Wednesday, August 24, 2005

Reports Examine Stage At Which Fetuses Feel Pain

A review of medical evidence concludes that fetuses likely do not feel pain until the final months of pregnancy, challenging claims by abortion opponents who hope that discussions of fetal pain will make women think twice about ending pregnancies.

Critics disputed the findings and called the report biased.

The review by researchers at the University of California at San Francisco comes as advocates are pushing for fetal pain laws aimed at curtailing abortion. Proposed federal legislation would require doctors to provide fetal pain information to women seeking abortions when fetuses are at least 20 weeks old and to offer women fetal anesthesia at that stage of the pregnancy. A handful of states have enacted similar measures.

The report in the Journal of the American Medical Association said offering fetal pain relief during abortions in the fifth or sixth months of pregnancy is misguided and might result in unacceptable health risks to women.

The researchers reviewed dozens of studies and medical reports and said the data indicate that fetuses likely are incapable of feeling pain until around the seventh month of pregnancy, when they are about 28 weeks old.

While brain structures involved in feeling pain begin forming much earlier, research indicates they probably do not function until the pregnancy's final stages, said senior author, UCSF obstetric anesthesiologist Mark Rosen.

Kanwaljeet Anand, a fetal pain researcher at the University of Arkansas for Medical Sciences who believes fetuses as young as 20 weeks old feel pain, said the authors excluded or minimized evidence suggesting fetal pain sensation begins in the second trimester and wrongly assume that fetuses' brains sense pain in the same way as adult brains.

Study Shows Aspirin Cuts Risk Of Colon Cancer in Women

Women who took regular doses of aspirin for a decade cut their risk of colorectal cancer by as much as half, according to a study that might help settle conflicting views on how the drug affects the disease.

The study, in the Journal of the American Medical Association, showed that taking two aspirin a week for 10 years trimmed the risk by 23 percent and that taking two every day halved it.

The research tracked more than 80,000 women over 20 years.

"It was the highest doses, well beyond those examined in previous studies, that were most beneficial," said lead researcher Andrew Chan, a gastroenterologist at Massachusetts General Hospital in Boston.

The researchers tracked 82,911 women enrolled in the Nurses' Health Study who answered questionnaires on their health habits, including diet and medication use, every other year since 1980.

Chan said it is too soon to recommend general use of aspirin to ward off colon cancer because those drugs carry side effects such as ulcers and bleeding in stomach.

No Slowdown Foreseen In Rate of Arctic Ice Melting

The rate of ice melting in the Arctic is increasing, and a panel of researchers says it sees no natural process that is likely to change that trend.

Within a century, the melting could lead to summertime ice-free ocean conditions not seen in the area in a million years, the group said yesterday.

The findings of the National Science Foundation's Arctic System Science Committee were published in yesterday's issue of Eos, the weekly newspaper of the American Geophysical Union.

The report was issued following a week-long meeting of scientists that examined how the Arctic environment and climate interact, and how that system would respond as global temperatures rise.

In Small Study, Dummy Pills Help Alter Brain Chemistry

Dummy medications known as placebos trigger changes in brain chemistry, showing that the effect is more than psychological, according to a study in the Journal of Neuroscience.

Researchers gave placebos to 14 people with jaw pain and then watched for the brain's response using positron emission tomography. The imaging showed elevated levels of pain-fighting endorphins in strategic areas of the brain, said Jon-Kar Zubieta, a neuroscientist at the University of Michigan at Ann Arbor, who led the study.

Scientists have debated for years whether placebos create a psychological effect or trigger real change in the body.

-- From News Services

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