On the other hand, having sex from 2 days before ovulation, through a few days after ovulation, is better for conceiving a boy. Around the 2-day point, 48 hours before ovulation, seems to be the 50/50 mark. (2) The pH of the women's tract is also very important.
Nature is designed to favour the conception of boys from September to November and girls from March to May because of an evolutionary mechanism aimed at keeping the overall sex ratio as near to 50:50 as possible, the scientists said.
The key to conceiving a boy is to do “the deed” close to your ovulation. As Dr Shettles points out, male-producing sperm (Y-chromosome) move faster than female sperm. Male sperm also dies pretty fast, while female-producing sperm (X-chromosome) can stick it out and take their time hooking up with the egg.
Every egg has an X sex chromosome; a sperm can have either an X or a Y sex chromosome. If the sperm that fertilizes an egg has an X chromosome, the baby is female; if it has a Y chromosome, the baby will be a boy.
There are many ideas about ways to influence baby's sex and how to conceive a boy or a girl, but these are mostly myths or "old wives' tales" that aren't supported by modern science. The only reliable way to choose a baby's sex is by using IVF with genetic testing.
The ratio of male to female births, called the sex ratio, is about 105 to 100, according to the World Health Organization (WHO). This means about 51% of deliveries result in a baby boy.
The proportion of male babies was significantly higher (65.5 +/- 3.9 per cent, mean +/- S.D.) in the offspring of women who resumed intercourse two days after ovulation. This proportion tended to be lower on or near the day of ovulation than on the previous one or two days.
Almost everyone has around a 50% chance of having a boy and a 50% chance of having a girl. What we can say is that dad's sperm determines whether a baby will be born as a boy or a girl. About half of his sperm will make a boy and half a girl. The sex of the baby depends on which sperm gets to the egg first.
Men determine the sex of a baby depending on whether their sperm is carrying an X or Y chromosome. An X chromosome combines with the mother's X chromosome to make a baby girl (XX) and a Y chromosome will combine with the mother's to make a boy (XY).
Women are just XX. That's their genetic makeup; whereas men are XY. Therefore, the only genetic material a woman can contribute to her egg is an X chromosome, whereas men can make sperm that have either an X or a Y.
According to conventional wisdom, an embryo becomes a boy when a gene on the Y chromosome triggers the development of testes, which then begin to produce male sex hormones, including testosterone, at about the 8th week of gestation.
Participants, methods, and results
Among the 498 (9.4%) women with times to pregnancy longer than 12 months, the probability of male offspring was 57.6% (287), whereas the proportion of male births among the 4785 women with shorter times to pregnancy was 51.1% (2445, χ2 = 7.81, P = 0.0052).
50/50 chance of each. It depends on which sex of sperm gets to the egg at the right time, and sperm don't know you were ever pregnant with a boy or girl. It's like flipping a coin every time you get pregnant. 50/50 chance of each.
If the sperm that fertilizes a woman's egg is X, then she'll have a girl. If the fertilizing sperm contains a Y chromosome, then the baby will be a boy.
According to Shettles, timing sex as close to or even after ovulation is the key to sway for a boy. Shettles explains that couples trying for a boy should avoid sex in the time between your menstrual period and days before ovulation. Instead, you should have sex on the very day of ovulation and up to 2 to 3 days after.
If you're wondering what time of day to have sex to conceive, the morning may be your best bet. Or, specifically, after your partner gets a good night's rest, says Melissa M. Goist, M.D., Assistant Professor of Obstetrics and Gynecology at The Ohio State University Medical Center.
It takes about 24 hours for a sperm cell to fertilize an egg. When the sperm penetrates the egg, the surface of the egg changes so that no other sperm can enter. At the moment of fertilization, the baby's genetic makeup is complete, including whether it's a boy or girl.
Best positions: deep penetrative sex is preferable. This helps to deposit the semen and sperm closest to the woman's cervix so they are given the best opportunity to get to the egg in the fallopian tube. Twelve hours before ovulation is thought to maximise the chances of conceiving with a boy.
For healthy semen samples collected between 5:00am and 7:30am were found to exhibit a statistically higher sperm concentration, total sperm count and a higher percentage of normally shaped sperm, compared to samples produced later in the day.