INTRODUCTION: Pre-pregnancy overweight and obesity have been proposed as risk factor to diabetes and hypertension during pregnancy. These medical complications enhance the economic burden related to attend the pregnancy when it is classified as high risk pregnancy. OBJECTIVES: Identify diseases related to pre-gestational overweight and obesity in women with high risk pregnancy and estimate the economic burden to attend high risk pregnancy compared with normal pregnancy METHODS: Were studied 600 patients with high risk pregnancy to identify pre-pregnancy overweight and obesity and were estimated the cost related to the medical health care during pregnancy. Were calculated: mean, standard deviation, median, percentilar values, logistic regression and Odds Ratio with 95% confidence interval. Were estimated costs for a hypothetical group of 600 women with normal pregnancy, using Monte Carlo simulation method to compare economic burden between high risk pregnancy and normal pregnancy. Statistical differences were calculated with Student T test to paired samples. Groups were paired by maternal age and gestational age. RESULTS: Pre-pregnancy body mass index mean was 29.59 (±6.42)kg/m2. The obesity was a risk factor to develop gestational diabetes (OR: 1.95; IC95%: 1.39 to 2.76; p=0.000). Were estimated in USD, to following costs: mean cost for prenatal health care: [$165.28 (±$52.39) in normal pregnancy; $801.18 (±$272.14), for high risk pregnancy, p=0.000], mean cost for laboratory test [$ 138.41 (±$32.12) normal pregnancy; $895.91 (±$304.32) high risk pregnancy (p=0.000)], delivery cost [$748.39 (±$340.51) normal pregnancy; $1,762.60 (±$513.88), p=0.000 high risk pregnacy] and mean total cost $2,514.86 (±$852.57), in normal pregnancy and $6,800.34 (±$3,829.82) high risk pregnancy (p=0.000). CONCLUSIONS: