Waist to Hip Ratio Index as Anthropometric Indicator of Obesity among Pregnant Women in Port Harcourt, Nigeria

There have been controversies on defined anthropometric indices for the assessment of obesity in pregnant women as certain cut-off values relating to it are influenced by age, sex, ethnicity and trimesters of pregnancy. This study is aimed at investigating the use of anthropometric indices particularly waist to hip ratio to measure obesity and determine its prevalence in the different trimesters of pregnancy. The research is a prospective study of 460 pregnant women in the sample proportion of 110, 110, 240 in the 1st, 2nd, 3rd trimesters respectively chosen randomly from antenatal clinic of the Rivers State Primary Health care centre, Rumuepirikom, Port Harcourt, Nigeria. Measurements of height, weight, hip circumference (HP) were obtained. Basal metabolic index (BMI) was calculated from values of height and weight. Waist to hip ratio (WHR) was also calculated from waist and hip values. The result showed a BMI prevalence of 3.6%, 7.3% and 0.8%; WHR prevalence of 43.6%, 35.5% and 14.2% in the 1st, 2nd and 3rd trimesters respectively. A negative linear correlation was shown between the index and BMI as an independent variable in first trimester with value (r=-0.015). Generally, the study provides a high prevalence of WHR relation to WHO values as well as establishing 1st trimester as a good indicator of obesity in pregnant women in the population studied.

Key Words: Body Mass Index, Waist-to-Hip Ratio, Trimesters, Waist circumference, Hip circumference, Obesity.