But if it involves asphyxiation it is not recommended for the cautious, with numerous fatalities recorded, including the actor David Carradine, singer Michael Hutchence and a UK Member of Parliament. Let us start, as most of us did, with simple, unprotected sex between a man and a woman, and ask: The moral of all this is, possibly, that sex can be just as much about risk as morality. There are several solutions available and they are very effective. Ovulation usually happens midway between the first-day of 2 consecutive periods, but this can vary from the eight day to the twentieth day of a day cycle. This would be the first day or day one of your menstrual period. Researchers calculate the average risk at varying times in a monthly cycle of a woman, but you should know that your risk can be lower or higher. Unfortunate end Finally, we should never forget the risks of such an energetic pursuit. Last year, researchers estimated that 1 in 45 heart attacks are triggered by sexual activity. This is in staggering contrast to countries such as Korea, Japan, Switzerland, the Netherlands and Sweden, which all have birth rates of fewer than seven per 1, teenagers. Check out our Frequently Asked Questions page. People who study how populations change are called demographers, and they use the rather academic term to describe the chances of becoming pregnant during one menstrual cycle: And that means we can begin to look for juicy numbers to find out just how risky things are in the bedroom. Pregnancy usually occurs around the ovulation period, the time when your ovary releases egg in the fallopian tube. Do you have a question about your period, ovulation, pregnancy or other related topic? Calculating success So, given this, what are the chances of success for an average couple trying to have a child? However, this missed or late period is not a sure sign as there are many other things that can cause it besides pregnancy.