RESUMEN
OBJECTIVE: To determine the prevalence and the risk factors associated with intestinal parasitosis in pregnant women and the relation with the newborns. MATERIAL AND METHODS: A transversal analytical study. 207 women were selected and a guided survey was applied. They were also asked for three stool samples for their parasitoscopic study by Faust's method. The levels of hemoglobin as well as the child's birth weight. RESULTS: The prevalence of intestinal parasitosis was 38.2. 84 of the women presented only one parasite. The protozoan Giardia lamblia was very frequent (65.8), followed by Ascaris lumbricoides (13.9). Women with positive samples in the parasitoscopic study were younger (p = 0.002), and a greater probability of a scholastic level lower than Jr. High School, as well as having a dirt floor in their house and a positive contact with domestic animals. The mean weight of the newborn of mothers without intestinal parasitosis was 3,333 +/- 441 g; in the group of mothers with only one parasite was 3,291 +/- 360 g; with two parasites 3,104 +/- 425 g; and three parasites the weight was 2,675 +/- 674 g, these differences were not statistically significant (P = 0.1), however, there is a greater possibility of a newborn with less weight at birth than expected. CONCLUSIONS: The prevalence of intestinal parasitosis in pregnant women is high due to their physiological state. It is necessary to modify some preventive measures of information, education and to give specific treatment before the pregnancy in order to increase some of the pregnant women's health indicators. The newborn of mothers with intestinal parasitosis have a greater probability of being born with less weight than what is expected.