Physiology of amniotic fluid volume regulation
- Michael G Ross, MD, MPH
Michael G Ross, MD, MPH
- Distinguished Professor of Obstetrics and Gynecology
- David Geffen School of Medicine at UCLA
- Marie H Beall, MD
Marie H Beall, MD
- Clinical Professor of Obstetrics and Gynecology
- Geffen School of Medicine at University of California, Los Angeles
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 :
●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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- SOURCES OF AMNIOTIC FLUID
- Early gestation
- - Coelomic fluid
- - Amniotic fluid
- Mid gestation
- Late gestation
- - Fetal urination
- - Fetal lung secretions
- - Fetal swallowing
- - Intramembranous flow
- - Oral-nasal secretions and transmembranous flow
- AMNIOTIC FLUID OSMOLALITY, SODIUM, AND CHLORIDE
- REGULATION OF AMNIOTIC FLUID VOLUME
- NORMAL AMNIOTIC FLUID VOLUME ACROSS GESTATION
- SUMMARY AND RECOMMENDATIONS