Mid to late luteal phase steroids in minimal stage endometriosis and unexplained infertility

Endogenous Steroid Hormone Concentrations and Risk of Endometriosis in Nurses' Health Study II

Few studies have assessed the association between endogenous steroid hormone levels and a subsequent diagnosis of endometriosis. We prospectively evaluated premenopausal plasma sex hormone levels and the risk of laparoscopically confirmed endometriosis in a nested case-control study within Nurses' Health Study II. Between blood collection (1996-1999) and 2009, we ascertained 446 women with incident endometriosis and matched them to 878 controls through risk-set sampling. We conducted multivariable conditional logistic regression accounting for matching and confounders to estimate relative risks (RRs) and 95% confidence intervals (CIs). Women with greater early follicular-phase total or free estradiol levels had a nonlinear increased risk of endometriosis (early follicular total estradiol: second quartile vs. first, RR = 2.23 (95% CI: 1.44, 3.47); third quartile, RR = 1.83 (95% CI: 1.16, 2.88); fourth quartile, RR = 1.68 (95% CI: 1.05, 2.68); early follicular free estradiol: second quartile vs. first, RR = 1.63 (95% CI: 1.05, 2.54); third quartile, RR = 2.02 (95% CI: 1.31, 3.12); fourth quartile, RR = 1.04 (95% CI: 0.66, 1.65)). Free testosterone assessed in quartile categories was not associated with endometriosis, although a threshold effect was observed, with a positive association among women in the top 2% of free testosterone levels. Levels of mid-luteal-phase total and free estradiol, follicular and luteal estrone, total testosterone, progesterone, and sex hormone binding globulin were not associated with endometriosis risk. These results support the role of sex steroids in endometriosis etiology, although the relationships suggest complex threshold effects.

Endogenous progesterone in unexplained infertility: a systematic review and meta-analysis

PURPOSE

To investigate the possibility that altered actions of endogenous progesterone affect receptivity and contribute to unexplained infertility (UI).

METHODS

Two authors electronically searched MEDLINE, CINAHL and Embase databases from inception to 6 July 2022 and hand-searched according to Cochrane methodology. We included all published primary research reporting outcomes related to endogenous progesterone in natural cycles in women with UI. Studies were assessed for risk of bias using a modified Newcastle-Ottawa Score or NHLBI Score. We pooled results where appropriate using a random-effects model. Findings were reported as odds ratios or mean differences.

RESULTS

We included 41 studies (n = 4023). No difference was found between the mid-luteal serum progesterone levels of women with UI compared to fertile controls (MD 0.74, - 0.31-1.79, I² 36%). Women with UI had significantly higher rates of 'out-of-phase' endometrium than controls. Nine out of 10 progesterone-mediated markers of endometrial receptivity were significantly reduced in women with UI compared to fertile controls (the remaining 1 had conflicting results). Resistance in pelvic vessels was increased and perfusion of the endometrium and sub-endometrium reduced in UI compared to fertile controls in all included studies. Progesterone receptor expression and progesterone uptake were also reduced in women with unexplained infertility.

CONCLUSIONS

End-organ measures of endogenous progesterone activity are reduced in women with UI compared to fertile controls. This apparently receptor-mediated reduction in response affects endometrial receptivity and is implicated as the cause of the infertility. Further research is required to confirm whether intervention could overcome this issue, offering a new option for treating unexplained infertility.

TRIAL REGISTRATION

PROSPERO registration: CRD42020141041 06/08/2020.

Pathogenesis of endometriosis: Interaction between Endocrine and inflammatory pathways

Despite an estimated prevalence of 11% in women and plausible historical descriptions dating back to the 17th century, the etiology of endometriosis remains poorly understood. Classical theories of the histological origins of endometriosis are reviewed below. Clinical presentations are variable, and signs and symptoms do not correlate well with the extent of disease. In this summary, we have attempted to synthesize the growing evidence that hormonal and immune factors conspire to activate a local inflammatory microenvironment that encourages endometriosis to persist and elaborate mediators of its two cardinal symptoms: pain and infertility. Surprisingly, in the search for novel therapeutics for medical treatment of endometriosis, some compounds appear to have dual pharmacological functions, simultaneously modifying the endocrine and immune system facets of this complex gynecologic syndrome. We predict that these lead drugs will provide more therapeutic choices for patients in the future.

Pathogenesis of Endometriosis: Roles of Retinoids and Inflammatory Pathways

Endometriosis is a nonmalignant, but potentially metastatic, gynecological condition manifested by the extrauterine growth of inflammatory endometrial implants. Ten percent of reproductive-age women are affected and commonly suffer pelvic pain and/or infertility. The theories of endometriosis histogenesis remain controversial, but retrograde menstruation and metaplasia each infer mechanisms that explain the immune cell responses observed around the ectopic lesions. Recent findings from our laboratories and others suggest that retinoic acid metabolism and action are fundamentally flawed in endometriotic tissues and even generically in women with endometriosis. The focus of our ongoing research is to develop medical therapies as adjuvants or alternatives to the surgical excision of these lesions. On the basis of concepts put forward in this review, we predict that the pharmacological actions and anticipated low side-effect profiles of retinoid supplementation might provide a new treatment option for the long-term management of this chronic and debilitating gynecological disease.

Paracrine regulation of endometriotic tissue

Endometriosis is a chronic estrogen-dependent gynecological disease, characterized by pelvic pain and infertility, defined as the presence of endometrial glands and stroma within the pelvic peritoneum and other extrauterine sites. In the peritoneal cavity endometrial cells adhere, proliferate and induce an inflammatory response. Despite a long history of clinical and experimental research, the pathogenesis of endometriosis is still controversial. Abnormal immunological activation, the endocrine milieu and the peritoneal environment all dramatically affect endometriotic tissue function. Recent studies suggest that the peritoneal fluid of women with endometriosis contains an increased number of activated macrophages and other immune cells that secrete various local products, such as growth factors and cytokines, which exert a paracrine action on endometriotic cells. Since the peculiar biological characteristics of eutopic endometrium from women with endometriosis differ from endometrium of normal subjects, an important role in the pathogenesis of this complex disease has been suggested. All of these factors contribute to enhanced proliferative and angiogenic activity and a number of functional and structural changes, resulting in the particular behavior of this tissue.

Physiopathological aspects of corpus luteum defect in infertile patients with mild/minimal endometriosis

PURPOSE

We describe a physiopathological model to the luteal insufficiency of infertile patients with mild/minimal endometriosis with normal hormone measurements in the early follicular phase.

METHODS

We designed a case-control study with 24 patients, 14 fertile with in-phase endometrium (control group) and 10 infertile with mild/minimal endometriosis and luteal insufficiency (study group). The histologic dating of endometrium was performed during cycle days 23-25 and serum TSH, FSH, LH, prolactin, and estradiol levels were measured during the early follicular phase (cycle day 3). Progesterone serum levels were measured in three different occasions during the luteal phase.

RESULTS

Patients with out-of-phase endometrium have lower estradiol levels (P = 0.031) and decreased progesterone secretion (P = 0.012) during the late luteal phase. Serum prolactin, TSH, FSH, and LH levels were similar between the groups (P > 0.05).

CONCLUSIONS

The physiopathology of luteal phase defect in infertile patients with mild/minimal endometriosis is associated with a small and large luteal cells dysfunction, characterized by abnormal follicular phase (lower estradiol serum levels) and lower progesterone LH-dependent secretion.