Old wives’ tales about baby gender aside, there actually exists some official data regarding your chances to get pregnant with a girl baby.
And it’s nothing less authoritative than the document issued by the USA Census Bureau!
Center for Disease Control and Prevention (CDC) has been examining the ratio of boys and girls born in the USA for the last sixty years. Its findings are published in a report Trend Analysis of the Sex Ratio at Birth in the United States, bringing some surprising facts and conclusions about what may influence the gender being born.
Since 1940, there were more baby boys being born every year than baby girls, with the sex birth ratio being the highest in 1946 and the lowest in 1991 and 2001. It was already noticed that after wars there were more boys being born than in the periods of peace. In recent times, there are fewer boys than girls being born throughout the western world.
But generally talking, for every 100 baby girls, there are about 105 baby boys.
What the data about the age structure of the mothers is telling us? The older the mother is, the more likely she will give birth to a daughter. 15-19 year old mothers have the highest sex birth ratio.
What about the nationally of mothers in regards to sex ratio? The highest differences between the number of boys and girl being born were noticed in Chinese and Filipino mothers. Non-Hispanic black and American Indian mothers had the lowest sex ratios.
First time mothers and mothers with other children? The more children a woman has, the more likely she is going to give birth to an equal number of boys and girls.
We know how the gender is chosen (in 1959 the sex chromosomes are discovered) but still don’t know exactly how it is done.
P.S. I’ve found an online test that predicts your probability of getting pregnant with a boy or a girl baby in percentages. According to this test, I’ve got a 20% chance of conceiving a boy in the following months, and, consequently – a 80% chance of getting pregnant with a girl baby.
It looks like the test is based on scientific facts about female dominance as measured by testosterone levels and the resulting sex ratio. I have already posted about the scientific findings that show how low testosterone women have more girls. You’re supposed to self assess your temperament – and then, that personal characteristics somehow translate in having a low or high testosterone. A (prospective) father can complete this test, too.
If you’re intrigued, the further reading is available in a book by Valerie J. Grant: Maternal Personality, Evolution and the Sex Ratio: Do Mothers Control the Sex of the Infant?
