Endometriosis is a gynecologic condition characterized by the growth of endometrium-like stroma and glandular elements outside of the uterine cavity. The involvement of hormonal dysregulation, specifically estrogen, is well established in the initiation, progression, and maintenance of the condition. Evidence also highlights the association between endometriosis and altered immune states. The human endometrium is a highly dynamic tissue that undergoes frequent remodeling in response to hormonal regulation during the menstrual cycle. Similarly, endometriosis shares this propensity, compounded by unclear pathogenic mechanisms, presenting unique challenges in defining its etiology and pathology. Here, we provide a lens to understand the interplay between estrogen and innate and adaptive immune systems throughout the menstrual cycle in the pathogenesis of endometriosis. Estrogen is closely linked to many altered inflammatory and immunomodulatory states, affecting both tissue-resident and circulatory immune cells. This review summarizes estrogenic interactions with specific myeloid and lymphoid cells, highlighting their implications in the progression of endometriosis.

Introduction: As total hip arthroplasty and total knee arthroplasty procedures are increasingly performed on younger patients with obesity, the optimal approach to preoperative weight management remains undefined. This study explores national trends among US arthroplasty surgeons regarding body mass index (BMI) cutoffs, weight optimization strategies, and weight loss medication usage. Methods: A 28-question national survey was distributed through e-mail to members of the American Association of Hip and Knee Surgeons and shared on professional social media platforms (Facebook, ResearchGate, and LinkedIn) between January 1 and August 5, 2024. Results: Regarding arthroplasty reconstruction fellowship training, 82.58% (441/534) of respondents were fellowship trained, 11.42% (61/534) were not fellowship trained, and 5.99% (32/534) trained in other specialties. In terms of BMI optimization strategies, 82.84% (n = 444/536) recommended structured diet and exercise programs, 77.99% (n = 418/536) recommended dietitian or weight loss specialist programs, and 52.61% (n = 282/536) advocated for bariatric surgery. For total hip arthroplasty, 45.13% of surgeons used a BMI cutoff <40 kg/m ² (n = 241/534), followed by 23.97% advocating for no strict cutoff (n = 128/534). For total knee arthroplasty, 41.65% reported using a cutoff of <40 kg/m ² (n = 222/533), with 24.39% (n = 130/533) reporting no strict BMI cutoff. In addition, 27.62% (n = 58/210) reported that their patients used weight loss medications such as GLP-1 agonists. Notably, 68.0% (n = 356/526) of surgeons allowed up to 1 to 2 years for BMI optimization before surgery. Conclusion: Although many arthroplasty surgeons use BMI cutoffs, many accommodate patients through nonsurgical interventions to facilitate weight loss. These findings indicate that many respondents report a multidisciplinary approach to preoperative BMI optimization.