Definition - What does Embryonic Stage mean?
The embryonic stage of development refers to the period of time after implantation until the fetal stage begins. This lasts approximately 8 weeks. The embryonic stage is when most of the organs and body structures begin to develop. The embryo is very vulnerable at this stage and problems with maternal nutrition or exposure to environmental toxins can result in deformity or miscarriage.
FertilitySmarts explains Embryonic Stage
There are three major stages of gestation:
- Germinal or Pre-embryonic Stage
- Embryonic Stage
- Fetal Stage
The germinal stage begins when an egg is fertilized by sperm. The embryonic stage begins when the blastocyst implants in the uterine wall. This usually occurs about 6 days after fertilization. The fetal period begins around 8 weeks after fertilization and ends with birth.
After implantation has occurred, the fertilized egg is referred to as an embryo. It will remain an embryo for the next 56 days until the fetal stage begins. The embryonic stage is a period of rapid development. During this time, precursors to almost all of the body organs and structures are formed. This is accomplished by rapid cell division, movement, and differentiation. As a result, this is a very fragile stage of development. Nutritional deficits or toxic exposures in the mother can result in deformities or miscarriage.