The Relationship Between Anogenital Distance and Reproductive
Hormone Levels in Adult Men
Michael L. Eisenberg,* Tina K. Jensen, R. Chanc Walters, Niels E. Skakkebaek
and Larry I. Lipshultz†
From the Department of Urology, Stanford University School of Medicine, Palo Alto, California (MLE), Department of Environmental
Medicine, Institute of Public Health, University of Southern Denmark, Winsloewsparken, Odense (TKJ), and University Department of
Growth and Reproduction, Rigshospitalet, Copenhagen (NES), Denmark, and Division of Male Reproductive Medicine and Surgery,
Scott Department of Urology, Baylor College of Medicine, Houston, Texas (RCW, LIL)
Submitted for publication June 3, 2011.
Study received institutional review board ap-
Department of Urology,
Stanford University School of Medicine, 300 Pasteur
Drive, Palo Alto, California 94305 (telephone: 650-
723-4537; FAX: 650-498-5346; e-mail:
† Financial interest and/or other relationship
with Allergan Pharmaceuticals, Auxilium Pharma-
ceuticals, AMS, Pﬁzer and Repros Therapeutics.
Anogenital distance is a marker for endocrine disruption in animal
studies in which decreased distance has been associated with testicular dysfunc-
tion. In this study we investigated whether anogenital distance was associated
with reproductive hormone levels in adult men.
Materials and Methods:
A total of 116 men (mean age 36.1
8.0 years) were
evaluated at an andrology clinic in Houston. Anogenital distance (the distance
from the posterior aspect of the scrotum to the anal verge) and penile length were
measured using digital calipers. Testis size was estimated by physical examina-
tion. Linear regression was used to determine correlations between genital mea-
surements and hormone levels.
Anogenital distance (r
0.03) and penile length (r
0.03) were signiﬁcantly associated with serum testosterone levels while total
testis size was not (r
0.07). No relationship between genital length
and luteinizing hormone, follicle-stimulating hormone or estradiol was identiﬁed.
After adjusting for age the serum testosterone increased by 20.1 ng/dl (95% CI
1.8, 38.4; p
0.03) for each 1 cm increase in anogenital distance. On multivari-
able models no statistically signiﬁcant relationship existed between penile length
and testosterone levels. Moreover men with hypogonadal testosterone levels (less
than 300 ng/dl) had a signiﬁcantly shorter anogenital distance compared to men
with higher testosterone levels (31.6 vs 37.3 mm, p
Anogenital distance may provide a novel metric to assess testicular
function in men. Assuming that anogenital distance at birth predicts adult anogeni-
tal distance, our ﬁndings suggest a fetal origin for adult testicular function.
testosterone, hormones, genitalia, perineum
the last half century there has been
a reported decline in semen quality
and serum testosterone levels with an
increased rate in male genital abnor-
malities and testis cancers.
the phenomenon and etiology are un-
certain, several investigative groups
postulate an environmental factor which
disrupts normal endocrine signaling
leading to abnormal androgen action
and altered genital development.
ing sexual development the immature
genital precursors migrate ventrally
via an androgen mediated pathway.
marker for genital development, the
AGD, has been examined in animals
A sexually dimorphic measure, AGD
was initially used to sex animals.
More recently human studies have
Vol. 187, 594-598, February 2012
THE JOURNAL OF UROLOGY
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