How does a baby girl form
If a pregnant woman has a neat bump that sticks out in front like a netball, then it is a boy. If the weight is more spread out around her middle then it is a girl. Or so they say. As any mother will tell you, there is no shortage of family members and friends offering folk stories about how to tell the sex of your baby during pregnancy. The first is the size of the baby. It is true that on average baby boys weigh more at birth than baby girls, and so this could make the bump for a boy slightly bigger.SEE VIDEO BY TOPIC: How To Choose The Gender Of Your Baby
SEE VIDEO BY TOPIC: 10 Important Symptoms of a Baby Girl During PregnancyContent:
- How to make a girl or boy baby
- Intersex: When a baby isn’t quite boy or girl
- Baby Heart Rate and Gender: Can It Predict the Sex of Your Baby?
- Sex selection: Getting the baby you want
- Your Developing Baby, Week by Week
- Boy or Girl? Gender-Guessing Myths and Facts
- Fetal Development: Your Baby’s Sex
- Are You Having a Boy or a Girl?
How to make a girl or boy baby
A Newcastle University study involving thousands of families is helping prospective parents work out whether they are likely to have sons or daughters. 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. The research involved a study of family trees containing information on , people from North America and Europe going back to We now know that men are more likely to have sons if they have more brothers but are more likely to have daughters if they have more sisters.
Men determine the sex of a baby depending on whether their sperm is carrying an X or Y chromosome. On a larger scale, the number of men with more X sperm compared to the number of men with more Y sperm affects the sex ratio of children born each year. A gene consists of two parts, known as alleles, one inherited from each parent.
In his paper, Mr Gellatly demonstrates that it is likely men carry two different types of allele, which results in three possible combinations in a gene that controls the ratio of X and Y sperm;.
In many of the countries that fought in the World Wars, there was a sudden increase in the number of boys born afterwards. The year after World War I ended, an extra two boys were born for every girls in the UK, compared to the year before the war started. The gene, which Mr Gellatly has described in his research, could explain why this happened. As the odds were in favour of men with more sons seeing a son return from the war, those sons were more likely to father boys themselves because they inherited that tendency from their fathers.
In contrast, men with more daughters may have lost their only sons in the war and those sons would have been more likely to father girls.
This would explain why the men that survived the war were more likely to have male children, which resulted in the boy-baby boom. In most countries, for as long as records have been kept, more boys than girls have been born. In the UK and US, for example, there are currently about males born for every females.
It is well-documented that more males die in childhood and before they are old enough to have children. So in the same way that the gene may cause more boys to be born after wars, it may also cause more boys to be born each year. The trees above illustrate how the gene works.
It is a simplified example, in which men either have only sons, only daughters, or equal numbers of each, though in reality it is less clear cut. It shows that although the gene has no effect in females, they also carry the gene and pass it to their children. In the first family tree A the grandfather is mm, so all his children are male. He only passes on the m allele, so his children are more likely to have the mm combination of alleles themselves.
As a result, those sons may also have only sons as shown. The grandsons have the mf combination of alleles, because they inherited an m from their father and an f from their mother. As a result, they have an equal number of sons and daughters the great grandchildren.
In the second tree B the grandfather is ff, so all his children are female, they have the ff combination of alleles because their father and mother were both ff.
One of the female children has her own children with a male who has the mm combination of alleles. That male determines the sex of the children, so the grandchildren are all male. The grandsons have the mf combination of alleles, because they inherited an m from their father and f from their mother.
As a result, they have an equal number of sons and daughters the great-grandchildren. Materials provided by Newcastle University. Note: Content may be edited for style and length. Science News. Story Source: Materials provided by Newcastle University. Journal Reference : Gellatly et al. It's in the father's genes.
ScienceDaily, 12 December Newcastle University. Boy or girl? Retrieved May 20, from www. Mothers will choose a man who is only reasonably attractive for their daughters.
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Intersex: When a baby isn’t quite boy or girl
Being intersex is almost as common as having red hair, yet no one ever talks about it. Here's one family's story of raising an intersex child. By Raina Delisle March 28, After seven hours of labour , they were both eager to meet their baby, a daughter they had already named Rosalie—Rosie for short—after an ultrasound indicated they were having a girl.
