A couple who wanted to beat the family 'tradition' of having boys have used the decades-old 'Shettles Method' to give them the first girl in 100 years and 4 generations on the husband's side - and say part of that means having 'boring' sex.
Say WHAT?! ?
Mum Hollie, a hypnotherapist, told The Mirror:
"There were so many theories and old wives' tales but we dismissed those and thought we would go with science and use the Shettles Method.
"The theory is, if you have sex two to three days before you ovulate, the sperm which gives you a boy dies off quicker so gives you the chance to have a girl.
"As well as the time of having sex, they also say that if a woman enjoys the sex and has an orgasm it can release the egg early. So you basically have to have boring sex.
"So we had boring sex to give us the best chance."
More about the Shettles Method
If you read our science bit below you'll find our more about how the X and Y chromsomes work - and the sperm bit.
And we'd certainly heard this theory before at MFM - though the 'boring' sex bit was a new one to us.
Devised by Dr Shettles in the 1960s, the Shettles Method talks about the timing of sex affecting the baby's gender, but also touches on how having multiple orgasms, or no orgasm, can affect the baby's sex, too.
Waves of orgasm can help draw up the sperm quicker to the egg (according to Shettles), giving the male sperm more of a chance to ovulate the egg.
No orgasm means the egg is released slower which means the boy sperm may be more likely to die off before they reach it.
We have to say though - there is no proven, hard and fast scientific evidence that anything will ensure you have a boy or a girl - not to mention that you can of course have very 'unboring' sex without orgasm ?
However, the sperm containing the key chromosome X or Y do have very different properties, so is it possible to give nature a nudge in one direction or the other?
It's all in the chromosome
The sex of your baby is determined by the chromosome present in the sperm which fertilzes 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.
Go Y! - the male chromosome
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.
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Go X! - the female chromosome
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.
Tara is mum to 1 daughter, Bodhi Rae, and has worked as Content Editor and Social Media Producer at MadeForMums since 2015
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