[Toxic action of morphocycline on pregnant rats]

Morphocycline was administered intravenously to rats of Wistar line in doses of 100, 50 and 20 mg/kg at various periods of pregnancy. It was found that a single administration of morphocycline in the above doses to the rats on the 9th day of their pregnancy resulted in abortus in some female rats. Death and resorption of the fetus were more frequent after the antibiotic use in doses of 20 and 50 mg/kg. Repeated administrations of morphocycline in doses of 20 mg/kg resulted in abortus and postimplantation death of the fetus most pronounced in the animal groups treated with the antibiotic during the periods of the 7th to the 10th and from the 11th to the 14th days of pregnancy. The teratogenic activity of morphocycline was slightly pronounced. It was observed in some fetus after both single and repeated administrations of the antibiotic.