Search results
Results from the WOW.Com Content Network
Amniotic fluid is removed from the mother by an amniocentesis procedure, where a long needle is inserted through the abdomen into the amniotic sac, using ultrasound guidance such that the fetus is not harmed. Amniocentesis is a low risk procedure, with risk of pregnancy loss between 1 in 1,500 – 1 in 700 procedures.
Amniotic fluid index (AFI) is a quantitative estimate of amniotic fluid [1] and an indicator of fetal well-being. It is a separate measurement from the biophysical profile. [1] AFI is the score (expressed in centimetres) given to the amount of amniotic fluid seen on ultrasonography of a pregnant uterus.
The presence of these biophysical variables implies absence of significant central nervous system hypoxemia/acidemia at the time of testing. By comparison, a compromised fetus typically exhibits loss of accelerations of the fetal heart rate (FHR), decreased body movement and breathing, hypotonia, and, less acutely, decreased amniotic fluid volume.
The mean sac diameter [3] can effectively estimate the gestational age [4] between 5 and 6 weeks, with an accuracy of about +/- 5 days. [ 5 ] The yolk sac and embryo should be readily identifiable when the gestational sac reaches a certain size — a yolk sac should be seen when the gestational sac is 20mm and a fetal pole should be seen when ...
Some degree of weight gain is expected during pregnancy. The enlarging uterus, growing fetus, placenta, amniotic fluid, normal increase in body fat, and increase in water retention all contribute weight gain during pregnancy. The amount of weight gain can vary from 5 pounds (2.3 kg) to over 100 pounds (45 kg).
The volume of amniotic fluid typically increases until 36 weeks and starts decreasing after 40 weeks in post-term gestations. [4] For this reason, discrepancies between fundal height measurements and gestational age can be a clinical indication of amniotic fluid abnormality and should be evaluated by ultrasound.
The 1985 maximum power allowed by the U.S. Food and Drug Administration (FDA) of 180 milliwatts per square cm [25] is well under the levels used in therapeutic ultrasound, but still higher than the 30–80 milliwatts per square cm range of the Statison V veterinary LIPUS device.
Amniotic fluid is composed of fetal cells, urine, and lung secretions. [46] 18-20 mL of amniotic fluid is slowly aspirated, with the first 1-2 mL typically discarded due to higher risk of maternal cell contamination. [2] The remaining sample is submitted for laboratory testing. [1]