In the womb boys grow faster than girls and are therefore at greater risk of becoming undernourished. Fetal undernutrition leads to small size at birth and cardiovascular disorders, including hypertension, in later life.
On average, baby girls are a month ahead of boys in the number of words they understand . This may be because newborn girls are more developed on the side of the brain that's responsible for speech and language . However, the way we learn to talk is complex, and all babies will develop at different speeds.
Sex differences in the brain are reflected in the somewhat different developmental timetables of girls and boys. By most measures of sensory and cognitive development, girls are slightly more advanced: vision, hearing, memory, smell, and touch are all more acute in female than male infants.
There is a common myth among parents that boys tend to develop slower than girls. But is it true? Generally speaking, the answer is no. While girls and boys might develop certain skills on different timelines, the differences likely are not because of gender alone.
Boys mature slower physically, socially, and linguistically. Stress-regulating brain circuitries mature more slowly in boys prenatally, perinatally, and postnatally. Boys are affected more negatively by early environmental stress, inside and outside the womb, than are girls.
WASHINGTON -- Boys are slightly more likely to be born premature than girls, and they tend to fare worse, too, says a new report on the health of the world's newborns. "This is a double whammy for boys," said Dr. Joy Lawn of the London School of Hygiene & Tropical Medicine, who led the team of researchers.
They found that the most fertile months for conceiving a boy were from September to November, while the lowest fertile period was from March to May.
Moms who give birth to girls tend to have slightly longer pregnancies. Boys are more likely to be born before their due date. After the 40-week mark, however, the odds slightly favor a girl.
Scientists at Newcastle University in the U.K. have discovered that girls tend to optimize brain connections earlier than boys. The researchers conclude that this may explain why females generally mature faster in certain cognitive and emotional areas than males during childhood and adolescence.
“Male babies on average have greater difficulty self-regulating their emotional state and therefore have a greater reliance on emotional support, especially from their mother1,” he says. Research indicates that the slower development of baby boys' brains is likely due to the male hormone testosterone2.
Scientists have confirmed the fact that baby boys are harder work than baby girls. Bringing up boys takes a greater toll on mothers than girls. Boys place a greater burden on mum during pregnancy and breast-feeding, mostly because on average they are bigger than their sisters.
Some causes of early puberty in girls include thyroid disorders, abnormal brain structure, exposure to radiation therapy, or ovarian cysts. Genetic conditions may result in early puberty and can be detected with testing. In 90% of cases in girls, however, there is no known cause.
Researchers and physicians hypothesized about possible causes for the increase in early puberty, such as increasing rates of obesity; greater exposure to endocrine-disrupting chemicals found in food, plastics, and personal-care products; and stressful or abusive home environments.
Maturity is often described as a comparison between which sex is stronger: women or men. Studies have shown that girls mature earlier than boys, the same way women do than men. It is reported that women reach proper psychological maturity much earlier than men, at the typical age of 32.
When mothers gained 20 lb, roughly 49% of babies born were boys. But when mothers gained 40 lb, the likelihood of having a boy increased, with about 52.5% of babies born being males. And at 60 lb gained, about 54% of babies were boys.
First babies are less likely to be “on time” at 39 weeks, and more likely to be a little late, between 41 and 43 weeks. Among full-term pregnancies, first babies are born about 1.3 days later on average.
The least common birthday is leap day, or February 29. But because the day only occurs once every four years, it's obvious it would yield the least amount of birthdays. The rarest birthday of the 365 annual calendar days is Christmas day, Dec. 25.
A new study has revealed that people born in April are the sexiest - and having a birthday in April myself, I'm obviously completely sold on the theory…
A study done in the U.K. showed that May is the luckiest month to be born, and October is the unluckiest. It could have something to do with that optimism, since positive attitudes have been associated with greater resilience.
At birth, boys tend to be longer than girls at any placental weight. Boy's placentas may therefore be more efficient than girls, but may have less reserve capacity. In the womb boys grow faster than girls and are therefore at greater risk of becoming undernourished.
Biological sex in healthy humans is determined by the presence of the sex chromosomes in the genetic code: two X chromosomes (XX) makes a girl, whereas an X and a Y chromosome (XY) makes a boy. In this way, it is the presence or absence of the Y chromosome in a healthy human that differentiates boy from girl.
Generally speaking, the answer is no — although that doesn't mean there aren't differences between the two genders. “On average, achievement of developmental milestones in the five developmental domains — cognitive, gross motor, fine motor, communication, social-emotional — is the same in boys and girls,” Dr.
The average age for girls to start puberty is 11, while for boys the average age is 12. But it's perfectly normal for puberty to begin at any point between the ages of 8 and 13 in girls and 9 and 14 in boys.
African-American and Hispanic girls tend to reach puberty earlier than their white counterparts, research shows.