Having sex during your most fertile period is crucial but can the timing also determine if the sperm contains the X or Y chromosome?
There is no proven, hard and fast scientific evidence than anything will ensure you have a boy or a girl and often women can only take comfort in old wives’ tales as they dream of pretty pink dresses or budding little football stars!
However, the sperm containing the key chromosome X or Y have very different properties, so is it possible to give nature a nudge in one direction or the other?
The sex of your baby is determined by the chromosome present in the sperm which fertilses the egg. If the sperm contains a Y chromosome the baby will be a boy, if it contains an X chromosome, the baby will be a girl.
During each ejaculation the male releases sperm containing some X and some Y chromosomes, so it's understandable why being absolutely scientific about this race to the egg is pretty tough!
An egg will only live for 24 hours after it has been released during your cycle, unless it is fertilised, so although regular sex is recommended throughout the month when you are trying to conceive, sex around the two days before ovulation and within a few hours of ovulation is important.
Sperm containing the Y chromosome swim faster than the X ones, but they do not live as long. Also, frequent sex does tend to reduce the number of Y chromosome sperm present during each ejaculation.
Although it's not scientifically proven, some people believe that by being a little more selective about when you have sex, and having sex closer to the point of ovulation might be a good idea if you want to try for a boy, because they won't survive as long as the female sperm, but they might get to the egg first.
Sperm containing the X chromosome are larger and survive for longer after ejaculation, so they will remain active for around two days (or even three). This can make it easier to hit the right moment as ovulation is not always easy to strictly predict. However, as they are not so fast as the Y chromosome sperm, they might not win the race, if you have sex closer to ovulation.
As frequent sex can reduce the number of Y sperm present at each ejaculation, some women believe that more regular sex will help them get pregnant with a girl.
When I discovered I was pregnant, my husband was keen to find out the sex, as he’s a planner and wanted to have everything ready. I prefer surprises and persuaded him that not knowing would add to the excitement. I’d be equally happy with a boy or a girl, so there seems little to gain in finding out early.
Zara, 35, 25 weeks pregnant
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