This is BS. All around the world, the physical size, growth and development of babies from birth to 36 months is gauged using two distinct sets of charts - one for boys, the other for girls. Because from the get-go, the normal ranges of head circumference, body length, body weight, and weight gain for babies and toddlers differ depending on sex.
Anyone who's had babies, raised them or been involved in hands-on care of little ones knows that girls are at special risk of UTIs and thus require special attention when diapering, and that there are number of health conditions affecting the genitals and urinary anatomy only of male children. These include cryptorchidism, hydrocele, hypospadias, phimosis and parphimosis and testicular torsion.
Some very serious diseases that appear, and need to be treated, starting ASAP in early childhood such as hemophilia and X-linked severe combined immune deficiency (SCID-X1, aka "bubble boy disease") occur only in males.
A significant number of health conditions that can affect children of both sexes occur at different rates, manifest differently, require somewhat different diagnostic procedures, and respond to treatment differently, depending on the child's sex.
When children have severe abdominal pain, for example, their sex needs to be taken into account because the cause might be related to sex-specific internal organs such as the ovaries or uterus.
Boys are at higher risk of childhood cancers across the board, and this appears unrelated to the fact of boys' higher average birthweights and faster growth rates.
Male sex is associated with an increased risk of a number of childhood cancer types, these associations are not mediated by birthweight, and are independent of other perinatal risk factors
Suspected biological mechanisms may be rooted in differences in sex chromosome gene expression or methylation or may be due to differences in immune function between males and females during infancy and childhood. Characterization of genomic differences on the X chromosome between males and females during prenatal development and childhood will be important for discovering the underlying biologic mechanisms responsible for the observed sex differences in childhood cancer risk.
Some diseases including cancers that occur in both sexes nevertheless occur in males and females at different rates, have different trajectories, respond to treatments diferently, have different survival rates, and lead to or are associated with different risks of developing other kinds of health problems later on in life. All because of sex.
The sex differences in cancers that aren't specific to one sex or the other appear to be independent of current sex hormone levels, too:
males are more likely to develop malignant brain tumors than females at all ages, including in childhood. This suggests that the disparity cannot be explained solely by the effects of circulating sex hormones.
“The fact that we see sex differences in cancers in young children and young adults, as well as post-menopausal adults, means that circulating sex hormones are not responsible for the differences,” said Dr. Rubin.
When circulating sex hormones affect a disease, there are changes in the frequency and severity of the disease that parallel sex hormone levels, he continued. “That is not the case for sex differences in most cancers.”
“We see a big difference in the incidence of glioblastoma between men and women and between boys and girls,” said Dr. Rubin. Males are 60% more likely to develop glioblastoma overall than females.
Initial tumor growth velocities were similar for both women and men, but only women experienced a significant decline in tumor growth after treatment with the chemotherapy drug temozolomide (Temodar), which is commonly used to treat glioblastoma, the researchers found.
“The MRI studies indicated that the standard treatment for glioblastoma is more effective for females than for males,” said Konstantin Salnikow, Ph.D., of NCI’s Division of Cancer Biology (DCB), who was not involved in the study.“