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Recent use of the injectable contraceptive Depo-Provera for at least a year was associated with a doubling of young women’s breast cancer risk, a new study has found.

However, users’ breast cancer risk dropped to that of non-users within several months of stopping Depo-Provera injections, researchers report in the journal Cancer Research.

Depo-Provera, injected every three months, was approved as a contraceptive in the United States 20 years ago. Convenient, highly effective and relatively inexpensive, Depo-Provera is used by about 1.2 million U.S. women, or 3.2 percent of those who practice contraception, according to the latest data from the Guttmacher Institute, a research and education organization that focuses on reproductive health. 

The injectable birth control method is the only contraceptive in the United States that contains the same progestin, or synthetic hormone, as Prempro, the postmenopausal hormone therapy pill. A landmark government study called the Women’s Health Initiative found that Prempro, a combination of estrogen and progestin, increased women’s breast cancer risk by 24 percent, while Premarin, which contains only estrogen, did not increase risk.  

‘’Our hypothesis going into this study was that we did expect to see an increased risk of breast cancer associated with Depo-Provera,” says Dr. Christopher Li, a breast cancer epidemiologist at the Fred Hutchinson Cancer Research Center and lead author of the new study.

Data on the relationship between Depo-Provera and breast cancer risk are limited, the researchers write. Li and his coauthors say theirs is the first large-scale U.S. study specifically designed to evaluate the relationship. Results from similar studies conducted in other countries have been mixed, they write.

Li’s team recruited 1,028 women who’d been diagnosed with breast cancer and 919 women who had not. All the women were 20 to 44 years of age and lived in the Seattle area. About 3 percent had used Depo-Provera within the last five years.

Compared to women who had never used Depo-Provera, those who had received injections within the previous five years were 2.2 times more likely to have been diagnosed with breast cancer, the scientists found. Family history, obesity, age and pregnancy history didn’t seem to make a difference.

Age is the main risk factor for breast cancer, so while a doubling of risk might sound alarming, Li emphasizes that the actual number of breast cancer cases in women in their 20s and 30s is very low.

“Breast cancer among young women is still a rare disease,” he says. According to the National Cancer Institute, women in their 30s have a 1 in 233 chance of being diagnosed with the disease. By comparison, the odds of being diagnosed with breast cancer for women in their 60s is 1 in 29.

“However,” Li and his coauthors write, “there are numerous contraceptive options, and so further clarifying the benefits and risks associated with each option is important as women consider what choices might be best for them.”

Joan Campion, spokewoman of Pfizer, the maker of Depo-Provera, said, "As part of the Depo-Provera label, physicians are already advised on benefits and risks of Depo-Provera, including the risk of breast cancer. Pfizer currently believes that changes to benefits and risk profile are not warranted as a result of this observational study."

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Women have more sexual fantasies during fertile periods of the month, a new study finds.

The research is one of many studies finding differences in women's sexual interest across the menstrual cycle. For example, a 2007 study in the journal Hormones and Behavior found that around ovulation, when pregnancy is possible, women say they prefer macho, masculine guys. An April 2011 study even suggested that women who are in the more fertile phase of the month are more likely to see Georgia O'Keeffe's suggestive paintings as erotic.

The new study finds that sexual fantasies increase, and lead to more arousal in women, during fertile periods. Women also reported a higher proportion of men in their fantasies during fertile times of the month.

"When it mattered most, women were fantasizing more about men," said study author Samantha Dawson, a graduate researcher at the University of Lethbridge in Alberta, Canada.

Dawson and her colleagues focused on fantasies because such sexual daydreams aren't dependent on the availability of sex partners or other outside forces. That means fantasies may be more representative of sexual interest than how much real-life sex a woman has, Dawson told LiveScience. [ How to Spot a Fertile Woman ]

The researchers paid 27 single heterosexual women, mostly college students, to keep a daily online diary of their sexual fantasies for one month. None of the women were on hormonal birth control. By counting back from the last menstrual period, the researchers targeted a 10-day window in which each woman would likely ovulate.

