A slightly greater number of males than females are born worldwide every year. In recent decades, although there are still more baby boys born than girls, there has been an apparent decline in the ratio of male to female newborns in several industrialized countries, including Canada, Denmark, England, Germany, Japan and the United States.
That has led researchers to ask: Are there any factors that can influence the probability of giving birth to a baby boy or girl? A new study from the Harvard School of Public Health (HSPH) and Karolinska Institutet in Stockholm, Sweden, found that mothers who experienced an increase in weight from the beginning of the first pregnancy to the beginning of the second pregnancy may be slightly more likely to give birth to a baby boy during their second pregnancy. The study appears online September 24, 2007 in the journal Fertility & Sterility.

"The results are provocative because few biological factors are known in humans to influence the chances of either conceiving or carrying to term a baby boy or girl. Our study suggests that maternal nutritional factors might play a role," said Eduardo Villamor, assistant professor of international nutrition at HSPH and lead author of the study.

Some prior studies had looked at what factors might influence the sex ratio, but evidence of causality has been weak. Parental smoking, for example, has been associated with both lower and higher sex ratios. Maternal nutritional status had been studied, but there was little evidence to support a causal relationship with the sex ratio. One of the hypotheses that the authors of this study wanted to test was whether the increase in maternal obesity in several industrialized countries could play a role in the declining sex ratio. Their study found the opposite--maternal weight gain seemed to favor the birth of boys.

The study population, drawn from the Swedish Birth Registry, included 220,889 women who had successive pregnancies between 1992 and 2004 (live births and stillbirths were included). The researchers analyzed the change in women's body mass index (BMI) between the first and second pregnancies. (BMI is weight in kilograms divided by the square of height in meters.) The male to female sex ratio of the second pregnancy increased linearly with the amount of weight change from the first to second pregnancy, from 1.024 in women who lost more than 1 unit BMI to 1.080 in women who gained 3 or more units (a male to female sex ratio of 1.000 would indicate an equal number of boys and girls being born). The trend was independent of obstetric complications, maternal smoking, parental age, length of the interpregnancy interval and the sex or survival status of the first-born child.

The data suggest that interpregnancy weight gain appears related to a slight increase in the probability of giving birth to a baby boy during a second pregnancy. The obesity epidemic does not appear to explain the observed decline in the sex ratio in some industrialized countries, which indicates that there are factors still unknown influencing the probability of giving birth to boys or girls.

The authors are careful to note that women should not gain weight to try to influence the sex of their baby. "Weight gain before pregnancy carries significant risks to the mother and the baby, and should not be practiced to influence the odds of having a boy," said Villamor. "Other factors of which weight gain is only an indicator could be at play here."PregnancyAndBaby.com

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Liam's mother and father, Leighton and Colleen Friesen, were definitely additionally sued for really unable to show their particular young man with "proper habits."

This unique throughout flipped initiated other remarks by Liam and his mother and father and also Southridge, against oneself.

The idea may get more technical. With regards to element, your Friesens sent in thirdparty recognize from Age in addition to the woman's momma Tracy Tichelman, proclaiming Age recognized, and also ought to have acknowledged, which the activity the woman participated in which is, piggybacking had been likely to induce injury to her own many other student.

Elizabeth's mother, that it was believed, "failed to teach the woman's daughter to prevent yourself from this kind of thinking.Inches

The youngsters claimed several years afterwards, in a three daytime long trial period in Calgary for 2011, along with The legal Terry Schultes presiding.

Schultes determined Liam in charge however , observed virtually no foundation to seek out his / her moms and dads accountable.

"Here the data was initially with suitable attempts by means of Mr. as well as Mrs. Friesen for you to practice Liam when needed to get a misbehaviour at your house,Half inch a appraise listed. "There was not a previous carry out through him fitness center institution which would possess facilitated these people to predict in addition to behave to prevent her liable pressing for Jacqueline."

Schultes also sacked Jaqueline's says versus Southridge, in addition to the vacation remarks. Your dog couldn't refer to any kind of monetary volume or honor in his factors that cause determination.

Survive May possibly, so was initially in advance of Schultes yet again. This period, any Tichelmans tried for an investment associated with exceptional rates about the Friesens, or perhaps an purchase providing impact to be able to

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The particular Friesens obtained provided to decline its state in opposition to Tracy Tichelman within May 2012 offering your lover didn't do charges from these folks however their lawyer or attorney fixed if Mr. together with Mrs. Friesen put together at fault, he reason that all of the father and mother should really be. A Tichelmans rejected testosterone

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Trainer Robert McCarthy claimed Friday he's going to follow variety through the recent years and participate in their starters only some photographs while in the preseason ending alongside Blue springs this week.

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