Multicentric, prospective observational data show sperm capacitation predicts male fertility, and cohort comparison reveals a high prevalence of impaired capacitation in men questioning their fertility.

RESEARCH QUESTIONS: Can a previously defined relationship between sperm capacitation and the probability of a man generating pregnancy within three cycles, prospectively predict male fertility in diverse clinical settings? A second study asked, what is the prevalence of impaired sperm fertilizing ability in men questioning their fertility (MQF), and does this relate to traditional semen analysis metrics? DESIGN: In the multicentric, prospective observational study, data (n = 128; six clinics) were analysed to test a published relationship between the percentage of fertilization-competent, capacitated spermatozoa (Cap-Score) and probability of generating pregnancy (PGP) within three cycles of intrauterine insemination. Logistic regression of total pregnancy outcomes (n = 252) assessed fit. In the cohort comparison, Cap-Scores of MQF (n = 2155; 22 clinics) were compared with those of 76 fertile men. RESULTS: New outcomes (n = 128) were rank-ordered by Cap-Score and divided into quintiles (25-26 per group); chi-squared testing revealed no difference between predicted and observed pregnancies (P = 0.809). Total outcomes (n = 252; 128 new + 124 previous) were pooled and the model recalculated, yielding an improved fit (P < 0.001). Applying the Akaike information criterion found that the optimal model used Cap-Score alone. Cap-Scores were performed on 2155 men (with semen analysis data available for 1948). To compare fertilizing ability, men were binned by PGP (≤19%, 20-29%, 30-39%, 40-49%, 50-59%, ≥60%). Distributions of PGP and the corresponding Cap-Scores were significantly lower in MQF versus fertile men (P < 0.001). Notably, 64% of MQF with normal volume, concentration and motility (757/1183) had PGP of 39% or less (Cap-Scores ≤31), versus 25% of fertile men. CONCLUSIONS: Sperm capacitation prospectively predicted male fertility. Impaired capacitation affects many MQF with normal semen analysis results, informing diagnosis versus idiopathic infertility.

Fumarate Hydratase Mutation in a Young Woman With Uterine Leiomyomas and a Family History of Renal Cell Cancer.

BACKGROUND: Heterozygous gene mutations in fumarate hydratase can result in a syndrome characterized by hereditary (cutaneous and uterine) leiomyomatosis and renal cell cancer. This disorder has been described in more than 200 families, but the prevalence of the disease is unknown. CASE: A 22 year-old woman of Bangladeshi lineage presented with menorrhagia and pelvic pain secondary to uterine leiomyomas and underwent an abdominal myomectomy. Because of a family history of renal cell cancer, she was tested for fumarate hydratase mutations and found to be a carrier. As a result of the risk of renal cell cancer associated with this mutation, an annual surveillance plan was initiated. CONCLUSION: Fumarate hydratase gene mutations should be considered in women presenting with leiomyomas and a family history of renal cancer.

PAX7 expression defines germline stem cells in the adult testis.

Spermatogenesis is a complex, multistep process that maintains male fertility and is sustained by rare germline stem cells. Spermatogenic progression begins with spermatogonia, populations of which express distinct markers. The identity of the spermatogonial stem cell population in the undisturbed testis is controversial due to a lack of reliable and specific markers. Here we identified the transcription factor PAX7 as a specific marker of a rare subpopulation of A(single) spermatogonia in mice. PAX7+ cells were present in the testis at birth. Compared with the adult testis, PAX7+ cells constituted a much higher percentage of neonatal germ cells. Lineage tracing in healthy adult mice revealed that PAX7+ spermatogonia self-maintained and produced expanding clones that gave rise to mature spermatozoa. Interestingly, in mice subjected to chemotherapy and radiotherapy, both of which damage the vast majority of germ cells and can result in sterility, PAX7+ spermatogonia selectively survived, and their subsequent expansion contributed to the recovery of spermatogenesis. Finally, PAX7+ spermatogonia were present in the testes of a diverse set of mammals. Our data indicate that the PAX7+ subset of A(single) spermatogonia functions as robust testis stem cells that maintain fertility in normal spermatogenesis in healthy mice and mediate recovery after severe germline injury, such as occurs after cancer therapy.

Gonadal expression of Foxo1, but not Foxo3, is conserved in diverse Mammalian species.

The Foxos are key effectors of the PI3K/Akt signaling pathway and regulate diverse physiologic processes. Two of these factors, Foxo1 and Foxo3, serve specific roles in reproduction in the mouse. Foxo3 is required for suppression of primordial follicle activation in females, while Foxo1 regulates spermatogonial stem cell maintenance in males. In the mouse ovary, Foxo1 is highly expressed in somatic cells (but not in oocytes), suggesting an important functional role for Foxo1 in these cells. Given that invertebrate model species such as Caenorhabditis elegans and Drosophila melanogaster harbor a single ancestral Foxo homolog, these observations suggest that gene duplication conferred a selective advantage by permitting the Foxos to adopt distinct roles in oogenesis and spermatogenesis. Our objective was to determine if the remarkably specific expression patterns of Foxo1 and Foxo3 in mouse gonads (and, by inference, Foxo function) are conserved in diverse mammalian species. Western blotting was used to validate isoform-specific antibodies in rodents, companion animals, farm animals, nonhuman primates, and humans. Following validation of each antibody, immunohistochemistry was performed to ascertain Foxo1 and Foxo3 gonadal expression patterns. While Foxo1 expression in spermatogonia and granulosa cells was conserved in each species evaluated, Foxo3 expression in oocytes was not. Our findings suggest that Foxo3 is not uniquely required for primordial follicle maintenance in nonrodent species and that other Foxos, particularly Foxo1, may contribute to oocyte maintenance in a functionally redundant manner.

Severe hypercalcemia associated with uterine leiomyoma in pregnancy.

BACKGROUND: Uterine leiomyomas are the most common pelvic tumor, and a frequent indication of the need for gynecologic surgery. Although usually asymptomatic, life-threatening cases can occur. We present a case of critical hypercalcemia associated with a leiomyoma during pregnancy with the intention of highlighting the endocrinology of leiomyomas, features shared with malignant neoplasms, and the potential for effects on obstetric outcomes. CASE: A 32-year-old gravid woman with a large leiomyoma presented at 33 5/7 weeks of gestation with critical hypercalcemia requiring intensive care. Postpartum myomectomy cured her hypercalcemia, which was driven by parathyroid hormone-related protein (PTHrP) produced by the tumor. CONCLUSION: Obstetricians should be aware of the existence of humoral hypercalcemia related to leiomyomas and the potential effects on pregnancy.