Effect of Preoperative Androgen Stimulation on Penile Size and Postoperative Complication Rate in Patients with Hypospadias: A Systematic Review and Meta-Analysis

Purpose: To systematically review and evaluate the beneficial effects of preoperative androgen stimulation (PAS) on penile length, glans width, and postoperative complications in patients with hypospadias using meta-analysis. Materials and Methods: A comprehensive search of the published literature between 1980 and 2022 was done on PubMed, Embase, Google Scholar, Scopus, Web of Science, and Proquest. Studies of patients with 5-alpha reductase deficiency, differentiation sex disorder, or micro-penis without hypospadias were excluded. The full-text screening, quality assessment, and data acquisition were done independently by two reviewers. Meta-analysis was done to quantify the penile growth and postoperative complications. Results: The initial literature search yielded 2,389 records, wherein 32 studies were eligible for the systematic review and meta-analysis. Preoperative testosterone stimulation increased the penile length and glans width by 9.34 mm (95% CI: 6.71-11.97) and 3.26 mm (95% CI: 2.50-4.02), respectively. A longer penis at the baseline led to greater length gain following treatment (1 mm longer at the baseline was likely to gain 0.5 mm more). However, the increase in penile length was not associated with the severity of hypospadias. While the treatment did not affect the overall complication rate, the postoperative fistula risk was lower in those receiving PAS (RR=0.52, 95% CI: 0.30-0.91, p=0.02). Conclusions: The beneficial effects of PAS on increasing the penile length and glans width were again confirmed. More gain of penile length was expected in the larger penis at baseline. There are no reported increased postoperative complications in association with PAS.