Pregnancy hormones: Both men and women have hormones, which are chemicals that circulate in the bloodstream. They carry messages to different parts of the body and result in certain changes taking place. Female hormones, which include estrogen and progesterone, control many of the events of a woman’s monthly cycle, such as the release of eggs from her ovaries and the thickening of her uterus lining.
During pregnancy, your hormone levels change. As soon as you have conceived, the amount of estrogen and progesterone in your blood increases. This causes the uterus lining to build up, the blood supply to your uterus and breasts to increase and the muscles of your uterus to relax to make room for the growing baby.
The increase in hormone levels can affect how you feel. You may have mood swings, feel tearful or be easily irritated. For a while you may feel that you cannot control your emotions, but these symptoms should ease after the first three months of your pregnancy.
Getting pregnant with a boy or girl?
Every normal human cell contains 46 chromosomes, except for male sperm and female eggs. These contain 23 chromosomes each. When a sperm fertilizes an egg, the 23 chromosomes from the father pair with the 23 from the mother, making 46 in all.
Chromosomes are tiny, thread-like structures which each carry about 2,000 genes. Genes determine a baby’s inherited characteristics, such as hair and eye color, blood group, height and build. A fertilized egg contains one gender chromosome from its mother and one from its father. The gender chromosome from the mother’s egg is always the same and is known as the X chromosome.
But the gender chromosome from the father’s sperm can be an X or a Y chromosome.
If the egg is fertilized by a sperm containing an X chromosome, the baby will be a girl (XX). If the sperm contains a Y chromosome, the baby will be a boy (XY).
Sperm is about 1/25th of a millimeter long and has a head, neck and tail.
The tail moves from side to side so that the sperm can swim up the cervix into the uterus and fallopian tubes.
One egg or ovum (occasionally two or more) is released from the woman’s ovaries every month. It moves down into the fallopian tube where it may be fertilized by a man’s sperm.
The best time to get pregnant
You are most likely to get pregnant if the egg is fertilized within a day or so of ovulation. This is usually about 14 days after the first day of your last period.
An egg lives for about 12–24 hours after it is released. For you to get pregnant, the egg must be fertilized by a sperm within this time. Sperm can live for up to seven days inside a woman’s body. So during seven days before ovulation, the sperm will have had time to travel up the fallopian tubes to ‘wait’ for the egg to be released.
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