In a first-ever move to curb skyrocketing medical and hospital costs, the government will encourage its own employes and retirees -- members of the nation's largest "company" insurance plan -- to shop around for health insurance.

The major comparison-shopping drive begins Nov. 17. It involves more than 8 million civil servants, family members and retirees. It centers around a $400 million health insurance premium jump coming this January.

Workers and retirees will have the period between Nov. 17 and Dec. 7 as an "open season" to pick the best insurance deal for themselves for the coming year. Decisions they make will impact on prices doctors and hospitals charge other Americans, and the insurance packages that firms offer nonfederal subscribers in the future.

The average government insurance premium increase for 1980 will be 10 percent. Although Uncle Sam will absorb $250 million of the $400 million total boost, rates paid will have a substantial effect on types of coverage and costs for medical care in the private sector.

Because of the short-time frame (and the bewildering array of 106 plans in the federal program) most employes lack the time or expertise to shop all markets. During the open season period most people stick with the plan they have.

But Health, Education and Welfare, which has been pushing Health Maintenance Organization-type coverage, has come up with a shopper's guide. Civil servants can use it to compare benefits they get under the two largest carriers in the program, and the four HMOs here in the federal plan.

Most federal workers are covered by Blue Cross-Blue Shield or Aetna. Washington's 380,000 civil servants have the choice of a number of plans, including union-backed plans, as well as the four HMOs.

HEW's Office of Health Maintenance Organizations, has printed up 300,000 copies of the local comparison shoppers guide. They will be available at agency personnel offices shortly. (A few copies are available now at HEW by calling 443-2300).

Beginning in January when premiums go up, the government will pay $30.61 for high-option, family type coverage, biweekly for each employe.

Here are rates employes will pay every two weeks for high-option, family coverage plans surveyed by HEW: Blue Cross-Blue Shield: $26.87. Aetna: $12.56 George Washington U. HMO: $28.75 GEORGETOWN U. HMO: $31.75 Health-Plus HMO: $35.22 Group Health Association: $19.81

HEW's brochure doesn't cover other plans, nor does it deal with cost. Rather, it advises employes to be "careful consumers" shopping for the plan that best fits their needs, at lowest cost. The idea is to force the health carriers, through consumer pressure and use, into making the best deals, at the lowest costs.

The benefit comparisons are too detailed to be outlined here, but the HEW fact sheet shows that employes can save significant amounts of money by shopping for insurance. Although premiums vary, as shown above, benefits offered by the insurance carriers often are identical.

For example the four local HMOs outlined by the HEW comparision guide offer 100 percent coverage, with no time limit, for in-patient hospital care. Blue Cross-Blue Shield pays 100 percent of the first $2,000 in costs, and 80 percent thereafter, according to HEW. Aetna pays 100 percent for up to 365 days, and 80 percent thereafter.

Payments for outpatient care differ between the HMOs and the two major plans. The HMOs have some limits on hospitals that may be used in nonemergencies whereas the two major carriers do not.

Personnel offices should be getting copies of the brochures shortly. People ought to take a look at them -- as well as other plans available -- before picking a 1980 insurance plan.