The science of conception

Just in case you blushed instead of paying attention to how babies were made back in school, here’s the baby making low down:

Your Menstrual Cycle
Did you know that your entire stock of ovaries was made in your uterus before you were even born? Baby girls are born with roughly two million eggs, which continue to die until puberty when most women have between 200,000 and 500,000 eggs. Of these only 400-500 mature and are released at a rate of about one a month by your ovaries (ovaries usually ovulate alternatively). The development and release of an egg ready for fertilization by a sperm is called ovulation and this happens in cycles. In the first half of the cycle (roughly 28 days) about 20 eggs begin to ripen. One will mature faster than the others and release itself around 12-14 days before the end of the cycle. The egg grows for 24 hours and produces the hormone progesterone, which is essential for the development of an embryo. If the egg is not fertilized the lining of the uterus (endometrium) is no longer needed, so it sheds and becomes a women’s monthly period.

How babies are made
Astonishingly when a man ejaculates he releases about three and a half millilitres of sperm, and each millilitre contains about 60-150 million sperm. But of about 300 million sperm, only a few hundred will actually reach the egg and of those hundred, only one sperm will manage to penetrate the egg and fertilize it. After ovulation, (remember this happens around 12-14 days before the end of the reproductive cycle) an egg can only be fertilized if it is met and penetrated by a sperm one to two days before ovulation and 24 hours afterwards. This is because sperm cells can live for 2-3 days but an egg only lives for 24 hours unless it is fertilized.

Conception – Fertilization happens when a sperm meets and penetrates an egg. The fertilized egg then divides repeatedly before implanting itself into the lining of the uterus. The pregnancy is now established and the placenta will start to form.

You can work out your ovulation dates over the next 12months by going to gurgle's Ovulation Calculator

Sex
Obviously we cannot forget about sex when talking about the science of conception. Although no statistics are available to show that making love at particular times in the day are better than others, sperm counts are generally higher in the morning. Men also have the strongest sexual urges when they first wake up, so mornings are a good time to try.

Positions to avoid
Avoid straddling your partner or the woman on top position, sitting or standing as these positions cause the semen to leek out and may result in fewer sperm making their way to the egg. Making love in water can cause a change in the vaginal mucus needed for proper sperm passage, and chlorine from swimming pools can create a hostile environment for sperm.

Stress
Baby-making can actually be very stressful especially if you don't fall pregnant as each month goes by. Lots of couples find it a strain to 'feel sexy' when there is so much pressure involved. Although we have suggested some positions that can help with 'baby-making', having sex however you and your partner feel comfortable is always the best idea. Try not to think about it as possibly making a baby and if possible relax. Use our Ovulation calculator to work out which days you are most fertile over the next twelve months. Now all you have to do is book a weekend away so you are both relaxed and have as much sex as you like! You don't have to have more sex then normal (but you can if you want) but make sure you are having regular sex, so every two to three days throughout your cycle, to optimise your chances of falling pregnant.