Background . Advertisement. In addition, interval biometry may be done at whenever required to quantify satisfactory foetal growth. The normal range for the AFI is 5-25 cms. Any single pocket that's over 2 cm is considered adequate.Your doctor will perform an ultrasound to confirm the presence of an excess or lack of amniotic fluid to find out where you rate on the If you have too much fluid, you will likely have an AMNIOTIC FLUID INDEX VALUES (mm) IN NORMAL PREGNANCYModified from Moore TR, Cayle JE: The amniotic fluid index in normal human pregnancy. An AFI of less than 5 to 6 centimeters leads to a condition called oligohydramnios, which means that amniotic levels are low. Only those patients who delivered at 40 weeks were included in the study as we wanted longitudinal data till term. In high risk pregnancies complicated by chronic placental insufficiency liquor is known to drastically reduce in a shorter time and it has been recommended to perform AFI estimation once in three days or at times even frequently depending upon other fetal well-being surveillance tools such as Doppler assessment of fetal circulation. We will be providing unlimited waivers of publication charges for accepted research articles as well as case reports and case series related to COVID-19. However, there is no universal consensus regarding the frequency of AFI estimation in low risk antenatal women. Normal AFI values range from 5 to 25 cm [1, 4]. From 28 to 42 weeks, the amniotic fluid index gradually declined to a mean of 93 mm by 42 weeks' gestation in Table 2.The 50th percentile amniotic fluid index for the preterm patients gestational weeks 28–37 was 130 mm and for the term (38–42 weeks) group was 112 mm. 16 (32%) patients required caesarean delivery for obstetric indication such as failed induction, cephalopelvic disproportion, and fetal distress in labour. Hence, it appears that when the liquor is within normal range, the chances of fetal jeopardy are unlikely to occur within next week; one can safely repeat the AFI after 2 weeks. All 3rd and 97th percentile amniotic fluid index values were within the range of commonly used cutoffs to define oligohydramnios (≤5 cm) and polyhydramnios (≥25 cm). Table Amniotic fluid once thought to be a stagnant pool with approximate turn over time of twenty-four hours. Institutional ethical committee approval was obtained prior to study. There are several methods mentioned in the literature to calculate the effect sizes (Cohen 1988 [From our statistical analysis, we have found that there is no much decrease in AFI at interval of one week, but thereafter the differences become large and significant. Once initial criteria were met, those who were subsequently diagnosed to have abnormalities of liquor volume due to conditions such as hypertensive disorders, gestational diabetes, and placental insufficiency were excluded from the study, so as to obtain normative data. As mentioned in methodology, we have excluded those who delivered before term as we required AFI from 34 weeks to 40 weeks of gestation for analysis purpose.We used difference in mean values of one week to the next week to evaluate the decreasing trend of amniotic fluid from 34 to 40 weeks of gestation (Table Our results indicated that from 34 weeks onwards there is a gradual reduction in AFI. Amniotic fluid volume gradually increases till 32–34 weeks of gestation and thereafter there is a gradual reduction till term [There is wide variation in reference standards for mean AFI values according to population, race, and geography. The final study subjects were 50 low risk pregnant women who underwent serial scans at weekly interval starting from 34 weeks till term.The subjects belonged to the local population consisting mainly of Tuluva, Billava, Bunt, Koraga, Kulala, Devadiga, Konkanis, Shivalli Brahmins, Bayri Muslim, and Catholic communities, the spoken language mainly being Kannada, Tulu, and Konkani. Hence, it is important to determine a critical interval at which the fall in AFI becomes clinically significant.We have not used statistical significance test (involving estimation of Effect size is a simple measure for quantifying the difference between two groups or the same group over time, on a common scale. The mean (standard deviation) birth weight of the neonates (measured in kg) was 2.83 (0.34), with 1st minute APGAR score (mean and standard deviation) of 8.48 (1.09) and 5th minute APGAR was 8.72 (1.01). None of them had any antenatal complications. A polynomial regression analysis of 3rd order was used to find the best fit. Inclusion criteria were low risk singleton pregnancy, starting gestational age of 34 weeks, reliable last menstrual period and dates correlated and confirmed by comparison with first trimester CRL (Crown Rump Length).
Microsoft Excel 2010 was used to plot percentile values (5th, 50th, and 95th) across various gestational ages.
Methods .A prospective and descriptive study was performed, in which an independent sample of 2,868 low‐risk pregnant women were studied using routine ultrasound, including fetal biometry and measurement of AFI.
Amniotic Fluid Index (AFI): this method uses the sum of four of the deepest vertical pocket of fluid. [Accordingly it was estimated that 27 patients are required and we decided to recruit 50 patients to have satisfactory results.Data was analyzed using SPSS version 16 for windows (SPSS Inc., Chicago, IL, USA).