"Many issues of equality between men and women start in the bedroom," says author Bruce Stokes. "And when it comes to who controls fertility, men are the forgotten sexual partner.

"Male contraceptives are treated as second-class birth-control methods," summarizes Stokes, whose Worldwatch Institute study on "Men and Family Planning" was released Saturday.

"People will discuss the pill and the diaphragm at a dinner party, but they make jokes about the condom.

"Until recently there has been little research into new male methods of birth control. Sex education is usually oriented toward women -- so men often have a poor understanding of anatomy and contraception -- and few family-planning programs target men as clients."

At the root of the problem is a "macho-man" stereotype that is "half myth and half reality," says Stokes, who has a degree in international studies and is a senior researcher at Worldwatch, a nonprofit institute funded by U.N. organizations and private foundations to focus attention on global problems.

The "macho myth," he says, paints the typical man as unwilling to use birth control because he associates fertility with virility and is more concerned with his own pleasure than with the health and well-being of his partner.

"But male attitudes don't fit this simplistic stereotype. Recent studies indicate that men have much more interest in family planning and willingness to practice it than they are given credit for."

But despite professed concern about contraception, Stokes notes that most men "unfortunately don't practice it.

"In the industrial world, men frequently use the availability of female contraceptives as an excuse for not using birth control themselves. In the Third World, some men still insist on having sole right to decide whether and when to have a child, and many deny their wives access to contraception because they fear it will encourage promiscuity.

"And everywhere there are men who oppose birth control and women's changing roles in society because it seems to leave them with a diminished position in the family."

This seeming conflict between what men say and what men do, Stokes says, results in a self-perpetuating cycle: Men have negative attitudes toward contraception, so no money is spent to improve or to make more available male contraception, so men have negative attitudes toward contraception. .

As one sign of men's interest in male contraception, he points to the increased use of condoms in the United States. "Part of this increase is due to more teens having sex," he says, "and many use condoms. Also, women's increasing concern about the pill and IUD is pushing many men to use the condom.

"Then there's the growing concern about sexually-transmitted diseases. Condoms are the only effective way to guard against them."

But condoms, he says, "are considered a backward means of contraception. They're not technologically sophisticated enough for a pill-popping society. They're more effective, though, than they're generally credited to be -- 90 percent effective as compared with 90 to 96 percent for the pill.

"But we've rarely improved it in decades. In 1977, $10 million was spent on testing the effectiveness of the IUD and the pill, but not a cent was spent on condoms."

The most dramatic change in male contraceptive use in the last decade has been the threefold increase in the number of vasectomies. "Some experts," says Stokes, "predict as many as 30 percent of the Baby Boom men will have vasectomies when they complete their families.

"There's a growing awareness that men want to share contraceptive responsibility, and many apparently feel that if the woman took the risks earlier on, it will be their turn later. If an inexpensive and easy means of reversing vasectomies can be developed, the number of men willing to have the operation could soar."

As for the male pill, Stokes says, "It's been 'just around the corner' for a couple of years. Some experts say it will be technically feasible by 1990. It is more likely one will be in use by the end of the century."

Contraceptive researchers, says Stokes, contend that there is little understanding of the male reproductive system. "They claim halting male sperm production is biologically more difficult than halting a woman's monthly ovulation."

"Researchers," he adds, "who were usually men, have been only too willing to experiment with women's bodies and haven't shown the same willingness to experiment with men's bodies."

Putting more money and effort into improving, developing and distributing male contraception is "a must," says Stokes. "Society also needs to hold men more accountable for the results of their sexual activity -- the children they father.

"Three out of four men who owe child support don't pay it. Men need economic incentive to be involved in contraception. And society needs to encourage men to play a more responsible role in the family, not only through accessibility to birth-control services -- perhaps through couple's clinics -- but in paternity leave and shortened workweeks for fathers of young children.

"It's not a question of men controlling fertility versus women controlling fertility. It's a question of sharing."

In ongoing relationships, says Stokes, "building the trust to share this burden will be an integral part of creating a new role for men in family planning."