The Process of Human Fertilization

A baby begins life as a fertilized egg, formed by the union of dad's sperm and mom's egg.

Conception and birth are miracles. We are all fearfully and wonderfully made, non of us an accident.

The Story of Creation Within Your Womb

The story begins at ovulation, when your ovary releases a minute egg into one of your fallopian tubes.

At about the same time, your spouse ejaculated his semen, containing million of sperm, high into your vagina. He can deposit about 100 miliion sperm at any one ejaculation.

The sperm have the daunting task of penetrating your cervical mucus, swimming through your cervix, through your womb into your fallopian tube to meet your egg, that is, if you have released one.

His sperm is able to swim up in a liquid made by his seminal vesicles and prostate gland. The chemicals in this liquid make the sperm tails beat, propelling them along your fallopian tubes.

Sperm is able to move at a rate of about 3mm a minute. However, some sperm may reach your fallopian tubes in as little as five minutes. Others may take hours to reach there.

Of the millions of sperm that are deposited, only a few thousands manage to reach the area near the end of each fallopian tube. Of these few thousands of sperm, only a mere hundred or so actually reach your egg. And of those that eventually reach your egg, only one will fertilize it.

By the way, fertilization, if it happens, usually occurs in your fallopian tube.

Ok, back to the story.

The sperm that eventually reach your egg will try to penetrate it by releasing an enzyme to break down and disperse the outer follicle cells of your egg. This is not a job for the faint hearted.

You see, the surface of your newly released egg is covered with two layers of cells. Any sperm that aspire to fertilize your egg must pass through both layers of cells. No individual sperm will be able to break down the layers of cells alone. This job requires team work.

So how do they 'break into' your egg?

All the sperm that reach your egg will release their enzyme together to scatter the outer cells of your egg. As they keep at it, the outer cells will slowly give way, until one lucky sperm is be able to find a weak spot and penetrate it!

Mission accomplished!

Upon its successful penetration, your egg will set off an instant biochemical change in its coating to prevent another sperm from penetrating it. The remaining sperm which do not get to fertilize your egg will die eventually.

The miracle of a new life unfolds.

The nucleus of his sperm fuses with the nucleus of your egg, uniting both your genetic materials together to form a brand new individual.

About thirty hours after the fusion of cells, your fertilized egg will start cell division within itself. It will divide into two cells, then into four, then eight, and so forth. Within a matter of a few weeks, billions of cells will form an embryo.

Even as your fertilized egg is developing and growing, it continues to move along your fallopian tube until it reaches your womb after 5 to 7 days. There, it will implant itself into the wall of your womb and slowly grow into a lovely baby over the next thirty-eight weeks.

Ah, there you have it. A successful pregnancy, the process of human fertilization.

Aren't you awed by this process of creation within your body?

Artificial Ferilization

Knowing these basic facts on procreation, scientists are able to help infertile couples conceive through in vitro fertilization, that is uniting sperms and eggs in vitro, that is, in an artificial environment outside the mother's body.

Sometimes, a few eggs will be fertilized at the same time. One fertilized egg will be chosen to be implanted into the mother's womb.

Though babies conceived thus are usually called test-tube babies, they are certainly no artificial human beings. It is the process of fertilization that is artificially achieved. The scientists still have to work with God-made human sperm and eggs to aid infertile couples bear babies.

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