Agwu Emeka John, Ugwu Anthony C, Shem Samuel L, Abba Muhammed
Radiology Unit, New Hope Hospital, Onitsha Anambra State, Nigeria.
Department of Radiography and Radiological Sciences, Faculty of Health Sciences and Technology, Nnamdi Azikiwe University Nnewi Campus, Nigeria.
Acta Radiol Open. 2016 Aug 12;5(8):2058460116652651. doi: 10.1177/2058460116652651. eCollection 2016 Aug.
Amniotic fluid (AF) is one of the major determinants of fetal biophysical profile and can predict pregnancy outcome. Abnormal value of amniotic fluid index (AFI) may indicate fetal and maternal disorders.
To establish reference standards for AFI for this population after 28 weeks of pregnancy and evaluate the relationship between AFI, the estimated fetal weight (EFWT), and fetal gender.
A prospective cross-sectional estimation of AFI and FWT was done in 385 apparently healthy pregnant women in the gestational age range of 28-42 weeks. General scanning in longitudinal, transverse, and oblique directions of the abdomen was done to assess the fetal wellbeing and determine the fetal gender for each participant. AF was measured in each of the quadrants of the abdomen. The four values of the AF were summed to get the AFI. Measurement of the head circumference, biparietal diameter, abdominal circumference, and femoral length of the fetus were obtained. The EFWT was calculated using Hadlock's formula. The data were divided into five groups: 28-30 weeks 6 days; 31-33 weeks 6 days; 34-36 weeks 6 days; 37-39 weeks 6 days; and 40-42 weeks. AFI for the different gestational age group studied and their percentiles were obtained.
AFI normogram for the local population was established. Positive and significant correlations of AF and EFWT were seen in all the gestational age groups of the women. No significant correlations between AF and EFWT was seen in male fetuses. Regression equations of EFWT and AFI were obtained for female fetuses.
The normal range for AFI values for the third trimester was established and could be used to evaluate AFI in the studied population. Established fetal weight should be taken into account when interpreting AFI for female fetuses but this need not be applied for male fetuses.
羊水（AF）是胎儿生物物理评分的主要决定因素之一，可预测妊娠结局。羊水指数（AFI）异常值可能提示胎儿和母亲疾病。
建立该人群妊娠28周后AFI的参考标准，并评估AFI、估计胎儿体重（EFWT）和胎儿性别的关系。
对385名孕龄在28 - 42周的健康孕妇进行AFI和FWT的前瞻性横断面评估。对腹部进行纵、横、斜方向的常规扫描，以评估胎儿健康状况并确定每位参与者的胎儿性别。在腹部的每个象限测量羊水。将四个象限的羊水值相加得到AFI。测量胎儿的头围、双顶径、腹围和股骨长度。使用哈德洛克公式计算EFWT。数据分为五组：28 - 30周6天；31 - 33周6天；34 - 36周6天；37 - 39周6天；以及40 - 42周。获得所研究不同孕周组的AFI及其百分位数。
建立了当地人群的AFI标准曲线。在所有孕周组的女性中，羊水与EFWT呈正相关且具有统计学意义。在男性胎儿中，未发现羊水与EFWT之间存在显著相关性。获得了女性胎儿EFWT和AFI的回归方程。
确定了孕晚期AFI值的正常范围，可用于评估所研究人群的AFI。在解释女性胎儿的AFI时应考虑既定的胎儿体重，但这不适用于男性胎儿。
