ATOPE study: what is the optimal surgical strategy for endometriomas in women who wish to become pregnant?
- Marketing IFEM Endo Marketing IFEM Endo
- Dec 30, 2025
- 5 min read
A common clinical dilemma in specialized practice
For women with ovarian endometrioma who wish to become pregnant, choosing a surgical strategy remains a complex decision.
Clinicians must balance disease control, preservation of ovarian reserve, and optimization of pregnancy chances, in a context where high-level comparative data remain limited.
Ovarian endometriomas are a specific form of endometriosis, affecting 17 to 44% of patients with the disease¹. Defined as endometriotic cysts larger than 10 mm, they are frequently associated with chronic, debilitating pelvic pain, impaired fertility, and other endometriotic lesions.
Their presence is correlated with a decrease in spontaneous ovulation and a reduction in the effectiveness of assisted reproductive technology (ART)²,³, raising the crucial question of optimal surgical management.
Three surgical techniques currently in use
Several surgical options are available to treat endometriomas in patients who wish to become pregnant, each with specific benefits and limitations.
Cystectomy
Considered the historical standard⁴, cystectomy involves removing the entire cyst capsule by divergent traction ("stripping"). While this technique provides good control of the disease, it is associated with a loss of healthy ovarian parenchyma proportional to the size of the cyst⁵, leading to a significant decrease in postoperative ovarian reserve⁶⁻⁷, as assessed in particular by AMH (a hormone that reflects ovarian reserve).
Plasma energy vaporization
Plasma vaporization allows for superficial destruction of endometriotic tissue while preserving the ovarian cortex⁸. Recent data suggest a lesser impact on ovarian reserve, with satisfactory pregnancy rates⁹⁻¹¹. This technique is mainly used for endometriomas smaller than or equal to 6 cm.
Sclerotherapy with 95° ethanol
Sclerotherapy involves destroying endometriotic tissue through prolonged contact with ethanol. The protocol developed at IFEMEndo has shown a pregnancy rate of 75% at 36 months, with limited impact on ovarian reserve. This approach is reserved for endometriomas larger than 6 cm.
A major gap in the scientific literature
Despite the increasing use of these different techniques, no prospective randomized study has yet compared these approaches with pregnancy as the primary endpoint.
This lack of randomized comparisons focused on fertility criteria is a real gap in the literature, even though preserving reproductive potential is central to surgical decisions in these patients.
The ATOPE study: answering an unresolved clinical question
It is in this context that IFEM Endo Bordeaux initiated the ATOPE study (Ablative Technique for Ovarian Preservation in Endometrioma – NCT07119060), a trial aimed at comparing the impact of different surgical techniques on fertility.
Main objective: To compare pregnancy rates 24 months after surgical treatment of endometriomas.
Study methodology and design
This is a single-center randomized controlled trial with individual follow-up for 24 months.
Target population: 332 patients included in the randomized arms
Total duration of the study: 108 months, including 84 months of recruitment
Distribution according to endometrioma size
Endometriomas measuring 2 to 6 cm
Randomization between:
Arm A: cystectomy (n = 166)
Arm B: plasma vaporization (n = 166)
Endometriomas > 6 cm
Observational cohort treated with sclerotherapy (without randomization)
Eligible population
The inclusion criteria apply to female patients aged 18 to 43 years with:
symptomatic endometriosis requiring surgical treatment,
at least one endometrioma > 20 mm confirmed by recent MRI or ultrasound,
a probable or certain desire to become pregnant after surgery.
Evaluation criteria
Primary endpoint: pregnancy rate at 24 months (β-HCG > 1000 IU or ultrasound visualization at 5 weeks of gestation).
Secondary criteria:
live birth rate,
method of conception (spontaneous or ART),
endometrioma recurrence,
surgical complications (Clavien-Dindo classification),
pain progression,
AMH progression.
Statistical considerations
The power calculation is based on an expected pregnancy rate of 65% in the plasma vaporization arm versus 50% in the cystectomy arm, with a power of 80% and an α risk of 5%, justifying the inclusion of 166 patients per arm.