During those 10 days, each woman took a do-it-yourself urine test to detect ovulation, much like the fertility tests available at drug stores. The tests were in neutral packaging, and women weren't told that they being tested for ovulation.

The women in the study reported, on average, 0.77 sexual fantasies a day — much higher than earlier work, which had suggested that men fantasize about once per day and women only once a week. Those earlier studies, however, asked participants to look back over time and recall their fantasies. A day-by-day approach is likely more accurate, because it does not rely so much on memory, the researchers reported online March 10 in the journal Archives of Sexual Behavior.

In the three days surrounding ovulation, fantasies became more frequent, reaching an average of about 1.3 per day. Women's reports also indicated these fantasies were more arousing than fantasies during nonfertile periods. [ Sex Quiz: Myths, Taboos & Bizarre Facts ]

The researchers expected to see fertile women become more "malelike" in their fantasies during fertile periods, given this increased interest in sex. Men generally report that their fantasies are more visual and explicit than female fantasies, which tend to contain more focus on emotion. But in fact, women actually became more femalelike in their fertile fantasies.

"They're still focusing on the emotions and the feelings that they have toward this partner in the fantasies as opposed to what the partner looks like, how masculine they are and what sexual acts they're actually engaging in," Dawson said.

The researchers did find, however, that women's interest in men peaked during fertile periods. Women are generally more fluid in their fantasies than men, Dawson said. One 2006 study presented at the International Academy of Sex Research in the Netherlands found that 25 percent of heterosexual women reported that their fantasies included other women, while only 10 percent of heterosexual men included other men in their sexual fantasies.

In the current study, 52 percent of participants reported fantasies that included women. Still, fantasies were primarily populated by men, with about 95 percent male characters across the menstrual cycle. During ovulation, however, the proportion of men went up by a percentage point or so, suggesting that fertility hormones do influence straight women's sexual interests.

"You're going to want to have sex with someone who can actually pass genes on to you, so a man versus a woman," Dawson said.

The researchers also had the women look at images of masculine and feminine men and women at three points across the menstrual cycle, but they did not find more interest in masculine men, or men in general, during fertile periods. The lack of a finding probably has more to do with the fact that the same photographs were repeated at each session than anything hormonal, Dawson said.

The message of the research is that psychologists need to be careful when studying female sexual desire, Dawson said.

"It's really important that we are conscious in these changes of female sexuality when we are researching components of women's sexual interest," Dawson said, adding that little things could make a big difference, "even the timing of when they're answering the questionnaire or when we're assessing sexual arousal."

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By MyHealthNewsDaily staff

Drinking alcohol moderately may lower women's risk of stroke, according to a new 26-year study of 84,000 women.

Women who drank low amounts of alcohol — about half of a glass of wine per day, on average — were 17 percent less likely to have a stroke compared with women who drank no alcohol. Women who drank about a glass a day were 21 percent less likely to have a stroke than abstainers.  

Those who drank more alcohol showed no reduction in stroke risk, according to the study.

The data are consistent with current guidelines for women about drinking alcohol, which suggest there is a modest reduction in stroke risk for women who drink less than one drink per day, the researchers concluded.

The study showed an association, not a cause-and-effect link, and was limited in that it relied on the participants to report their own alcohol consumption.

The study was published on yesterday (March 8) in the journal Stroke.

Alcohol and stroke risk
In the study, researchers at Brigham and Women's Hospital in Boston looked at 84,000 women who, at the study's start, had no evidence of cardiovascular disease and were between 30 and 55 years old. The researchers used data collected as part of the Nurses' Health Study, a large study of women's health that began in 1976.

Over the study, there were 2,171 strokes. Most were ischemic strokes, which occur when blood flow to the brain is blocked, depriving the brain of oxygen.

Of the 25,000 women who drank no alcohol, 1,045 suffered a stroke. Among the 29,000 women who drank lightly, 552 had a stroke, and 341 of the 20,000 who drank moderately had a stroke, according to the study.

