Fertility preservation (FP) is an established and recognised intervention for those undergoing gonadotoxic treatments, principally for malignancy. The surgical treatment of endometrioma and the disease itself reduce ovarian reserve and has sparked debate on whether FP should be offered prior to treatment.¹

The association between endometriosis and infertility is accepted but uncertain as to aetiology and pathophysiology. A direct causation between surgery for ovarian endometrioma and reduced ovarian reserve may not be as clear as previously considered. Histological analyses confirm cortical follicular density and percentage of atretic follicles are negatively impacted within ovaries containing endometriomas compared with unaffected ovaries.² This suggests that damage to the ovarian reserve may be partially inherent to the condition rather than iatrogenic, with no high-quality evidence to support or refute the role of surgery ahead of ovarian stimulation.³ Tests used to assess ovarian reserve such as anti-mullerian hormone and antral follicle count are highly predictive of ovarian response during ovarian stimulation, with the cumulative live birth rate directly linked to oocyte yield in FP,⁴ but these tests do not predict future fertility, fecundity or spontaneous conception. This is important for a cohort of patients considering FP having never tried to conceive.

When considering tangible outcomes, important to patients, the live birth rate does not differ among those undergoing surgery and expectant management of ovarian endometrioma ahead of in vitro fertilisation with enhanced spontaneous conception for those undergoing surgery.³ The largest observational studies of over 400 patients with endometrioma undergoing FP concluded that oocyte yield is lower for those having undergone surgery for endometrioma; however, there were no statistical differences in cumulative live birth rate in operated, unoperated and controls.⁴

The indication for FP in women with ovarian endometriosis remains unclear, as the natural history of endometriosis is poorly understood. The use of hormonal secondary prevention following cytoreductive surgery is safe, effective and recommended for patients with symptomatic ovarian endometriosis.¹ Fertility preservation will be unnecessary for many and particularly young patients with normal or high ovarian reserve. This pre-emptive intervention may contribute to health-related anxiety and influence future health decision-making without the guarantee of a live birth.

Globally, the fertility sector is variably regulated, with many non-evidenced based interventions offered. In the UK, the Human Fertilisation and Embryology Authority regulates oocyte storage, but understanding the optimal approach to FP is hindered by low-quality efficacy data on ovarian tissue cryopreservation, limited to case reports,⁵ and no assessment of harm. In the UK, the National Institute of Health and Care Excellence recommend that services are not considered for implementation prior to a robust cost-effectiveness analysis. It is evidently clear that both clinicians and regulatory bodies currently lack high-quality evidence to endorse routine usage of fertility preservation among women with ovarian endometrioma.⁶

We strongly advise against implementing a further fertility intervention until robust, impartial, randomised controlled trial data, including cost effectiveness, and patient perspectives can enable prognostic modelling for clinical guideline development in a nationally funded healthcare system.

生育力保留 (FP) 是一种既定且公认的干预措施，适用于接受性腺毒性治疗的患者，主要针对恶性肿瘤。子宫内膜异位症的手术治疗和疾病本身会减少卵巢储备，并引发了关于是否应在治疗前提供 FP 的争论。¹

子宫内膜异位症和不孕症之间的关联是公认的，但在病因学和病理生理学方面尚不确定。卵巢子宫内膜异位症手术与卵巢储备减少之间的直接因果关系可能不像以前考虑的那样清楚。组织学分析证实，与未受影响的卵巢相比，含有子宫内膜异位症的卵巢内的皮质卵泡密度和闭锁卵泡的百分比受到负面影响。²这表明卵巢储备的损害可能部分是该病症固有的，而不是医源性的，没有高质量的证据支持或反驳在卵巢刺激之前进行手术的作用。³用于评估卵巢储备的测试，如抗苗勒管激素和窦卵泡计数，可以高度预测卵巢刺激期间的卵巢反应，累积活产率与 FP 中的卵母细胞产量直接相关，⁴但这些测试不能预测未来的生育能力，繁殖力或自发受孕。这对于考虑 FP 且从未尝试过怀孕的一组患者来说非常重要。

在考虑对患者很重要的有形结果时，接受手术的患者和接受体外受精前卵巢子宫内膜异位症的预期治疗的患者的活产率没有差异，接受手术的患者自发受孕增强。³对 400 多名接受 FP 的子宫内膜异位症患者的最大观察性研究得出结论，接受子宫内膜异位症手术的患者的卵母细胞产量较低；然而，手术、未手术和对照组的累积活产率没有统计学差异。⁴

由于对子宫内膜异位症的自然史知之甚少，卵巢子宫内膜异位症女性的 FP 适应症仍不清楚。对于有症状的卵巢子宫内膜异位症患者，在细胞减灭手术后使用激素二级预防是安全、有效的并被推荐。¹对于许多卵巢储备正常或较高的年轻患者，尤其是年轻患者来说，保留生育能力是不必要的。这种先发制人的干预可能会导致与健康相关的焦虑，并在无法保证活产的情况下影响未来的健康决策。

在全球范围内，生育部门受到不同程度的监管，提供了许多基于非证据的干预措施。在英国，人类受精和胚胎学管理局对卵母细胞储存进行监管，但了解 FP 的最佳方法受到卵巢组织冷冻保存的低质量疗效数据的阻碍，仅限于病例报告⁵并且没有评估危害。在英国，国家健康与护理卓越研究所建议在进行稳健的成本效益分析之前不考虑实施服务。很明显，临床医生和监管机构目前都缺乏高质量的证据来支持在卵巢子宫内膜异位症女性中常规使用保留生育能力。⁶

我们强烈建议不要实施进一步的生育干预，直到稳健、公正、随机对照试验数据（包括成本效益和患者观点）能够为国家资助的医疗保健系统中临床指南制定的预后建模提供支持。