Given IFEM Endo's annual activity, the recruitment period is estimated to be approximately 7 years, with results expected at the end of the full follow-up period, scheduled to last until 2033.
An expected contribution to clinical practice
Beyond the methodological challenge, the ATOPE study aims to provide robust comparative data to improve surgical decision-making for patients who wish to become pregnant.
The expected results should help refine the choice of treatment strategy, balancing disease control with optimal fertility preservation.
Through the ATOPE study, IFEMEndo Bordeaux is affirming its position as a leading center committed to producing key clinical data on endometriosis.
This approach aims to strengthen medical decision-making support and improve care for patients who wish to become pregnant.
Kristina Ananian - Clinical research technician
References :
Alson S, Jokubkiene L, Henic E, Sladkevicius P. Prevalence of endometrioma and deep infiltrating endometriosis at transvaginal ultrasound examination of subfertile women undergoing assisted reproductive treatment. Fertil Steril. 2022;118(5):915–23.
Daniilidis A, Grigoriadis G, Kalaitzopoulos DR, Angioni S, Kalkan Ü, Crestani A, et al. Surgical Management of Ovarian Endometrioma: Impact on Ovarian Reserve Parameters and Reproductive Outcomes. Journal of Clinical Medicine. 2023;12(16):5324.
Benaglia L, Bermejo A, Somigliana E, Faulisi S, Ragni G, Fedele L, et al. In vitro fertilization outcome in women with unoperated bilateral endometriomas. Fertil Steril. 2013;99(6):1714–9.
Hart RJ, Hickey M, Maouris P, Buckett W. Excisional surgery versus ablative surgery for ovarian endometriomata. Cochrane Database Syst Rev. 2008;(2):CD004992.
Roman H, Tarta O, Pura I, Opris I, Bourdel N, Marpeau L, et al. Direct proportional relationship between endometrioma size and ovarian parenchyma inadvertently removed during cystectomy, and its implication on the management of enlarged endometriomas. Human Reproduction. 2010;25(6):1428–32.
Becker CM, Bokor A, Heikinheimo O, Horne A, Jansen F, Kiesel L, et al. ESHRE guideline: endometriosis. Human Reproduction Open. 2022;2022(2):hoac009.
Taniguchi F, Sakamoto Y, Yabuta Y, Azuma Y, Hirakawa E, Nagira K, et al. Analysis of pregnancy outcome and decline of anti-Müllerian hormone after laparoscopic cystectomy for ovarian endometriomas. J Obstet Gynaecol Res. 2016;42(11):1534–40.
Stefanovic S, Sütterlin M, Gaiser T, Scharff C, Neumann M, Berger L, et al. Microscopic, Macroscopic and Thermal Impact of Argon Plasma, Diode Laser, and Electrocoagulation on Ovarian Tissue. In Vivo. 2023;37(2):531–8.
Candiani M, Ferrari S, Bartiromo L, Schimberni M, Tandoi I, Ottolina J. Fertility Outcome after CO2 Laser Vaporization versus Cystectomy in Women with Ovarian Endometrioma: A Comparative Study. Journal of Minimally Invasive Gynecology. 2021;28(1):34–41.
Motte I, Roman H, Clavier B, Jumeau F, Chanavaz-Lacheray I, Letailleur M, et al. In vitro fertilization outcomes after ablation of endometriomas using plasma energy: A retrospective case-control study. Gynecol Obstet Fertil. 2016;44(10):541–7.
Crestani A, Merlot B, Dennis T, Roman H. Laparoscopic sclerotherapy for an endometrioma in 10 steps. Fertil Steril. 2022;S0015-0282(22)00071-1.
Crestani A, Merlot B, Dennis T, Chanavaz-Lacheray I, Roman H. Impact of Laparoscopic Sclerotherapy for Ovarian Endometriomas on Ovarian Reserve. J Minim Invasive Gynecol. 2023;30(1):32–8.
