The prenatal period has some important characteristics, each of which has a long-lasting effect on development during the lifespan.

This is the most important and first period of development in the life span.

It is the first but shortest period for the newborn baby or infancy, which starts from conception and ends at the birth time of the baby. This period is approximately 270 to 280 days or nine months of a calendar.

Heredity factors are also important for prenatal development; it serves as the
foundation for later development. While favourable or unfavourable conditions both before and after birth may and probably will affect to some extent the physical and psychological traits that make up this heredity endowment. The changes will be quantitative and not qualitative.

Favourable and unfavourable conditions of the mother‘s body can foster the
development of hereditary potential. Sometimes the hereditary potentials are so influenced by environmental conditions that they affect the embryo or the fetus as the case may be affecting the development adversely.

At the time of conception, the sex of the baby is fixed. Except when surgery is used for sex transformation, the sex of the individual, determined at the time of conception, remains the same and does not change.

During the prenatal period, proportionally greater growth and development take place than at any other time throughout the entire life of humans.

Before birth (during nine months) the child grows from a microscopically small cell to an infant who measures approximately twenty inches in length and weight, on average 7 pounds. It is observed that during this time weight increases 11 million times.

Many believe that this time is more hazardous than other periods of the lifespan. It certainly is a time when environmental or psychological hazards can have a marked effect on the pattern of later development.

During the prenatal period, the attitudes of people towards the newly created
individual have a significant impact on the development. For example, the mother’s positive attitude is essential to the normal development of the newly created individual.