J Urol. 2024 Apr 11:101097JU0000000000003957. doi: 10.1097/JU.0000000000003957. Online ahead of print.
ABSTRACT
PURPOSE: To characterize the distribution of follicle stimulating hormone (FSH) in fertile and subfertile non-azoospermic men, and to determine the ability of various FSH thresholds to predict fertility status.
MATERIALS AND METHODS: We performed a retrospective cohort study of 1389 non-azoospermic men who presented for fertility evaluation. Men with at least 2 semen analyses (SA) and one FSH level were included. Men were dichotomized into fertile and subfertile groups based on total motile sperm count (TMSC). FSH was evaluated within a multivariable model, and positive predictive values (PPVs) for subfertility were used to assess the clinical utility of various FSH thresholds.
RESULTS: One thousand fifteen (80%) men were classified as fertile and 274 (20%) as subfertile. Age, presence of varicocele, and testosterone levels were not statistically different between the groups. Median FSH was 4.0 vs 6.0 (P < .001) among fertile vs subfertile men. Multiple FSH thresholds ranging from 2.9 to 9.3 performed similarly in predicting fertility status (PPV 0.49-0.59). Only FSH thresholds above the 95th percentile (12.1) had PPVs greater than 0.7. The highest PPV (0.84) was seen at an FSH of 20.8 (99th percentile).
CONCLUSIONS: While there were significant differences in FSH levels among fertile and subfertile non-azoospermic men, multiple FSH cutoffs between 2.2 and 9.3 performed poorly for prediction of fertility status as determined by TMSC. It was not until the 95th percentile FSH value that a clinically useful level of predictability for subfertility was reached, indicating that FSH should not be used as a standalone test of fertility status. Nonetheless, FSH testing remains clinically useful and may be most informative in the setting of extreme values or discordant FSH and SA results.
PMID:38603647 | DOI:10.1097/JU.0000000000003957
