Inhibin B reference data for fertile and infertile men in Northeast America.
OBJECTIVE
To determine normative levels of inhibin B and examine levels in relationship to FSH, sperm count, and motility in a cohort of fertile and infertile men from the Northeast United States.


METHODS
Prospective comparative study of inhibin B levels in fertile and infertile patient groups.


METHODS
Tertiary academic referral center.


METHODS
Fertile men were recruited among those presenting for elective vasectomy. Men being evaluated for infertility were also recruited within the same practice.


METHODS
Serum collection.


METHODS
FSH and inhibin B levels were measured in serum samples.


RESULTS
A total of 55 fertile and 85 presenting for infertility evaluations were recruited. The mean serum inhibin B level was significantly higher in the fertile (138 pg/mL) than infertile group (78 pg/mL). Inhibin B levels correlated positively (R(2) = 0.27) and FSH correlated negatively (R(2) = 0.33) with total sperm concentration. General linear model multiple regression demonstrated that the FSH and inhibin B were equally predictive of sperm concentration.


CONCLUSIONS
Inhibin B levels in fertile men and infertile men in Northeast America were similar but not identical to those reported in other geographic regions. Both inhibin B and FSH are useful markers of spermatogenesis.
Myers
Gavin M
GM
The Alpert Medical School of Brown University, Providence, Rhode Island, USA.
Lambert-Messerlian
Geralyn M
GM
Sigman
Mark
M
D000328:Adult; D015415:Biomarkers / Q000097:blood*; D002624:Chemistry, Clinical / Q000592:standards*; D005298:Fertility / Q000502:physiology*; D005640:Follicle Stimulating Hormone / Q000097:blood; D006801:Humans; D007248:Infertility, Male / Q000097:blood*; D007265:Inhibins / Q000097:blood*; D016014:Linear Models; D008297:Male; D009511:New England; D011237:Predictive Value of Tests; D012016:Reference Values; D013076:Sperm Count; D013091:Spermatogenesis / Q000502:physiology; D014659:Vasectomy
D015415:Biomarkers; C422364:inhibin B; D007265:Inhibins; D005640:Follicle Stimulating Hormone