Amniotic fluid index in twin gestation

Abstract

This study was performed to describe a methodology for a two-pocket amniotic fluid index (AFI) for each fetus of a twin gestation. Data included 216 pairs of measurements that were analyzed to yield regressions (curves) for all observations, as well as for the larger and smaller AFI of each observation on a particular set of twins. The twin AFI increased non-linearly until week 27. From week 27 to week 36, decreasing linear trends were found. Measures of intrasonographer, intersonographer, within-mother and between-mothers variation are reported. The estimates of variation were used to plot confidence limits for all three curves.

Twin pregnancy: the role of ultrasound in management

“…The first sign is a marked discordance in amniotic fluid volume in MC twins (79,80). An estimation of amniotic fluid volume is therefore used to assess the well being of both twins.…”

A Systematic Review of Amniotic Fluid Assessments in Twin Pregnancies

“…16 Two of the 3 studies that accounted for the dividing membrane in the AFV measurement reported a nonlinear correlation between the AFI and GA, with a peak AFI measured at 26 to 28 weeks' gestation and then declining linearly until delivery ( Figure 2B). 30,36 In contrast to these studies, Magann et al 29 reported no correlation between GA and AFV using dye dilution techniques in a longitudinal study of 45 sets of diamniotic twins from 27 to 38 weeks' gestation (r = 0.134; P = .404; Figure 2B). However, the patients in that study were enrolled between 27 and 38 weeks' gestation.…”