LBR)
Rate of live births
Measured: 18 months
Secondary outcomes (12)
Non-viable pregnancies
Number of biochemical pregnancies, miscarriages, missed abortions, extrauterine pregnancies and pregnancies of unknown location (PUL)
Measured: 18 months
Ovarian potential
Concentration of Anti-Müllerian hormone (AMH)
Measured: Baseline and 9-18 months
Time to pregnancy
Shortest time from intervention date to date of visualisation of the first ongoing pregnancy
Measured: 18 months
Postoperative complications
Rate of complications in accordance to Clavien-Dindo Classification, including anastomotic leakage or stenosis, ureteral lesion or obstruction, pelvic abscess, fistula, bladder or bowel perforation and urinary retention
Measured: 18 months
Fertility treatment complications
Rate of hospital admissions, bleeding, superinfection, worsening of pain or having ovarian hyperstimulation syndrome (OHSS)
Measured: 18 months
Pain score
Numeric Rating Scale (NRS) score from 0 to 10, where 10 implies the worst pain
Measured: Baseline, 9 and 18 months
Quality of Life (QoL)
Development in Endometriosis Health Profile (EHP-30+23), including section C (sexual function QoL questions) and section F (fertility QoL questions)
Measured: Baseline, 9 and 18 months
Delayed bowel function
Development in bowel function rated by Low Anterior Resection Syndrome (LARS) score
Measured: Baseline, 9 and 18 months
Delayed bladder function
Development in urinary tract function rated by International Consultation on Incontinence Questionnaire (ICIQ- FLUTS)
Measured: Baseline, 9 and 18 months
Endometriosis hormonal and inflammatory status
Concentrations of hormonal and inflammatory markers in blood samples
Measured: Baseline and 9-18 months
Follicles, oocytes, fertilized oocytes, blastocysts, and frozen embryos
Number of follicles as measured at last scan prior to oocyte pick-up (OPU), number of oocytes at OPU, fertilized oocytes, blastocysts and frozen embryos
Measured: 18 months
Blastocyst morphology score
Gardner scoring system, Steer grading system, Veecks criteria, or other scoring systems of blastocyst morphology
Measured: 18 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted30 Oct 2020
- Study start25 Nov 2020
- Primary completion1 Mar 2026
- Study completion1 Mar 2026
Why it stopped: Enrolment of study participants was too challenging and long-drawn.
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (2)Papers the sponsor has linked to this study.
- Other trials for Deep EndometriosisStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Randomized Clinical Trail (RCT)
- Masking
- None (open label)
- Enrolment
- 38 participants (actual)
Sponsor and investigators
- Lead sponsor
- Horsens Hospital
- Sponsor type
- University, hospital or other
- Collaborators
- Aarhus University Hospital, Clinique Tivoli Ducos
- Responsible party
- Principal investigator, Ulla Breth Knudsen, Horsens Hospital
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04610710
- Sponsor's protocol ID
- Horsens MR
- Acronym
- EFFORT
- Status last verified
- Mar 2025
- First submitted
- 22 Oct 2020
- Last updated
- 10 Mar 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Raos M, Seyer-Hansen M, Kesmodel US, Knudsen UB, Roman H. EFFORT study: Surgery vs assisted reproductive technology among women with deep endometriosis - A multicenter randomized controlled trial. Eur J Obstet Gynecol Reprod Biol. 2026 Aug 3;326:115350. doi: 10.1016/j.ejogrb.2026.115350. Online ahead of print.
PubMed 42617331Raos M, Roman H, Seyer-Hansen M, Kesmodel US, Knudsen UB. EFFORT study: Comparing impact of operation and assisted reproductive technologies on fertility for women with deep infiltrating endometriosis - study protocol for a multicentre randomised trial. BMJ Open. 2022 Apr 11;12(4):e052877. doi: 10.1136/bmjopen-2021-052877.
PubMed 35410921
Study at a glance
From the registry record, last updated by the sponsor on 10 Mar 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Comparing Impact of Operation and Fertility Treatment on Fertility for Women With Deep Infiltrating Endometriosis: A Multicenter Randomized Controlled Trial
- ClinicalTrials.gov ID
- NCT04610710
- Acronym / sponsor ID
- EFFORT / Horsens MR
- Conditions
- Deep Endometriosis, Infertility, Female
- Study type
- Interventional
- Recruitment status
- TerminatedReason stopped: Enrolment of study participants was too challenging and long-drawn.
