Until they decide the time is right to start a family, most women will have spent the entire span of their reproductive lives trying their hardest to avoid conception, and for the majority that means using a contraceptive. We have been warned so often that it can ‘only take one time’ of unprotected sex to become pregnant and we’ve worried so much about how easy it is to become pregnant that when you want to have a baby it can come as something of a surprise to find that you can stop using contraception and not get pregnant in a couple of months.
When are you fertile?
The egg released by one of your ovaries each month at ovulation will only live for a maximum of twenty-four hours if it’s not fertilised. You may release more than one egg over a twenty-four hour period, extending your fertility to a maximum of 48 hours. But that doesn’t mean that you can only get pregnant from sex on those two days though, as men’s sperm have a longer life-span than a woman’s egg, and it’s our combined fertility that’s important. In the right conditions healthy sperm can live for up to five days, so extending your fertile phase to about seven days in a month.
The best chance for fertilisation occurs when healthy sperm have had time to swim up into the fallopian tubes by the time the egg is released, so before you ovulate.
But how do I know when ovulation occurs?
We’ve all at some time been taught that women’s menstrual cycles last for 28 days and that ovulation takes place two weeks before your period begins, so about day fourteen. Many couples who know that they should try to conceive in the days leading up to ovulation assume that the women will ovulate around day fourteen, so see days 11 through to fourteen as the most fertile days: they may well be wrong for three reasons.
1. The 28-days cycle allows text books to produce nice, clear displays of what happens when in a woman’s cycle, but it’s only the average cycle length, a normal menstrual cycle could be anything from 24 to 36 days.
2. It’s usual to ovulate not exactly two weeks before your period, but between 12 and 16 days, so if you have a 25-day cycle you could be ovulating as early as day nine of your cycle.
3. Ovulation can vary from cycle to cycle. Plenty of women experience irregular cycle lengths, but even if you have the most regular of cycles ovulation can be delayed be several factors, like stress, travel, a shock or intensive exercise. You can only really be sure about when you’re ovulating after it has happened.
In order to predict ovulation you can either use charting methods: monitoring a combination of your waking temperature, cervical mucus and cervical position, or you can use ovulator prediction kits, OPKs which test urine for luteinizing hormone (LH). Bear in mind that charting your temperature and other fertility signs will give you more information about your reproductive cycle than an OPK and will tell you when ovulation has actually taken place as well as when it may be approaching, which is important as you may have more than one surge of LH before ovulation actually occurs.