Government Employes Insurance Co. reported yesterday that profits more than doubled for the first quarter of 1978, jumping to $20.6 million compared with $7.6 million in the same period last year.

Two major Geico affiliates also reported earnings with Government Employees Life Insurance Co. (Gelico) showing a 17 percent increase in net income and Government Employes Financial Corp. (Gefco) recording a 17 percent downturn.

Geico's earnings for the first time include the consolidated results of Criterion Insurance Co. (Crico) and Gelico. Gefco earnings are reported on an equity basis.

Geico said its net income before securities transactions increased to $13.2 million (62 cents per share), from $7.1 million (31 cents). Adding a special tax credit of $7.6 million and substracting a $200,000 loss on securities dealings produced a bottom line of $20.6 million ($1.04 per share) for the quarter ended March 31. A year ago, a $185,000 securities gain and a $2.1 million tax credit resulted in net income of $9.3 million (44 cents).

Geico said its three affiliates contributed $1.3 million to its quarterly earnings.

Geico's earnings were $798,000, (53 cents per share) compared with $968,000 (72 cents) last year. The finance company said loan volume was up 17.8 percent, from $44 million to $51 million, and gross income increased 8 percent from $8.6 million to $9.4 million.

Geico's net before investment gains was $2.1 million (47 cents per share), up 17 percent over last year's $1.8 million (41 cents). Life insurance in force totaled $2.3 billion, up 10 percent, and sales for the quarter were $39 million, up 2 percent.

B. F. Saul Real Estate Investment Trust and Federal Realty Investment Trust reported improved operating results, but Washington Real Estate Investment Trust said its profits were off.

The Saul REIT said its loss for the second quarter ended March 31 narrowed, from $2.4 million (42 cents a share) to $1.1 million (20 cents), including a $502,000 gain on the sale of property.

For the first half of the year, the Saul REIT lost $2.8 million (49 cents) compared with $4.9 million (86 cents) for the first half of 1977.

A spokesman said continued improvements in operations of properties cut the company's operating loss - before depreciation and extraordinary items - from $1.2 million in the second quarter last year to $434.000.

Federal Realty Investment Trust of Chevy Chase reported a 17 percent increase in net profits, from $408,000 (30 cents a share) to $478,000 (35 cents) for its first quarter, ended March 31.

Washington REIT reported that its net income for the quarter ended March 31 fell from $567,000 (38 cents a share) to $513,000 (34 cents) because of higher operating, administrative and interest costs.

Rental income for the Bethesda REIT, increased from $2.1 million to $2.2 million, a 5 percent improvement. A spokesman said changes in the District of Columbia rent control law permitted 10 per cent rent increases on two properties this month; similar increases at a third are planned for August.

The Rouse Co. of Columbia reported that its profits fell from $2.58 million to $1.78 million for the first three months of 1978. The company did not report earnings on a per share basis.