SYDNEY, Australia -- The world's first injectable male contraceptive is a step closer to reality, Australian scientists have said.

A five-year study, conducted by the ANZAC Research Institute in Sydney, involved 55 men using hormonal injections and implants as birth control. None of the men's partners conceived and there were no side effects compared to other trials, which have been terminated due to unforeseen problems. The contraceptive works by inhibiting sperm production through injections of progestin every three months. Since this hormone also reduces the sex drive, testosterone had to be implanted under the men's skin every four months to maintain their libido.  After a 12-month period, participants would stop the treatment to recover their fertility. It is a method that proved entirely successful for Chris Hains, a police officer from Sydney, whose wife became pregnant seven months after he stopped taking the injections, according to media reports.

"This is the first time a reversible male contraceptive that will suppress sperm production reliably and reversibly has been fully tested by couples," Professor David Handelsman, the study's director, was quoted by Reuters as saying. He added that it was up to pharmaceutical companies to follow up the research with a commercial product, but said a single injection could easily be administered by local doctors every three to four months. But Melissa Dear, a spokesperson for the Family Planning Association, told CNN that she thought it was unlikely that the final product would be marketed in the form of an injection. "It's too awkward a method," she said. "This study has brought the reality of the male contraceptive pill one step closer, but we need to look at combining both hormones in a tablet form." She added that although the Family Planning Association welcomed the news, she anticipated that it would be five to 10 years before a male contraceptive was available commercially. "You'd be bonkers if you believed a man who told you he was on the pill today," she said.

How Sleep Can Battle Cancer
A good night's sleep is right up there with chicken soup as a cure-all. But can it help someone beat cancer? A growing body of research suggests it might, according to an article in the current issue of Brain, Behavior and Immunity. Stanford University's Dr. David Spiegel and his colleagues point to studies showing that shift workers have higher rates of breast cancer than women who sleep normal hours. Two possible culprits are the hormones melatonin and cortisol. Melatonin is an antioxidant that mops up damaging free radicals, but the body produces less of it when sleep cycles are disrupted. Cortisol, which helps regulate the immune system, may also be compromised by troubled sleep. Says Spiegel: "Cancer might be something to lose sleep over, but we'd rather help people regain the sleep and lose the cancer." Cancer: In Kids And Their Moms
Could cancer in a child be somehow linked to breast cancer in the mom? That's the strong implication of a study presented last week at the European Cancer Conference in Copenhagen. Tracing the medical histories of 2,600 mothers whose children developed various cancers before age 15, researchers discovered that breast cancer was diagnosed in 95 of the women--30% more than predicted. The earlier the kids got cancer, the greater the danger. Mothers of children who got sick before age 6 had a 50% greater-than-expected risk of getting breast cancer. The risk was higher in the early years after giving birth to the child and greater in the mothers of boys. Scientists believe the link may have to do with mutations on the tumor-suppression gene p53 and with disruption of hormone levels inside the womb.

Report: U.S. kids living longer, getting fatter

(CNN) -- Children in the United States are living longer, smoking less and graduating high school at higher rates, but they also are getting fatter, according to an annual U.S. government report released Friday.

The Report on America's Children 2003, released by the National Institutes of Health and the Census Bureau, as well as other agencies, evaluated children's well-being in economic security, health, behavior, social environment and education categories. This year's report shows that overall, today's nearly 73 million children are doing better than ever before. 

"Contrary to what many people may think, the nation's children are faring better in many respects than they have in previous years," said Dr. Duane Alexander, director of the National Institute of Child Health and Human Development. Improvements were seen in the childhood death rate, which reached record lows, and the infant mortality rate, which has been steadily decreasing. The study found the rate receded from about 11 deaths per 1,000 live births in 1983 to about seven in 1,000 in 2000.

U.S. children are giving up cigarettes. The number of teenagers who smoke daily dropped to the lowest numbers since the government began surveying in 1975. Seventeen percent of students in 12th grade reported smoking, while 5 percent of eighth-graders and 10 percent of 10th graders did. The number of those finishing high school rose slightly to 87 percent in 2001, with more taking harder classes, such as honors-level English and math courses. Graduates in 2000 were also more likely than students in the past decades to have taken a foreign language class.

This is the first year the report has included the weights of U.S. kids, citing too much poundage as a serious public health concern. The number of children ages 6 to 18 who were overweight increased from 6 percent two decades ago to 15 percent in 1999-2000. "That's two-and-a-half times what it was just 20 years ago," Edward Sondik, director of the National Center for Health Statistics, told Reuters. "Even more striking than that ... if you look at the figures for black children, 22 percent of black children are overweight. ... This really is a major concern."

Among the report's other findings: • Not as many teenage girls are having babies. The report said in 2001, there were 25 births for every 1,000 girls ages 15 to 17 -- down from 27 per 1,000 for this age group in 2000. The birth rate for African-American females in this age group decreased by nearly half -- from 86 per 1,000 girls to 45 -- from 1991 to 2001. • Fewer children are living in families with married couples. The study reported that finding dropped from 72 percent in 1990 to 68 percent in 2000, with Utah having the most in both years. •  The number of children ages 3 to 5 attending preschool programs has risen. The numbers added up to 61 percent in 2000, compared with 42 percent in 1990. • The child poverty rate, which remained steady at 16 percent overall, continued to decline for black children with females as the heads of household, down two points to 47 percent in 2001. • Tenth graders aren't drinking alcohol as much as in the past. In 2001, 25 percent reported episodes of heavy drinking, while a year later, the rate was at 22 percent. Illegal drug use also dropped slightly in the same age group.