Preimplantation development of the primate embryo after in vitro fertilization.

The developing use of in vitro fertilization (IVF) as a human clinical procedure has prompted the exploitation of nonhuman primates to assess the chromosomal and biochemical normality of embryos produced by IVF. Of 1995 oocytes recovered from squirrel monkeys, 628 (31.5%) matured and 339 (54.0%) fertilized. Fertility can be significantly enhanced by the addition of 1 or 10 microM dbcAMP to the culture medium. Chromosome analysis of oocytes and embryos used in these studies revealed an incidence of abnormality between 7 and 25%, comparable with that found for both in vivo and in vitro fertilized embryos from other laboratory species. There is no evidence that the IVF technique increases chromosomal abnormality. There was a decrease in protein synthesis of oocytes at maturation and during the early embryonic development stages, but an increase in the rate of RNA synthesis as development progressed. There was steroid uptake in early preimplantation embryos. The temporal relationships of early embryonic developmental events in the squirrel monkey have been determined.