STAGES OF PRENATAL DEVELOPMENT PRENATAL The term prenatal

STAGES OF PRENATAL DEVELOPMENT

PRENATAL • The term prenatal means the period of time before delivery. • Today we are going to talk about the prenatal development of the baby in utero (in the uterus).

Period One: the Zygote • Period One is the ZYGOTE stage which lasts from fertilization to two weeks. • The fertilized egg reaches the uterus or womb where it attached to the lining of the uterine wall. • The main activity in this stage is cell division. • At the end of this period the baby is the size of a pin head.

Period two: the Embryo • The EMBRYO becomes fully attached to the uterine lining. • The placenta forms between the uterus and the embryo. • Nourishment and oxygen are carried to the embryo by the umbilical cord which is filled blood. • Any wastes or toxins are also eliminated through the cord. • The embryo is surrounded by amniotic fluid. • This period lasts 2 -8 weeks.

Period three: the Fetus • A human baby can be recognized (arms, legs and internal organs have developed. • At 5 months there is movement. • The baby begins to curl into the “fetal position”. • At 7 months the baby can live outside the womb. • At the beginning of the 9 th month the fetus moves into the birth position by lowering into the birth canal. • This period lasts from 8 weeks to Birth.

Pregnancy • Pregnancy lasts 40 weeks full term.

Miscarriages • Most likely to happen in the first three months. • Reasons that a miscarriage might happen: – Deformed egg – Placenta failure – the fetus does not get enough oxygen – Weak cervix – Trauma to the mother or child – accident, breathing in poisonous chemicals – Age (over 35) – History of miscarriages – Trouble getting pregnant