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.
Speed: since sperm containing the Y chromosome are faster than those containing the X chromosome, if the egg is in the fallopian tube at the time of intercourse, there is a greater probability of a Y sperm reaching and fertilising it, which means there is a greater probability of the baby being a boy.
Because male sperm is the faster of the two, Shettles suggests having intercourse as close to ovulation as possible, so the male y sperm can reach the egg first. If you have sex several days before the day of ovulation, the less resilient male sperm may die off. This leaves more female sperm to fertilize the ovum (5).
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.
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.
Morning may be the best time to have sex for conception, at least as far as sperm are concerned. Some studies have suggested that sperm count and quality are slightly higher early in the morning, which may mean better odds of conception if they're deposited right after a good night's sleep.
The only way to select the sex of your baby
The only true way to select the sex of your baby is by undergoing IVF with preimplantation genetic testing (PGT). IVF is a reproductive treatment in which eggs are fertilized by sperm in a laboratory.
The work by Corry Gellatly, a research scientist at the university, has shown that men inherit a tendency to have more sons or more daughters from their parents. This means that a man with many brothers is more likely to have sons, while a man with many sisters is more likely to have daughters.
While historically, there have been about 105 boys born for every 100 girls worldwide — which creates a “sex ratio at birth” of 1.05 — the share of boy babies has increased in recent decades. 2011 data from the World Bank show the global sex ratio at birth is now 1.07, or 107 boys born for every 100 girls.
A child's biological sex (male or female) is determined by the chromosome that the male parent contributes. Males have XY sex chromosomes while females have XX sex chromosomes; the male can contribute the X or Y chromosome, while the female must contribute one of their X chromosomes.
Because, although the Shettles Method offers a 70-90% chance of conceiving a baby of the preferred gender, it does not really take into account the individual factors which so strongly influence whether a baby boy or a girl baby will be conceived. Luck is certainly a factor in the Shettles Method.
Pregnant women carrying girls have a greater chance of experiencing nausea and fatigue, according to the results of a study from the USA's Ohio State University Wexner Medical Center.
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.
Male Fertility Facts
Peak male fertility is around 25-29 years old. Sperm quality begins to decline at 30. At 45, men begin to experience a significant decrease in semen volume. Older men can also take longer to conceive a child.
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 age where a man is most fertile is between 22 and 25 years. It is suggested to have children before the age of 35. After this age, the male fertility begins to worsen. After 35, the sperm might result in pregnancies where mutations can occur.
For a boy, sperm with the Y chromosome should be deposited as close as possible to the egg because the Y chromosome has a short lifespan and it will not live longer than 24 hours, compared with the sperm with the Y chromosome which will live in a woman's body for up to 72 hours.
When sperm are inside women's body, they can live for up to 5 days. If you're a man and you have sex even a few days before your partner ovulates, there's chance they may get pregnant.
A baby conceived in the light of the Moon (from new Moon to full Moon) will be a boy; a baby conceived in the dark of the Moon (from full Moon to new Moon) will be a girl.
Fertility treatment
Some fertility drugs work by stimulating a woman's ovaries, which can sometimes cause them to release more than one egg. If sperm fertilizes both of these eggs, this can result in twins. In vitro fertilization (IVF) can also increase the chance of conceiving twins.