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Updated: Jul 19, 2026
03:28
Sperm Collection of Differential Quality Using Density Gradient Centrifugation
Published on: November 29, 2018
Sex-sorted sperm and fertility: an alternative view
Valerie J Grant1, Lawrence W Chamley
1Department of Psychological Medicine, Faculty of Medical and Health Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand. vj.grant@auckland.ac.nz
Biology of Reproduction
|October 27, 2006
Summary
Mammalian females may influence offspring sex before conception, potentially explaining lower fertility rates with sex-sorted sperm. This challenges traditional chance-based sex determination theories.
Area of Science:
- Reproductive Biology
- Evolutionary Biology
- Mammalian Reproduction
Background:
- Current sperm sorting technologies efficiently separate X and Y chromosome-bearing sperm.
- However, overall fertility rates using sex-sorted sperm remain suboptimal despite improvement efforts.
Purpose of the Study:
- To explore potential biological factors influencing sex determination in mammals.
- To investigate if female preconceptual control over offspring sex could explain inefficiencies in sex-sorted sperm fertility.
Main Methods:
- Review of evolutionary biology and sex allocation theory.
- Analysis of existing data on sex-sorted sperm fertility rates.
- Theoretical modeling based on potential female influence on sex determination.
Main Results:
- Sex allocation theory suggests a potential modification to the chance theory of mammalian sex determination.
- Evidence indicates that mammalian females might exert preconceptual influence on the sex of their offspring.
Conclusions:
- Female preconceptual control over offspring sex could partially account for suboptimal fertility observed with sex-sorted sperm.
- This challenges the purely random model of sex determination in mammals and opens new research avenues.
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