This is the direct translation, which may work here.

This is what it means according to Wikipedia:

Downward harmonization is an econo-political term describing the act of adapting the trade laws of a country with an established economy "downward" to the trade laws of the country with a developing economy. This "harmonizing" may affect labor laws, human rights laws, minimum-wage, industry standarads, quality control, anti-terrorism, etc.

http://en.wikipedia.org/wiki/Downward_harmonization

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Note added at 2 hrs (2007-07-24 12:05:36 GMT)
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I read your paragraph like this:

Así, algunos autores consideran que la equidad en el mercado laboral, que produce una armonización hacia abajo, no existe, ya que las mujeres ocupan los empleos peor retribuidos, más inseguros, y con peores expectativas profesionales