In plain words
The amniotic fluid index is a measure of how much fluid surrounds the baby in the womb. An ultrasound checks pockets of fluid in four areas of the belly and adds them up. The result is a number in centimeters. Fluid levels change through pregnancy. A low reading can point to problems with the placenta, the baby's kidneys, or growth. Low fluid is called . Some clinicians now use a single deepest pocket measure instead, which some studies favor. A low reading does not always mean a problem. If you have been told your fluid is low, your provider will decide what checks you need next.
The deeper version
The amniotic fluid index (AFI) sums the deepest vertical pockets in four quadrants of the uterus, a method described by Phelan and colleagues (1987). ACOG Practice Bulletin 145 (2014) on antepartum fetal surveillance defines oligohydramnios by an AFI of 5 cm or less or a single deepest pocket under 2 cm. The Cochrane review by Nabhan and Abdelmoula (2008) found that the single deepest pocket method produces fewer false-positive results, with comparable perinatal outcomes. Low fluid is associated with , renal anomalies, and post-term pregnancy. The controversy concerns the threshold values and whether AFI-guided management improves outcomes relative to deepest pocket methods.
Where it comes up
- Going past your due datePregnancy: Your Body
- Drinking enough waterPregnancy: Eating
- Prenatal tests and ultrasounds: what each one isPregnancy: Your Body
What mothers here say about amniotic fluid index
No one has posted under this term yet.
Sources
- American College of Obstetricians and Gynecologists — Practice Bulletin 146: Antepartum Fetal Surveillance (2014)
- Nabhan AF and Abdelmoula YA, Cochrane Database of Systematic Reviews — Amniotic fluid index versus single deepest pocket measurement (2008)