Presentation on theme: "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."— Presentation transcript:
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.
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