Do microwave ovens adversely affect pregnant women? Are home-canned goods safe to eat after 15 years? Is laser surgery effective in treating kidney stones? Answering these questions and thousands like them is all in a day's work for a special group of health organizations -- federally sponsored information clearinghouses.

Despite long titles and cumbersome acronyms, these operations in fact simplify the flow of information.

"The idea was to make information from the federal government accessible, as well as information that was floating around on the outside," says Joanne Angle, Director of the National Health Information Clearinghouse (NHIC).

"We are information brokers," echoes Muriel Levin of the National Digestive Diseases Education and Information Clearinghouse (DD).

Many inquiries received by NHIC are referred to one or more of the 2,000-plus organizations -- both government and private -- on the clearinghouse's data base. For example, an occupational nurse needing materials on the potential health hazards of video display terminals was referred to the National Center for Devices and Radiological Health and to 9-to-5, the National Association of Working Women.

An inquirer seeking a support group for parents of emotionally disturbed children was referred to Parents Helping Parents. Information on the dangers of mercury in amalgam fillings was obtained from the National Institute of Dental Research.

Under the umbrella of the Department of Health and Human Services, information clearinghouses are set up to meet perceived public health needs. Many had their genesis in a 1979 surgeon general's report that outlined comprehensive national health goals.

They typically support a government initiative, such as the office of Disease Prevention and Health Promotion or the Division of Maternal and Child Health, says Patricia President, associate director of NHIC. Some are operated within HHS, but many are run under contract by private enterprises.

While some clearinghouses are geared primarily to health professionals, a dozen or so are expressly or equally committed to educating consumers.

Most focus on a specific area, such as alcohol, digestive diseases, drug abuse or maternal health. In addition to developing data bases, they may also maintain libraries, carry on research or develop and distribute a wide variety of printed materials.

Best of all, the information they provide is free.

Because it is uniquely comprehensive, NHIC is primarily in the referring business, a "middle man" in information transfer, as Angle puts it. "We have tried to centralize access to information; we don't really collect it," she says.

The clearinghouse offers "one-stop shopping": staffers will initiate contact with numerous referral organizations, when necessary. According to Linda Malcolm, information services manager, the clearinghouse receives inquiries on every conceivable health topic, including major diseases, nutrition, prescription drugs and paying for health care.

But "generally, anything that appears in the news, eventually we'll get a call about," she says. Herpes, AIDS (acquired immune deficiency syndrome) and eating disorders were last year's hot topics. More recently, four physicians wishing to volunteer their skills to Ethiopia's famine relief effort turned to NHIC for advice.

When no referral organization exists on a particular health concern or when information is needed immediately, information specialists will try to find an answer using an in-house library or through further research. Rarely is the clearinghouse totally stymied.

The so-called "end-user" clearinghouses print fact sheets with basic information or with answers to common questions. For example, the National Information Center for Handicapped Children and Youth (NICHY) publishes fact sheets on spina bifida and dyslexia. DD has compiled similar information about gallbladder disease and colitis.

Maintaining information about peer support groups and local consumer resources is typically an important priority.

Clearinghouses may also publish pamphlets, abstracts of current research and periodicals. "Healthfinders," an NHIC series, features lists of resources on a variety of subjects ranging from toll-free numbers and computer software to weight control.

Frequently information is targeted for specific audiences, such as pregnant women, school teachers, parents, medical schools or older Americans. Single copies of most publications are free. The consumer's best bet is to write the clearinghouse for its publication list.

While some clearinghouses only distribute information, others actually conduct research. the National Clearinghouse for Alcohol Information (NCALI), one of the largest, studies alcohol and alcohol abuse. A library and large data base are maintained for use by the public.

Although some clearinghouses and information centers prefer written requests for information, many encourage phone inquiries. A few have toll-free numbers.

