“Here is the first problem… there is no accurate method for measuring AFV.” The two ultrasound tests aimed at assessing AFV are:
Amniotic Fluid Index: four ‘pockets’ of fluid are measured by ultrasound and added up resulting in an Amniotic Fluid Index (AFI) eg. AFI = 10cm.
Maximum Pool: The ‘single deepest vertical pocket’ of fluid is identified by ultrasound and measured in centimetres.
Neither of these methods are supported by research (that I can find). However, studies comparing the two conclude that the ‘maximum pool’ measurement is the ‘better choice’ (Nebhan & Abdelmoula 2008; Magann et al. 2011). The reasoning for this is interesting… AFI increases the detection of oligohydramnios resulting in increased rates of induction without improving outcomes for babies. So the best method is the one that does not detect the ‘problem’ you are looking for?
Please read the rest of this informative article HERE.