- Enrolment
- 38 participants (actual)
- Lead sponsor
- Horsens HospitalUniversity, hospital or other
- Collaborators
- Aarhus University Hospital, Clinique Tivoli Ducos
- Study start
- 25 Nov 2020 (actual)
- Primary completion
- 1 Mar 2026 (actual)
- Study completion
- 1 Mar 2026 (actual)
- First posted
- 30 Oct 2020 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The EFFORT study compares the impact on fertility of operation or fertility treatment (IVF, in vitro fertilization) in a multicenter randomized controlled trial. The study population consists of women with colorectal deep infiltrating endometriosis and a pregnancy intention. These women will be randomized to either of the two treatment groups: Group A = Operation or Group B = fertility treatment (IVF). Group A will be further divided postoperatively into spontaneous conception or IVF depending on the Endometriosis Fertility Index score.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- Randomized Clinical Trail (RCT)
| Arm | Type | Receives |
|---|---|---|
| Operation | Active comparator | Procedure: OperationOperation for severe endometriosis |
| Fertility treatment | Active comparator | Procedure: Fertility treatmentFertility treatment for women with severe endometriosis. |
Who may qualify
- Ages
- 18 to 38 years
- Sex
- Female only
- Healthy volunteers
- Not accepted
- Age groups
- Adult
Key inclusion criteria (5 listed)
- Rectosigmoid endometriosis and wish for surgery
- Pregnancy intention for at least 6 months
- AMH above 5 pmol/ml
- Maximum of 2 previous IVF treatments
- Male partner
Key exclusion criteria (4 listed)
- Endometriosis involving the ureter unilaterally or bilaterally (randomization unethical)
- BMI above 32
- Contraindication for IVF (untreated uterine factor infertility, untreated/maltreated systemic or malignant disease, oocyte aspiration severely riskful (e.g. severe abdominal adhesions)
- No wish for randomization
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| OperationOperation for deep infiltrating endometriosis | Procedure or surgery | Operation |
| Fertility treatmentIn vitro fertilisation (IVF) and IVF-intracytoplasmic injection (ICSI) | Procedure or surgery | Fertility treatment |
Primary outcome
Cumulative pregnancy rate (CPR)
Time frame: 18 months
Rate of cumulative pregnancies defined as a fetal heartbeat by ultrasound at gestational week 6 to 8
Live birth rate (LBR)
Time frame: 18 months
Rate of live births
12 secondary outcomes
Non-viable pregnancies
Time frame: 18 months
Ovarian potential
Time frame: Baseline and 9-18 months
Time to pregnancy
Time frame: 18 months
Postoperative complications
Time frame: 18 months
Fertility treatment complications
Time frame: 18 months
Pain score
Time frame: Baseline, 9 and 18 months
Quality of Life (QoL)
Time frame: Baseline, 9 and 18 months
Delayed bowel function
Time frame: Baseline, 9 and 18 months
Delayed bladder function
Time frame: Baseline, 9 and 18 months
Endometriosis hormonal and inflammatory status
Time frame: Baseline and 9-18 months
Follicles, oocytes, fertilized oocytes, blastocysts, and frozen embryos
Time frame: 18 months
Blastocyst morphology score
Time frame: 18 months
Results and safety
The study was stopped early (reason given: Enrolment of study participants was too challenging and long-drawn.). Results are not available in the source record.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 10 Mar 2026.
- Derived from this study: PubMed 42617331Raos M, Seyer-Hansen M, Kesmodel US, Knudsen UB, Roman H. EFFORT study: Surgery vs assisted reproductive technology among women with deep endometriosis - A multicenter randomized controlled trial. Eur J Obstet Gynecol Reprod Biol. 2026 Aug 3;326:115350. doi: 10.1016/j.ejogrb.2026.115350. Online ahead of print.
- Derived from this study: PubMed 35410921Raos M, Roman H, Seyer-Hansen M, Kesmodel US, Knudsen UB. EFFORT study: Comparing impact of operation and assisted reproductive technologies on fertility for women with deep infiltrating endometriosis - study protocol for a multicentre randomised trial. BMJ Open. 2022 Apr 11;12(4):e052877. doi: 10.1136/bmjopen-2021-052877.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
3 sites in 2 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Operation and Fertility treatment in people with Deep Endometriosis and Infertility, Female, run by Horsens Hospital at 3 sites in 2 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: stopped early, as of the sponsor's last update on 10 Mar 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 3 sites in Denmark, France. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study was stopped early (reason given: Enrolment of study participants was too challenging and long-drawn.). Results are not available in the source record.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Cumulative pregnancy rate (CPR) (time frame: 18 months). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT04610710, which also lists 2 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 10 Mar 2026.