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Physiology of amniotic fluid volume regulation

Michael G Ross, MD, MPH
Marie H Beall, MD
Section Editor
Charles J Lockwood, MD, MHCM
Deputy Editor
Vanessa A Barss, MD, FACOG


Amniotic fluid (AF) is the liquid that surrounds the fetus after the first few weeks of gestation. During much of pregnancy, AF is derived almost entirely from the fetus and has a number of functions that are essential for normal growth and development [1]:

It helps to protect the fetus from trauma to the maternal abdomen

It cushions the umbilical cord from compression between the fetus and uterus

It has antibacterial properties that provide some protection from infection

It serves as a reservoir of fluid and nutrients for the fetus


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Literature review current through: Jun 2017. | This topic last updated: Jun 02, 2017.
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