About 30 percent of women in the study reported that they never drank alcohol, and 35 percent reported drinking very little, for example, less than half of a glass of wine per day, on average. Thirty-seven percent drank moderately — about one glass of wine or beer, or a mixed drink daily.

Only 11 percent of women reported drinking more than the equivalent of one mixed drink per day on average, and the researchers noted the small number of heavy drinkers in the study prevented them from drawing definitive conclusions about stroke risk in this group.

In general, increasing alcohol consumption was linked with being more likely to smoke and have high blood pressure, but also with doing more physical activity and having a lower body mass index, according to the study.

How it works
There are several ways the link between drinking and stroke risk could be explained, the researchers said. Alcohol may have compounds that increase "good" cholesterol and prevent blood clots. Higher levels of alcohol intake may increase the risk of high blood pressure and atrial fibrillation, which are risk factors for stroke.

The results are inline with a previous study, which found a 20 to 30 percent lower risk of stroke among men and women who drank low amounts of alcohol, compared with people who didn't drink alcohol.

The researchers noted that people who abstain from alcohol should not start drinking, due to the dangers associated with it.

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Nicotine patches do not help pregnant women quit smoking, a new study says.

Pregnant women in the study who used nicotine patches were just as likely to continue smoking until their delivery date as women who used a placebo, the researchers said.

"Clearly, standard dose nicotine patches do not work in pregnancy as well as they do in the general smoking population," study researcher Tim Coleman, of the University of Nottingham in the United Kingdom, said in a statement.The new study is the largest of its kind to address this question.

The findings support the current guidelines from the Centers for Disease Control and Prevention that advise pregnant women against using nicotine patches because they have not been shown to help with quitting, said Dan Jacobsen, a nurse-practitioner at the Center for Tobacco Control, part of the North Shore-Long Island Jewish Health System in Great Neck, N.Y.

Instead, pregnant women who smoke should use other strategies to quit smoking, Jacobsen said, including stress management. Jacobsen's center has incorporated social media into smoking cessation therapies, using text messages to encourage and support pregnant women as they try to quit.

Smoking during pregnancy can lead to a number of health complications for the baby, including miscarriage, premature birth, low birth weight and sudden infant death syndrome (SIDS).

 The study involved 1,050 women who were 12 to 24 weeks pregnant and smoked five or more cigarettes per day. Half of the women were randomly assigned to receive a nicotine patch for eight weeks, and half received a placebo patch.

After one month, the patch seemed somewhat effective: 21.3 percent of women in the nicotine patch group had refrained from smoking, compared with 11.7 percent of placebo group.

But this effect did not last. By delivery, 9.4 percent of women in the nicotine group had quit smoking, compared with 7.6 percent of the placebo group, a difference small enough that it could have been due to chance.

Very few participants actually kept up with their treatment. Just 7.2 percent of women in the nicotine group and 2.8 percent of women in the placebo group continued wearing their patchesfor more than one month.

The number of stillbirths, miscarriages and babies of low birth weight were similar in both groups, the researchers said.

Some women metabolize nicotine 60 to 120 times faster during pregnancy, which may reduce nicotine levels in their bodies and increase withdrawal symptoms. A higher nicotine dose may be needed for the drug to be effective in pregnant women, the researchers said.

Women included in the study had characteristics of people who are highly addicted to cigarettes, Jacobsen said. For instance, the majority smoked their first cigarettes within 15 minutes of waking. (The shorter the time between waking and the first cigarette, the more addicted the person is, Jacobsen said.) It's not clear whether less addicted individuals would respond better to the therapy, Jacobsen said.

Because so few women in the study adhered to the nicotine patch therapy, more research is needed to confirm it does not cause health problems in infants, the researchers said.

The study is published in the March 1 issue of the New England Journal of Medicine.

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With these twins, fame comes in a double helping.

