Making your baby

A crowd of 300 million dashes in the dark at top speed to capture a rare and mysterious prize. Hundreds of millions will perish before they come close, but one will be victorious. It may sound like a big-budget blockbuster, but it's the real-life drama that makes a baby! When you were a 20-week-old foetus inside your own mother's womb, you already had all of the eggs you will ever have, about 400,000 in all. Of these, only about 400 are destined to mature and be released over the course of your reproductive life. Even fewer will ever be fertilised. And only about 40 percent of those that are fertilised will implant in the lining of your uterus and grow into an embryo.

Of those implanted embryos, only 80 percent will grow into a full-term baby. In other words, the cells that came together to create your baby are luckier than a lottery winner. Conditions must be perfect and the timing must be exactly right for conception to happen in the first place.

Your progress

Ovulating

Eggs, or ova, are the largest cell in the human body, measuring about 1/175th of an inch or 1/7th of a millimetre. Your eggs have been waiting for years inside a tiny bubble in your ovary called a follicle. Every month, about three to 20 eggs receive a hormonal signal that cues them to mature and prepare for ovulation. As ovulation nears, one follicle will become dominant and grow faster than the others, nearly tripling in size, and the others will stop growing.

As the follicle grows, it sends a hormonal signal to the lining of your uterus, called the endometrium, telling it to thicken with blood. Ovulation happens when the winning egg bursts through the follicle and through the wall of your ovary.

Some women experience sharp pains on one side when the egg bursts through the ovary wall, others don't feel anything. The egg then starts to travel down the fallopian tube, coaxed by tiny finger-like projections called fibrae.

What to think about

Your partner's sperm count is key to making conception happen. While technically it only takes one sperm to fertilise an egg, sperm swim and work in teams. Alcohol, hot baths, tight pants and exposure to certain drugs and chemicals can be fatal to sperm. Therefore if you are trying to conceive, it’s well worth encouraging your partner to adopt a healthy lifestyle.