ABSTRACT
Reproductive and developmental toxicity experiments are conducted in laboratory animals for the evaluation of potential adverse effects of chemical compounds on fertility, reproduction, and fetal development. Regulatory agencies in the United States routinely require such experi ments for approval of drugs, pesticides, or food additives. A test com pound is administered to either parent before conception, during prena tal development, or postnatally. A typical reproductive or developmental study involves one control and two to four dose groups of 20-30 (preg nant) animals, usually rats, mice, or rabbits. The highest dose is chosen to produce minimal maternal toxicity, ranging from marginal body weight reduction to not more than 10% mortality (Environmental Pro tection Agency [EPA], 1991). The pregnant dams normally are humanely killed just before term, and the uterine contents are then examined to study reproductive and developmental toxicity of the test compound. The experimental outcomes for each female typically include numbers of corpora lutea, implantation sites, dead or resorbed implants, individ-
ual malformation of viable fetuses, normal fetuses, fetal weight, fetal lengths, and such.
