HOUSTON, March 8 (UPI) -- An unpublished NASA report on using space missions to study women's health explicitly rejects the need for a space flight with a crew composed solely of women.

The report, obtained by UPI, was written by 12 space medicine experts assigned by NASA's National Space Biomedical Research Institute to study the value of space research focusing specifically on women's health issues.

The team made a number of recommendations but explicitly rejected the need for a flight with only women on board. "None of these recommendations require that all-female crews be flown," the report says. Critics have said NASA has delayed publishing the report -- dated Sept. 30 -- because it does not provide the hoped-for scientific justification for a project NASA proposed last year: an all-woman space shuttle mission.

Last year, NASA Administrator Dan Goldin said NASA was seriously considering flying a space shuttle with a crew of only female astronauts. The idea reportedly originated with Dr. Arnauld Nicogossian, NASA's associate administrator for life sciences. "The reason why you would fly an all-female payload crew is because the place where you can take the most data is a dedicated mission," Dr. Nicogossian told reporters in August. "We have a lot of data on white males," he said. "Now people are starting to be very sensitive to the needs of other groups."

Outside space experts were more cynical about the idea. "For NASA to assemble an all-women crew is a publicity stunt," said Dr. Patricia Santy, an aerospace medicine consultant and former specialist at NASA. "It's just to prove they're into women's issues, when in fact they haven't done anything of significance along those lines thus far." Santy is the author of "Choosing the Right Stuff," a highly respected account of screening and choosing astronauts.

NASA's Goldin said there is other value in such a mission. "The fact that young girls will see an all-women crew, I think could [be] a huge inspiration and impact on the future of education," Goldin told reporters last year. "But first we establish the science, then we establish inspiration," he added.

Since last year's initial discussions, NASA has made no further comments on an all-women shuttle mission. One original proposal had been for the STS-107 mission to carry six or seven women astronauts into orbit in November 2000.

The proximity of that flight to the 2000 presidential elections -- along with past White House enthusiasm for shuttle missions carrying John Glenn and Eileen Collins -- led some observers to suspect that political and not scientific aims were behind such activities. The Glenn mission occurred during the 1998 elections. Collins was the first woman to command a shuttle mission.

Keith Cowing, a biologist who served on NASA biomedical research review boards and who now edits the private "NASA WATCH" web site, contends that Goldin's scientific reasons for the mission are suspect. "NASA's interest in gender-based research has been minimal if not non-existent," he told UPI, "except in the public affairs office."

NASA's Dr. Nicogossian's office told UPI he had no comment on the panel's work or on any plans for official release of the report. Similar inquiries to Dr. David Williams, head of life sciences at the Johnson Space Center in Houston, went unanswered. NASA spokesman John Petty told UPI only that the study was not yet completed and he could not provide an estimate of when to expect its completion.

Women have, of course, already participated in the space program. About three dozen American women have taken part in every aspect of space shuttle missions, from space walks to actually commanding the mission. The U.S. record for the longest space flight is held by Dr. Shannon Lucid, a woman who spent six months aboard Russia's Mir space station in 1996. Of the 60 shuttle missions in the past 10 years, fully 75 percent included at least one woman in the crew. There have been two missions with six- or seven-member crews containing three women.

Yet with all this flying, NASA has avoided specific female medical research. "The issue is not that there have been no ideas about gender-related research," Santy told UPI. "The issue is that NASA has consistently rejected research in that area."

"Women wanted to be treated as 'just one of the guys,'" noted Santy. "They felt that any gender differences might be used against them," turning them into "second-class astronauts," she said.

The NASA report, which arose out of an August 1999 workshop on gender-related issues in space flight research and crew health care, echoes that sentiment and makes recommendations for gender-specific research. NASA had hoped its workshop would identify how best to accelerate research -- both on the ground and in space -- to ensure the health of diverse space crews.

Although more than thirty women have flown into space since 1983, the workshop found that NASA had paid practically no attention to female-specific medical issues. "No space-flight data exists," the report says, for topics including muscle strength and endurance, iron intake requirements or bone loss. "Several areas of concern for female astronaut health care were identified," the report says. It identifies issues associated with pregnancies scheduled between space missions so as not to interfere with training or to adversely affect the availability of women for future missions.

"The prevention of pregnancy deserves special consideration," the report says. It says there is "unknown risk" to a mother and her fetus if conception occurs just prior to a space flight. The effectiveness of birth control pills on space flights needs further study, it adds, not merely for their contraceptive applications but also because they can be prescribed for bone density maintenance. On Earth, such medication also lowers the risk of ovarian cysts, ovarian cancer, anemia and benign breast disease, as well as for controlling the timing of menstruation.

At least one of those recommendations has already raised eyebrows. Studying the effects of contraceptive drugs in space "is putting the cart before the horse," said Dr. Patricia Santy, an aerospace medicine consultant and former specialist at NASA. "They haven't even looked at the basic effects of space flight on the normal human reproductive system," she said.