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The number of twins born to American women has risen dramatically over the past three decades, a new government study shows.

The twin birth rate rose 76 percent from 1980 through 2009, according to report from the Centers of Disease Control and Prevention that was released Wednesday. While 189 out of every 10,000 births was a twin delivery in 1980, in 2009, 333 out of 10,000 births involved twins.

Put another way, in 2009 one in every 30 babies born in the United States was a twin, as compared to one in every 53 babies born in 1980.

Researchers  say that the uptick in twin births is due to both the increased use of infertility treatments and the tendency for women to delay child-birth till they are older.

The increase in twin births is concerning, said the study’s lead author Joyce A. Martin, an epidemiologist at the CDC’s National Center for Health Statistics.

“It’s really important to note that outcome for twins is much less positive than for singleton pregnancies,” Martin said. “Twins tend to be born earlier and smaller.. Their mothers are more likely to require hospitalization. And the twins themselves are more likely than singletons to require hospitalization."

But, Martin added, “although they are at greater risk overall, most twin births do very well.”

The rate of twinning isn’t the same all over the country. In New Mexico, for example, 223 out of 10,000 births were twin deliveries. But in Connecticut the number was far higher: 459 out of 10,000 births.  

The increases seen by Martin and her colleagues also varied by race and ethnic group. The biggest increase in twins was among white non-Hispanic mothers. For them, the rate of twins doubled over the past three decades.

Interestingly, black women have had a higher rate of twinning all along. Nobody knows why this is, but experts assume it’s mostly explained by genes, just as the tendency to twin seems to run in certain families, said Dr. Joseph Sanfilippo, a professor of obstetrics, gynecology and reproductive sciences and director of reproductive endocrinology and infertility at the University of Pittsburgh Medical Center.

It’s clear that there are big variations in women’s tendency to have twins, Sanfilippo said. That can be due to genetics and environment. Rates vary widely from country to country, Sanfilippo said. Yoruba has the highest rate with 450 to 500 sets of twins per 10,000, he added.  

The big increases Martin and her colleagues have seen in the U.S. in white non-Hispanic women have almost caught them up with black women.

While the rise in the rate of twins occurred in every age group, the biggest surges were in women 30 and older. From 1980 to 2009, the rate of twins increased 76 percent among women aged 30 to 34 and nearly 100 percent for women aged 35 to 39. Among women aged 40 and older the rate surged more than 200 percent, the Martin and her colleagues reported. 

Nobody knows exactly why older women are more prone to twinning, Sanfilippo said. But the most likely explanation is that older women have older eggs.

While these older eggs still have DNA that is intact enough to produce a healthy baby, the mechanisms that allow the fertilized egg to grow and divide may be somewhat compromised and this is what may lead to more twinning.

“The egg is the orchestra leader,” Sanfilippo explained. “If it’s been sitting around in the ovaries for 35 to 40 years it doesn’t work as well. Certainly not as well as one that is just 25 years old.”

Ultimately older moms are only responsible for one third of the increase in twins, Martin said. The rest of the surge is due to increasing use of infertility therapies like in vitro fertilization.

And that’s something that doctors and patients can control. These days more and more infertility centers are choosing to put only one embryo back into a woman’s uterus during IVF, hoping to stem the surge in multiple births.

The hope, Sanfilippo said, is that this will lead to healthier moms and babies.

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If you're the dance floor of a crowded bar - watch out for fisticuffs, says a new study.

By Cari Nierenberg

If you shake your booty on the dance floor of a crowded bar, you could be in for a world of hurt. And your lousy dance moves are not to blame. 

A recent study shows that the dance floor is the most likely place for fights to break out inside a large drinking establishment. The findings suggest that roughly 20 percent of the most harmful incidents took place on the floor itself; another 13 percent of them occurred near it.

The research, published in the journal Drug and Alcohol Review, looked at "hotspots" for aggression in bars and clubs.