Fertility Throughout Life by Lexi Krock Fetus Male: By the tenth week of pregnancy, a fetus's gender is evident, and by week 14 sex organs have formed. Female: At 20 weeks, a female fetus has a fully developed reproductive system, replete with six to seven million eggs. Infant Male: Boys do not produce sperm until puberty, so a male infant's reproductive system is largely unchanged between the fetal stage and infancy. Female: At birth, a girl's pair of ovaries contain up to 1,, follicles, which are hollow balls of cells, each with an immature egg or ovum in the center.
Baby Heart Rate and Gender: Can It Predict the Sex of Your Baby?
We can't offer any guarantees, but hey, there's no harm in trying! Are you desperate for a boy or a girl baby? Just remember, the information here is just a guide, a bit of fun. It is always the man who determines the sex of the baby. Some men just seem to make better quality X or Y sperm. Speak with your doctor about your own individual circumstances. Ditch the tight undies - ask your partner to buy some boxers or go shopping for him. Vaginal PH is normally acidic; this can be hostile to sperm. Consider taking Evening Primrose Oil supplements.
Sex selection: Getting the baby you want
Are you having a girl or boy? The sex reveal is probably one of the most exciting parts of your pregnancy. But is there any way to learn the answer without an ultrasound? How accurate are all of those stories about sex prediction, anyway?
What baby? This concept may be a little hard to wrap your head around, but even though you're technically in the first week of pregnancy, you're not quite expecting -- yet. Here's the deal: Because it's generally impossible to know the exact moment of conception, most healthcare providers count 40 weeks from the first day of your last menstrual period LMP to calculate your due date. According to this method, they date the beginning of "pregnancy" from about two weeks before the sperm penetrates the egg -- which is where you are right now.
Your Developing Baby, Week by Week
One of the most exciting things about having a child is learning the gender of the baby. Many people choose to find out as soon as possible, while others decide to keep it a surprise. Although you may not see sex organs on a sonogram for weeks, a baby's sex is determined long before it arrives in the world.
We sit around a glass coffee table. The room is clean and modern, the furnishings are that chicken soup colour favoured by architects — and expensive private clinics. Which is just where they are heading. The Gunns want a baby girl. The couple seem slightly bemused.
Boy or Girl? Gender-Guessing Myths and Facts
A Newcastle University study involving thousands of families is helping prospective parents work out whether they are likely to have sons or daughters. 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. The research involved a study of family trees containing information on , people from North America and Europe going back to We now know that men are more likely to have sons if they have more brothers but are more likely to have daughters if they have more sisters. Men determine the sex of a baby depending on whether their sperm is carrying an X or Y chromosome.
Although the evidence is not yet extensive enough to be conclusive, analysis of genetic mechanisms seems to suggest that whether a certain couple will give birth to a boy versus a girl may not be completely random i. Certain instances of conception and child-bearing may be slightly more likely to lead to the birth of a particular sex. There are several possible mechanisms that could cause this to happen.
Fetal Development: Your Baby’s Sex
The birth of Rekha's second daughter should have been one of the happiest days of her life. Instead, she lay on the bed of her home on the outskirts of Delhi, the newborn child on the floor, screaming in terror as her mother-in-law poured paraffin over her. This was her punishment, the older woman said, preparing to strike a match: Rekha had failed again to deliver a son and it would be better for everyone if she were dead.
Are You Having a Boy or a Girl?
No, the heart rate cannot predict the sex of your baby. You can even see and measure this flicker of light on an ultrasound. The beats per minute bpm start at a slow 90 to bpm and increase daily.
Beware, pregnant moms. From the moment you tell your friends or begin showing signs of a wee baby bump, the congratulations you receive will be uttered in the same sentence as, "Are you having a boy or girl? Perhaps this is our desire to envision a complete little person before the birth, a need to begin attributing characteristics, consider names, and find the perfect blue booties or pink layette. Sometimes curiosity about a baby's gender leads to some gender-guessing games that may have moms-to-be wondering: Is there any truth to those old wives' tales?