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Pregnancy begins when an egg (ovum) is released from your ovary about midway between menstrual periods, and is fertilised by a male cell (sperm). Fertilization usually takes place in the outer end of the Fallopian tube. Millions of sperm surround the ovum, but only one can enter it. As the head of the sperm enters the ovum its tail falls off.

(Click on image to enlarge)

As the fertilized egg moves down the Fallopian tube, it divides into two cells. The cells keep dividing until a solid ball of cells has been formed. When it reaches the womb, this ball of cells becomes attached to the wall of the womb. Once the ball of cells is attached, the tissue surrounding it produces hormones which help the pregnancy to continue.

The ball of cells, which develops into the baby, is referred to as the embryo at this stage. The part of the ball of cells which attaches to the wall of your womb becomes three things – the umbilical cord, the placenta, and the amniotic sac. These are all very important for the growth and protection of the baby.

The changes of pregnancy

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Raising Children Network  Raising Children website is produced with the help of an extensive Australian network including the Australian Government.

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