January 2015 Moms
texasmama786
member
Interesting Gender Stats
texasmama786
member
The 51/49 Boy/Girl RatioThe ratio of 51% boys to 49% girls seen here is representative of overall US birth rates. There are many hypotheses about why there are slightly more boys born each year than girls, but no one knows for sure why this is so. Here are a couple of the theories:
Are Boys or Girls Preferred?The Chance study describes "stopping behavior" -- the tendency of parents to stop having children after having the desired gender or genders. Parents in the US may have a "balance preference", a desire to have one of each gender. Here's what the data shows:Did the first child's gender influence whether to have a second child?
Did previous children's gender influence whether to have a third child?
What about the fourth child?
Odds of Having a Boy or a GirlOkay, finally! Let's look at the odds of having a boy or a girl, given that previous children are all of the opposite gender.
Odds of Having a GirlThe odds of having a girl seem decrease after having each boy, but only very slightly. Even after 3 boys, you are only 6.4% more likely to have a 4th boy than a girl.
Odds of Having a BoyThe odds of having a boy seem to increase after having girls, except after 2 girls, when a 3rd girl is more likely.
Gender and Birth OrderGiven the charts above, it looks like you are slightly more likely to have a boy, regardless of previous children. This is probably due to the overall 51/49 boy/girl birth ratio. This ratio, interestingly, varies slightly with birth order; it isn't consistent among first-borns, second-borns, etc.
Odds of Having an All Same-Gender FamilyIf there are roughly even odds of having a boy or a girl with each baby, given the laws of chance we should still expect to see some all same-gender families, even in large families. Here is the number of all same-gender families we would expect to see, purely by chance:
ConclusionAlthough we often hear the "statistic" that you are 30% or even 70% more likely to keep having the same gender, this is just an old wives tale. It is NOT a fact. The truth is, your odds stay pretty close to 50% for each child and only vary slightly. If you have had 2 or 3 boys, you are only about 2% to 6% more likely to have another boy. If you have had girls, you are slightly more likely to have a boy next. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
49% Girls
25.0% Predicted
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Re: Interesting Gender Stats
Someone has already asked me if we'll have a 3rd baby to "try for a girl" if this next one is another boy, but the thought of 3 boys is scary to me.
I couldn't imagine 12 kids. Let alone all boys!
Eta: I think she team green too.
interesting fact about my family: my mother is the second of four girls (no boys) and my bio dad is the middle of five boys (no girls).
BFP#1 EDD 04.20.2010, SUNSHINE baby boy born 03.31.2010
BFP#2 EDD 12.07.2014, natural mc 04.09.2014 at 5w3d
BFP#3 EDD 01.14.15, RAINBOW baby girl born 01.16.2015
jan'15 january siggy challenge: baby fails
Interesting to see the stats laid out like this.
I remember reading somewhere a piece about increasing the odds of having a boy. They said that female sperm is hardier, copes better with alkaline environments and so can outwait male sperm for the egg to drop. So the longer sperm is waiting for ovulation, the higher the concentration of female sperm. But if ovulation has just occurred and there is no waiting, the slightly faster male sperm has the advantage. Using this logic, they suggest bd-ing/insem'ing the day of ovulation to increase the chances of a boy.
This is particularly interesting to us, since we worked out that the month we were successful, we had insem'd the day after ovulation. We've found all the old wives tales of gender prediction fascinating and have included some of them with our guess-the-gender game that went out in the family newsletter.