Effect of maternal feed restriction on prenatal development in rats and rabbits - A review of published data

- Fetal growth is affected by reduced maternal feed intake in rat and rabbit.
- Fetal growth retardation is often accompanied by reduced skeletal ossification.
- Maternal feed restriction does not result in embryo/fetal death or malformation.

With respect to hazard classification for developmental toxicity under the CLP Regulation it is important to consider the possible influence of maternal toxicity. The aim of the present review was to characterize to which extent developmental effects could be caused by non-specific maternal toxicity. Such effects would not be relevant for classification. In prenatal developmental toxicity studies, the administration of high doses is given in the guideline. The associated non-specific systemic toxicity often affects the maternal body weight. Therefore, published results of studies in rats and rabbits, where maternal weight gain during gestation was inhibited by restricted feeding, were examined regarding developmental effects. In summary, maternal feed restriction resulted in a reduction of fetal body weight that was sometimes accompanied by delayed ossification in both species. Considering their magnitude these effects could be interpreted as secondary non-specific (i.e. not caused by a developmental toxicant) effects. Based on the limited number of available publications in total no further consequences on prenatal development by maternal feed restriction were observed.