RESUMEN
The essential oil of Rosmarinus officinalis L. (EORO) is used in cosmetics, in the food industry and in medicines, presenting antimicrobial and antifungal activity. Aim of the study: to observe maternal toxicity and embryo development after treatment of dams with EORO. Inseminated rats were distributed in four groups (n =15): Control (C) (saline 0.5ml) and treated with 242 (T1), 484 (T2) and 968mg/Kg (T3) of EORO, from the fifth to the seventh dpc and sacrificed on the 15th dpc. Variables analyzed: maternal behavior, body weight gain, food consumption, kidneys, liver and ovaries weight, hemogram, number of corpora lutea, implants, live, dead, malformed fetuses and placenta and fetuses weight. Statistics: Dunnett and Chi-square tests (α=0.05). The EORO higher dose reduced (p<0.05) maternal number of erythrocytes; the haematocrit, hemoglobin concentration and the fetuses body weight. Conclusions: Highest dose of EORO reduce the fetuse´s body weight and induced anemia in the dams.