Aromatase activity has commonly been associated with male infertility characterized by testicular dysfunction with low serum testosterone and/or testosterone to estradiol ratio. In this subset of patients, and particularly in those with hypogonadism, elevated levels of circulating estradiol may establish a negative feedback on the hypothalamic-pituitary-testicular axis by suppressing follicle-stimulating hormone (FSH) and luteinizing hormone (LH) production and impaired spermatogenesis. Hormonal manipulation via different agents such as selective estrogen modulators or aromatase inhibitors to increase endogenous testosterone production and improve spermatogenesis in the setting of infertility is an off-label option for treatment. We carried out a systematic review and meta-analysis of the literature of the past 30 years in order to evaluate the benefits of the use of aromatase inhibitors in the medical management of infertile/hypoandrogenic males. Overall, eight original articles were included and critically evaluated. Either steroidal (Testolactone) or nonsteroidal (Anastrozole and Letrozole) aromatase inhibitors were found to statistically improve all the evaluated hormonal and seminal outcomes with a safe tolerability profile. While the evidence is promising, future prospective randomized placebo-controlled multicenter trials are necessary to better define the efficacy of these medications.

Purpose: Normative male genital measurements are clinically useful and temporal changes would have important implications. The aim of the present study is to characterize the trend of worldwide penile length over time. Materials and Methods: A systematic review and meta-analysis using papers from PubMed, Embase, and Cochrane Library from inception to April 2022 was performed. PRISMA guidelines were used for abstracting data and assessing data quality and validity. Pooled means and standard deviations for flaccid, stretched, and erect length were obtained. Subgroup analyses were performed by looking at differences in the region of origin, population type, and the decade of publication. Metaregression analyses were to adjusted for potential confounders. Results: Seventy-five studies published between 1942 and 2021 were evaluated including data from 55,761 men. The pooled mean length estimates were flaccid length: 8.70 cm (95% CI, 8.16–9.23), stretched length: 12.93 cm (95% CI, 12.48–13.39), and erect length: 13.93 cm (95% CI, 13.20–14.65). All measurements showed variation by geographic region. Erect length increased significantly over time (QM=4.49, df=2, p=0.04) in several regions of the world and across all age groups, while no trends were identified in other penile size measurements. After adjusting for geographic region, subject age, and subject population; erect penile length increased 24% over the past 29 years. Conclusions The average erect penis length has increased over the past three decades across the world. Given the significant implications, attention to potential causes should be investigated.

Purpose: Medicinal and recreational cannabis use has grown exponentially, however, its effect on testicular function and spermatogenesis remains uncertain. The aim of this study was to evaluate the association between cannabis use and semen parameters in a cohort of Asian-American men with unknown fertility. Materials and Methods: Asian men were recruited to complete an online survey and submit a semen sample. Semen analysis, demographic data, lifestyle factors, and cannabis use habits were collected. Linear and logistic regression analyses were used to determine. Results: Among the 112 men included in this study, 51 used cannabis at least once in their lifetime, 30 men used cannabis at least once in the last 12 months, and 26 men used cannabis at least once in the last 30 days. Adjusted linear regression analyses identified an association between cannabis use in the previous 30 days and worse sperm morphology (β: -0.45, p=0.025) and sperm motility (β: -1.64, p=0.016). However, when stratifying by subfertile semen quality (i.e., WHO criteria), no association was identified between semen quality and cannabis use. Lower sperm morphology and motility are partially associated with recent cannabis use, while all other semen parameters are not. Conclusions We did not observe any consistent associations between cannabis use on any semen parameters in Asian-American men. Further studies within the field are needed to explore racial and ethnic differences in semen quality and lifestyle factors.