SEVERAL WEEKS AGO, a group of about 20 congressional staffers met for the first of a series of seminars sponsored by the Congresswomen's Caucus. The topic of the day was Women and Prescription Drugs, and in case any people showed up not knowing this was a problem, they quickly received a fact sheet telling them that it is for an extimated 31 million women who have become dependent on drugs such as Valium and Librium.

"The most common misuse is for everyday stress," Dr. Nelson Hendler of Johns Hopkins Hospital told the seminar."This is where women fell victim more readily than men," when they walk into a general practitioner's office with a complaint and get told, 'It's all right, honey, take a little Valium and you'll feel better.' The real issue is a degree of prejudice a woman faces when she walks into a physician's office. She is two to three times more likely to get a minor tranquilizer than a man coming in with the same symptoms."

Abuse of prescription drugs is one of several issues involving health care of American women and their families that are going to be raised during this session of Congress. Two years ago, Rep. Barbara Mikulski (D-Md.) became the first woman to serve on a health subcommittee of either house in Congress -- something she refers to as a melancholy distinction -- and she has been working energetically since then to focus attention on inequities in the health care system that affect women both as consumers and as providers of care.

Her first success was passage of a bill that provides Medicaid reimbursement to certified nurse-midwives, a profession that has had a renaissance during the women's movement despite significant opposition from doctors. Her argument for including midwives in the Medicaid reimbursement system was, as she told a hearing, that it enables "consumers to make a true choice among types of service based on their own needs, preference and values. And at the same time we allow for the real possibility of controlling health care costs, not by denying needed services but by making available a wider range of cost effective services."

Mikulski also argues that not enough federal funds are spent on preventive programs -- involving such matters as nutrition and health education -- that might make costly, high-technology procedures less necessary. "If your nine-year-old is in an auto accident, we can lift him by helicopter to a shock-trauma unit and he can get the finest care available," says Mikulski aide Ann Lewis. "But if your nine-year-old is a diabetic and you need special advice on nutrition, you cannot get reimbursement for a nutritionist who could work with the family. And there are many more juvenile diabetics who have to eat school lunches and watch their friends eat snacks than there are nine-year-olds who get airlifted into emergency rooms."

Home health care for the elderly is another issue that Lewis says will be looked at and one that Mikulski raised Wednesay at the Congresswomen's Caucus lunch with President-elect Ronald Reagan.

"More than 60 percent of the elderly who are in care are cared for at home by relatives, and you and I know that means women working an eight-hour day at a job then coming home and putting in a shift as a practical nurse," Lewis said. "Let's at least provide some respite care to let them get out every so often. Maybe what we ought to be doing is rewarding people who are living up to their responsibilities and taking care of mom or Uncle Joe. Let's at least recognize what a terrible strain it is on them and let's give them some help. In his campaign literature, [Reagan] said he supported tax credits for child care of children and elderly, and she raised that as an area in which they could work together. He seemed interested."

Last year, Mikulski used budget reauthorization hearings as occasions to ask questions about what the federal government is doing to curb drug and alcohol abuse by women. She found that out of $239 million spent by the National Institute for Drug Abuse and the National Institute on Alcohol Abuse and Alcoholism very less was spent on programs that could help reduce substance abuse by women. The subcommittee voted to reauthorize the agencies for one year instead of three and directed them to look into the problems of women and substance abuse. The kinds of questions Mikulski asked before should get asked again.

And while it is too early in the session for the Congresswomen's Caucus to assess how successful it can be in focusing attention on women's health issues, it is clear that they will get some support from at least one important conservative. Rep. Robert K. Dornan (R-Calif.), the conservative abortion foe whose wife was dependent on Valium, has been "trying to sensitize others up here to the problem," according to his aide, Robert Marshall.

"There is a responsibility for government to protect people from poison," says Marshall. "When you see high Valium addiction and people drinking alcohol in combination, either the drug companies or the physicians aren't acting responsibly about this. And if they don't they just open the doors for Congress to come in."