The Full Wiki

Amniotic fluid: Wikis

Advertisements
  
  

Note: Many of our articles have direct quotes from sources you can cite, within the Wikipedia article! This article doesn't yet, but we're working on it! See more info or our list of citable articles.

Encyclopedia

From Wikipedia, the free encyclopedia

Amniotic fluid or liquor amnii is the nourishing and protecting liquid contained by the amniotic sac of a pregnant woman. The amniotic sac grows and begins to fill, mainly with water, around two weeks after fertilization. After a further 10 weeks the liquid contains proteins, carbohydrates, lipids and phospholipids, urea and electrolytes, all of which aid in the growth of the fetus. In the late stages of gestation much of the amniotic fluid consists of fetal urine.

The amniotic fluid increases in volume as the fetus grows. The amount of amniotic fluid is greatest at about 34 weeks after conception or 34 weeks ga (gestational age). At 34 weeks ga, the amount of amniotic fluid is about 800 ml. This amount reduces to about 600 ml at 40 weeks ga when the baby is born.

Amniotic fluid is continually being swallowed and "inhaled" and replaced through being "exhaled", as well as being urinated by the fetus. It is essential that the amniotic fluid be breathed into the lungs by the fetus in order for the lungs to develop normally. Swallowed amniotic fluid contributes to the formation of meconium.

Analysis of amniotic fluid, drawn out of the mother's abdomen in an amniocentesis procedure, can reveal many aspects of the baby's genetic health. This is because the fluid also contains fetal cells which can be examined for genetic defects and amniotic stem cells.

Amniotic fluid also protects the developing baby by cushioning against blows to the mother's abdomen, allows for easier fetal movement, promotes muscular/skeletal development, and helps protect the fetus from heat loss.

The forewaters are released when the amnion ruptures, commonly known as when a woman's "water breaks". When this occurs during labour at term, it is known as "spontaneous rupture of membranes" (SROM). If the rupture precedes labour at term, however, it is referred to as "premature rupture of membranes" (PROM). The majority of the hindwaters remain inside the womb until the baby is born.[1]

Contents

Amniotic fluid and stem cells

Recent studies discovered that amniotic fluid contains a considerable quantity of stem cells[2], multipotent and able to differentiate into various tissues, useful for future human application.[3][4][5]. Some researchers as Anthony Atala of Wake Forest University and a team from Harvard University and Italian Paolo de Coppi have found that amniotic fluid is also a plentiful source of non-embryonic stem cells.[6] These cells have demonstrated the ability to differentiate into a number of different cell-types, including brain, liver and bone. These stem cells are also called amniotic stem cell.[7][8]

It is possible to conserve the stem cells extracted from amniotic fluid in a private stem cells banks: the first in Us - Biocell Center - is located in Boston, Ma [7] [8] [9].

Complications related to amniotic fluid

Too little amniotic fluid (Oligohydramnios) or too much (Polyhydramnios or Hydramnios) can be a cause or an indicator of problems for the mother and baby. In both cases the majority of pregnancies proceed normally and the baby is born healthy, but this isn't always the case. Babies with too little amniotic fluid can develop contractures of the limbs, clubbing of the feet and hands, and also develop a life threatening condition called hypoplastic lungs. If a baby is born with hypoplastic lungs, which are small underdeveloped lungs, this condition is potentially fatal and the baby can die shortly after birth.

On every prenatal visit, the obstetrician/gynaecologist or midwife should measure the patient's fundal height with a tape measure. It is important that the fundal height be measured and properly recorded to ensure proper fetal growth and the increasing development of amniotic fluid. The obstetrician/gynaecologist should also routinely ultrasound the patient—this procedure will also give an indication of proper fetal growth and amniotic fluid development. Oligohydramnios can be caused by infection, kidney dysfunction or malformation (since much of the late amniotic fluid volume is urine), procedures such as chorionic villus sampling (CVS), and preterm premature rupture of membranes (PPROM).

Oligohydramnios can sometimes be treated with bed rest, oral and intravenous hydration, antibiotics, steroids, and amnioinfusion.It is also important to keep the baby warm.

Polyhydramnios is a predisposing risk factor for cord prolapse and is sometimes a side effect of a macrosomic pregnancy. Hydramnios is associated with esophageal atresia. Amniotic fluid is primarily produced by the mother until 16 weeks of gestation.

Preterm premature rupture of membranes (PPROM) is a condition where the amniotic sac leaks fluid before 38 weeks of gestation. This can be caused by a bacterial infection or by a defect in the structure of the amniotic sac, uterus, or cervix. In some cases, the leak can spontaneously heal, but in most cases of PPROM, labor begins within 48 hours of membrane rupture. When this occurs, it is necessary that the mother receive treatment to avoid possible infection in the newborn.

Color of the amniotic fluid, with possible meanings:

See also

References

  1. ^ Forewaters and hindwaters in Q&A section at babyworld.co.uk
  2. ^ "Stem cells in amniotic fluid show promise", Los Angeles Times, Jan 8 2007, retrieved 27 July 2009[1]
  3. ^ "Amniotic Fluid Yields New Type of Stem Cell", PBS - The Online News Hour, Jan 8 2007, retrieved 27 July 2009[2]
  4. ^ "Versatile Stem Cell Identified in Amniotic Fluid", Pamela J. Hines, International Society of Stem Cell Research, March 21, 2008, retrieve 27 July 2009[3]
  5. ^ "Amniotic Stem Cells - File:Moz-screenshot-4.jpgMesenchimal Stem Cells in Human Application", Biocell Center Group, 2009, retrieved 27 July 2009[4]
  6. ^ "Isolation of amniotic stem cell lines with potential for therapy : Abstract : Nature Biotechnology". http://www.nature.com/nbt/journal/v25/n1/abs/nbt1274.html. Retrieved 2007-10-13. 
  7. ^ "Isolation of amniotic stem cell lines with potential for therapy", Nature Biotechnology 25, 100 - 106 (2007), Published online: 7 January 2007 | doi:10.1038/nbt1274, retrieved 27 July 2009[5]
  8. ^ "Scientists See Potential In Amniotic Stem Cells", Washington Post, Jan 8 2007, retrieved 27 July 2009[6]
Advertisements

Advertisements






Got something to say? Make a comment.
Your name
Your email address
Message