Critical windows of exposure for children's health: the reproductive system in animals and humans.
Abstract
Drugs and environmental chemicals can adversely affect the reproductive system. Currently,
available data indicate that the consequences of exposure depend on the nature of
the chemical, its target, and the timing of exposure relative to critical windows
in development of the reproductive system. The reproductive system is designed to
produce gametes in far greater excess than would seem to be necessary for the survival
of species. Ten to hundreds of millions of spermatozoa are generated daily by most
adult male mammals, yet very few of these germ cells succeed in transmitting their
genetic material to the next generation. Although the number of oocytes produced in
mammalian females is more limited, and their production occurs only during fetal life,
most ovaries contain several orders of magnitude more oocytes than ever will be fertilized.
Toxicant exposures may affect critical events in the development of the reproductive
system, ranging from early primordial germ cell determination to gonadal differentiation,
gametogenesis, external genitalia, or signaling events regulating sexual behavior.
Although there are differences between the human reproductive system and that of the
usual animal models, such models have been extremely useful in assessing risks for
key human reproductive and developmental processes. The objectives for future studies
should include the elucidation of the specific cellular and molecular targets of known
toxicants; the design of a systematic approach to the identification of reproductive
toxicants; and the development of sensitive, specific, and predictive animal models,
minimally invasive surrogate markers, or in vitro tests to assess reproductive system
function during embryonic, postnatal, and adult life.
Type
Journal articleSubject
Urogenital SystemAnimals
Humans
Disease Models, Animal
Xenobiotics
Risk Assessment
Environmental Exposure
Oogenesis
Spermatogenesis
Embryonic and Fetal Development
Pregnancy
Child Welfare
Adult
Child
Infant, Newborn
Female
Male
Biomarkers
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https://hdl.handle.net/10161/21945Published Version (Please cite this version)
10.1289/ehp.00108s3491Publication Info
Pryor, JL; Hughes, C; Foster, W; Hales, BF; & Robaire, B (2000). Critical windows of exposure for children's health: the reproductive system in animals
and humans. Environmental health perspectives, 108 Suppl 3(SUPPL. 3). pp. 491-503. 10.1289/ehp.00108s3491. Retrieved from https://hdl.handle.net/10161/21945.This is constructed from limited available data and may be imprecise. To cite this
article, please review & use the official citation provided by the journal.
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Show full item recordScholars@Duke
Claude Lebernian Hughes Jr.
Consulting Professor of Obstetrics and Gynecology

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