UPI NewsTrack Health and Science News

Abstinence pledge ineffective, study shows

BALTIMORE, Dec. 29 (UPI) -- Teens signing pledges to remain virgins until marriage are likely to engage in premarital sex and more likely not to use birth control, U.S. researchers report.

The analysis of federal survey data found more than half of teens became sexually active before marriage regardless of a "virginity pledge," The Washington Post reported Monday.

"Taking a pledge doesn't seem to make any difference at all in any sexual behavior," said Janet Rosenbaum of the Johns Hopkins Bloomberg School of Public Health in Baltimore. "But it does seem to make a difference in condom use and other forms of birth control that is quite striking."

Rosenbaum said she compared 289 students who were 17 years old on average in 1996, when they took a virginity pledge, with 645 who didn't take a pledge but otherwise showed similar attitudes about sex and birth control. By 2001, Rosenbaum found 82 percent of those who had broken their no-premarital-sex promise and and there was no significant difference in the proportion of students in both the pledgers and non-pledgers engaged in sexual activity.

"It seems that pledgers aren't really internalizing the pledge," Rosenbaum told the Post. "It seems like abstinence has to come from an individual conviction rather than participating in a program."

She said she found about 24 percent of those who had taken a pledge said they always used a condom, compared with about 34 percent of those who had not. The finding could be attributable to what teens learn about condoms in abstinence programs, she said.

Human hair works as nutrient, study finds

STARKSVILLE, Miss., Dec. 29 (UPI) -- Human hair, normally swept and tossed from barber and beauty shops, can be used as a nutrient source for container plants, U.S. researchers said.

A study indicates human hair cubes could, in some instances, support plant growth in horticulture crops as the plants' sole source of nutrients, the American Society for Horticultural Science said Monday in a news release.

The study by Mississippi State University researches studied productivity lettuce, wormwood, yellow poppy and feverfew. They reported finding crops receiving hair waste cubes had increased yields when compared with the control group of untreated crops, but were lower than yields receiving inorganic treatments.

Once hair waste starts to degrade, "it can provide sufficient nutrients to container-grown plants to ensure similar yields to those obtained with the commonly used fertilizers in horticulture," researcher Vlatcho Zheljazkov said. "However, it takes time for the hair to start degrading and releasing nutrients, as is reflected in lower yields in the hair treatments relative to the inorganic fertilizers for lettuce and wormwood."

Because of possible health concerns, the researchers said more study was needed to determine whether human hair waste is a viable option as fertilizer for edible crops.

Female circumcision prevalent in Kurdistan

BAGHDAD, Dec. 29 (UPI) -- Female circumcision is widespread in Iraq's Kurdistan region, despite it having what is considered a more progressive society, women's advocacy groups say.

A study this year indicates more than 60 percent of women in Kurdish areas of northern Iraq have been circumcised, and in at least one territory 95 percent of women have undergone the ritual, The Washington Post reported Monday.

The practice -- involving the removal of external female genitalia -- and the Kurdish Parliament's refusal to ban it, point up the plight of women in the region, say advocacy groups, which call it female genital mutilation.

"When the Kurdish people were fighting for our independence, women participated as full members in the underground resistance," said Pakshan Zangana, leader of the women's committee in the Kurdish Parliament. "But now that we have won our freedom, the position of women has been pushed backward and crimes against us are minimized."

Zangana has been lobbying for a law in the semi-autonomous Kurdistan that would impose jail terms on those who perform or facilitate female circumcision. But the legislation has stalled for nearly a year, in part because of what women's advocates believe is reluctance by senior Kurdish leaders to shine a spotlight on the custom.

Supporters told the Post the practice has been a ritual in their culture for generations and is based on sayings attributed to Muhammad. Supporters also said the practice controls a woman's sexual desires and it makes her spiritually clean so that others may eat meals she prepares.

Competition may have done in Neanderthals

LAWRENCE, Kan., Dec. 29 (UPI) -- Competition with Cro-Magnon populations, not climate change, led to the Neanderthal extinction, a multidisciplinary U.S. and French research team reported.

By comparing reconstructed areas for Neanderthals and the more modern humans during several climatic phases and projecting each niche onto the subsequent climatic phases, scientists from the University of Kansas and the French Center National de la Recherche Scientifique and l'Ecole Pratique d'Hautes Etudes determined Neanderthals could maintain their range across Europe during a period of less severe climatic conditions, the researchers said in a joint news release.

However, archaeological records indicate this didn't happen, researchers said. Their mathematical models predict the southern limit of the modern human territory near the Ebro River Valley in northern Spain shifted between periods.

Researchers conclude that Neanderthal populations occupying modern-day southern Spain were the last to survive because they avoided direct competition with Cro-Magnons, since the two populations settled in distinct territories during cold periods. The scientists added that any contact between Neanderthals and modern humans could have allowed cultural and genetic exchanges.