In the study, researchers made more than 1,300 visits to 118 bars and clubs in Toronto over a two-year period. They went to bars that could hold more than 300 people, and they went on Fridays and Saturdays between midnight and 3 a.m.

Researchers observed the customers for aggressive behaviors, and they rated them on a scale of 1 (minor non-physical harm) to 5 (actions causing pain, including punching and kicking). They even gauged how intoxicated the customers seemed that night.

They found that the dance floor was the top spot for aggressive behavior. "There's a lot of sexual aggression and aggressive horseplay on the dance floor in late night, large-capacity bars and night clubs," says study author Kathryn Graham, a senior scientist at the Centre for Addiction and Mental Health in Toronto.

Sometimes it was just sheer numbers -- the dance floor was the most crowded place on the premises and this sparked more incidents. And partly it was because that's where the most rowdiness between dancers and even bystanders took place.

But Graham was a little surprised that the area at or near the serving bar was the second most common location for bad behavior. She figures this was mainly a traffic and congestion issue.

Tempers there could also flare between patrons and staff over drink service. And when hot heads get hammered, it can get ugly.

"I suspect that a lot of the aggression near the serving bar was in the form of male-to-male violence where egos are on the line when people get bumped," says Graham.

Then again, "It may also be that this is a good place to hang around if you're looking for trouble," she adds.

While the dance floor was the #1 hotspot for aggressive behavior and the space near the serving bar was second, the tables came in third. This was followed by the hallways, aisles, and stairs in fourth, the entrance was fifth, and the pool tables were sixth.

Although only 4 percent of incidents took place at pool tables, the area had a high rate of barroom brawls likely brought on by people's competitive juices mixing with alcohol.

So, when you head out for a night on the town, now you'll know the high-risk locations at your favorite watering hole. And feel free to pass along this research to the bar staff so they'll keep things from getting out of hand in these potential trouble spots.

The worst fights? They took place outside the bar, of course.

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By MyHealthNewsDaily

Mothers who have jobs are healthier than those who are not employed, at least when their children are very young, a new study finds.

Working mothers in the study were less depressed and reported better overall health than moms who stayed at home with their young children, though this benefit of working did not extend into children's school years.

There was no difference between the health of mothers who worked part time and those who worked full time, the researchers said.
Stay-at-home moms may be more socially isolated than working moms, which might increase their chances of being depressed, the researchers said. Stay-at-home moms might also be under more stress as a result of being at home with their children all day. This stress may be relieved somewhat when their children start school, which may explain why the link disappeared when children entered preschool.

The study is published in the December issue of the Journal of Family Psychology

The results are based on interviews, starting in 1991, with 1,364 mothers from Arkansas, California, Kansas, Massachusetts, North Carolina, Pennsylvania, Virginia, Washington and Wisconsin. Researchers interviewed women throughout their children's infancy, preschool years and into elementary school.

The researchers defined working part time as working one-to-32 hours per week. About 25 percent of mothers were employed part time during the study period, although mothers moved in and out of part-time work. Mothers reported whether they experienced symptoms of depression and rated their overall health as "poor," "fair," "good" or "excellent."

The mothers also answered questions about conflicts between their work and family lives, and how involved they were in their child's schooling.

Working moms reported fewer symptoms of depression and were more likely to rate their health "excellent," compared with nonemployed mothers, according to the study.

Mothers working part time tended to report less conflict between work and family than those working full time, the researchers said.

Mothers employed part time reported being just as involved in their child's schooling as stay-at-home moms, and more involved than moms who worked full time. In addition, mothers working part time provided more learning opportunities for their toddlers than stay-at-home moms and moms working full time, the researchers said.

Couples' emotional intimacy did not appear to be affected by the mothers' employment status: the level of emotional understanding between partners was similar for working moms and stay-at-home moms.

The findings in the study held even after the researchers took into account factors that could have influenced the results, including the mother's education and certain personality traits.

The researchers noted they examined the mother's well-being in relation to one child only, and additional siblings should be considered in future studies. 
 

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