Curve of fundal height measurements according to gestation age among low-risk pregnant women - Revista Brasileira de Ginecologia e Obstetrícia

PURPOSE: to build a curve of fundal height according to gestational age among low-risk pregnant women and to compare it with the official standards used in Brazil. METHODS: a prospective observational study was carried out. A sample of 227 low-risk pregnant women with gestational age from 13 to 39 weeks was followed-up in the prenatal care sector of two public health services from João Pessoa, PB. Women with a known gestational age, a single live fetus, without malformation, with no known maternal-fetal pathological condition that could possibly affect fetal growth, with a normal body weight, and non-smokers were included in the study. Their fundal height was measured in a standard way, after a previous ultrasound done to confirm the gestational age. The same investigator performed 1206 measurements and each woman had a mean of 5.3 measurements. Statistical tests were performed with a significance level of 5%. Tables and graphs of fundal height were built according to the gestational age with the 10th, 50th and 90th percentiles. RESULTS: the values of percentiles 10, 50 and 90 of fundal height in each gestational age allowed the construction of a pattern curve of fundal height by gestational age among low-risk pregnant women. A clear visual difference was observed between this new and the official fundal height curve. Statistical analyses showed significant differences between them from the 19th week on. CONCLUSION: the results suggest different normal fundal height and fetal growth patterns among low-risk pregnant women on prenatal assistance compared to the used standard curve, thus with different performances when used for diagnosing fetal growth deviations. Future studies should validate the current fundal height curve by gestational age in order to possibly use it as a reference pattern.