Preface

Endometriosis has the potential to disrupt the lives of women of reproductive age through several manifestations: dysmenorrhea, dyspareunia, chronic pelvic pain, and subfertility. This issue focuses on subfertility with the goal of elaborating the consequences of endometriosis on fertility while providing actionable recommendations. Decisions to optimize fertility are fraught with conflicting studies or the lack of rigorous well-designed clinical trials. To the best of their discerning eyes and astute minds, the contributing authors have sorted through the medical literature to provide us with the strongest evidence-based conclusions.

Advances in fertility care have added to the level of complexity in treating women with endometriosis. More options beget more questions as to the most appropriate next steps in managing infertility. Each author contribution tackles specific questions, yet readers will appreciate the overlap in topic discussion from article to article. These intersecting issues are inevitable but do serve a worthy purpose in their repetition. Because the literature can be confusing, it helps to read how these scholars synthesized the data to lead to their learned conclusions. Besides which, repetition can often assuage clinicians and researchers in general.

This issue begins with a review by Tomassetti et al on the association and causation of adenomyosis and subfertility. Adenomyosis is often seen in conjunction with endometriosis. Overall, using evidence-based medicine, they provide “evidence to support a causal association between adenomyosis and subfertility.”

Lessey et al review the importance of the endometrium vis-à-vis endometriosis and implantation. “The endometrium is ground zero when it comes to understanding how implantation occurs and how it might also fail.” The eutopic endometrium is altered in women with endometriosis, thereby negatively influencing the window of implantation. These authors comprehensively review the endometrial changes that may lead to more efficacious treatment.

Grümmer provides a review of the experimental animal models used to study subfertility from endometriosis. Because several factors can lead to the reduced fecundity, “further studies are needed to decipher whether ovarian, gamete, embryo, endometrial, and/or immunological abnormalities reduce fecundity in affected women.” Understanding the different animal models elucidated by Grümmer will help researchers design studies to answer critical questions leading to improvements in endometriosis-associated infertility.

Berlanda et al tackle the role of surgery in endometriosis-associated infertility. “When considering surgery, a therapeutic equipoise should be reached that includes demonstrated benefits, potential morbidity, and costs of treatment alternatives.” Surgery is never trivial, and thus these authors effectively synthesize the available evidence (often conflicting) on the merits of conservative surgery in this subpopulation of infertile women. They provide concrete practice guidelines for several difficult clinical scenarios.

Shah peers into the possible insult (diminished ovarian reserve) upon injury (endometriosis) and “whether the impact of endometriosis on ovarian reserve markers translates into an adverse impact on pregnancy outcome.” Many unanswered questions on this topic are clearly laid out in this article.

Kavoussi evaluates “if subtle or overtly aberrant follicular development is thought to contribute to endometriosis-associated infertility, does superovulation provide benefit in women with minimal to mild endometriosis?” Virtually no two studies were designed similarly, but this article makes the most out of the data to offer sound recommendations.

Surrey analyzes the impact of endometriosis on in vitro fertilization outcome and the role of surgical or medical interventions. For instance, “the administration of a prolonged course of GnRH agonists, and possibly other suppressive agents, appears to improve IVF cycle outcome.” This review goes even further by delineating the gaps in our knowledge base while still providing practical suggestions for enhancing assisted reproductive technology outcomes.

Flyckt et al address the optimal strategies of managing endometriomas in those using assisted reproductive technology. They explain the many caveats to published studies on this topic and provide salient recommendations. For instance, “destruction of the cyst wall need not be deep because endometriosis generally penetrates <2 mm into the cyst wall.”

Hauzman et al offer an all-inclusive review of the data on donated oocytes into endometriosis recipients because “oocyte donation provides an interesting model to investigate reproductive outcome as factors affecting the oocytes are excluded.” Important caveats are provided to enable readers to better evaluate such studies in the future.

Lastly, Falconer explores what happens to women with endometriosis after conception and into their pregnancy. Namely, this article “summarizes the known adverse pregnancy outcomes caused by endometriosis and their possible underlying mechanisms.”

I am grateful to Bruce Carr and Serdar Bulun for the privilege to edit this issue of Seminars in Reproductive Medicine. Interacting with these talented contributors and noted endometriosis experts has been an honor. I hope readers will learn from their guidance and patients will reap the benefits.