NHIC, which receives thousands of calls a month, prefers direct contact because it allows information specialists to fine-tune questions for the best referral. The phone work adds a vital quality to clearinghouse operations, requiring employes to keep abreast of the latest findings and trends. "You never know what the next call will bring," Angle says.

But clearinghouses are not hotlines for crisis information or intervention, she cautions, and workers generally are not trained couselors. Neither should callers expect a diagnosis. Information specialist Kimberly Crumley recalls a hysterical woman who called to report that she had swallowed a leech. "At that point she needed treatment, not information." Resources

Here is a list of the major federally sponsored centers that provide information for the public as well as for health professionals. (The list is excerpted from the NHIC Healthfinder "Selected Federal Health Information Clearinghouses and Information Centers," August 1984.)

* National Clearinghouse for Alcohol Information, P.O. Box 2345, Rockville, Md. 20852; (301) 468-2600. Gathers and provides current information on alcohol-related subjects. Distributes a variety of publications on alcohol misuse. Library open to public. Office of Cancer Communications, National Cancer Institute, Cancer Information Service, Building 31, Room 10a-18, 9000 Rockville Pike, Bethesda, Md. 20205; (301) 496-5583; 800-4-CANCER. Answers requests for cancer information.

* Clearinghouse on Child Abuse and Neglect Information, P.O. Box 1182, Washington, D.C. 20013; (301) 251-5157. Collects, processes and provides information on child abuse and neglect.

* National Digestive Diseases Education and Information Clearinghouse, 1555 Wilson Blvd., Suite 700, Rosslyn, Va. 22209; (301) 496-9707. Provides information on digestive diseases. Mail inquiries preferred.

* National Clearinghouse for Drug Abuse Information, P.O. Box 416, Kensington, Md. 20795; (301) 443-6500. Collects and provides information on drug abuse. Produces informational materials on drugs, drug abuse and drug abuse prevention.

* Clearinghouse on the Handicapped, Switzer Building, Room 3119, 330 C St. SW, Washington, D.C. 20201; (202) 732-1241. Offers referrals to organizations that supply information to and about the handicapped.

* National Information Center for Handicapped Children and Youth, P.O. Box 1492, Washington, D.C. 20013. Helps parents of handicapped children, disabled adults and professionals locate services for the handicapped and information on disabling conditions.

* National Health Information Clearinghouse, P.O. Box 1133, Washington, D.C. 20013-1133; (703) 522-2590, 800-336-4797. Helps locate health information through identification of health information resources and an inquiry and referral system. Health questions are referred to appropriate health resources.

* High Blood Pressure Information Center, 120/80, National Institutes of Health, Bethesda, Md. 20205; (301) 496-1809. Provides information on the detection, diagnosis and management of high blood pressure.

* National Injury Information Clearinghouse, 5401 Westbard Ave., Room 625, Washington, D.C. 20207; (301) 492-6424. Collects and provides injury data and information relating to the causes and prevention of death, injury, and illness associated with consumer products.

* National Maternal and Child Health Clearinghouse, 3520 Prospect St. NW, Suite 1, Washington, D.C. 20057; (202) 625-8410. Provides information and publications on maternal and child health.

* National Clearinghouse for Primary Care Information, 1555 Wilson Blvd., Suite 500, Arlington, Va. 22209; (703) 522-0870. Provides information services to support the planning, development, and delivery of ambulatory health care to urban and rural areas where there are shortages of medical personnel and services. Its primary audience is health care providers who work in community health centers, but it can assist the consumer who is looking for a local community health center.

* National Rehabilitation Information Center, 4407 Eighth St. NE, Washington, D.C. 20017-2299; (202) 635-5826; (202) 635-5884 (TTY). Supplies publications and audiovisual materials on rehabilitation and assists in locating information on dates, places, names, addresses or statistics. The collection includes materials on rehabilitation relevant to all disability groups.

* Sudden Infant Death Syndrome Clearinghouse, 8294C Old Courthouse Road, Vienna, Va. 22180; (202) 625-8910. Provides information on SIDS.