An expected sight in most delivery rooms these days is the cool, collected father-to-be, sensitively and competently coaching his sweating, writhing partner through labor and birth. The labor coach's job is to calm and encourage the frightened and weary mother-to-be. The place for emotion on his part is not until the moment of birth, when he is finally allowed his tears of joy and relief.

But health care professionals sometimes ignore the fact that birth can be frightening and upsetting for many men, a nursing professor told a group of registered nurses last week. The blanket assumption that serving as labor coach is the best way for a man to experience the birth of his child, she said, is sometimes unfair and unrealistic.

"Some men are scared stiff," said Katharyn Antle May, associate professor in the Department of Family Health Care Nursing at the University of California at San Francisco. May, who has been studying and working with fathers since 1977, spoke during a four-day convention, sponsored by the American Journal of Maternal/Child Nursing (MCM) at the Baltimore Convention Center. About 1,000 registered nurses from around the country attended the convention, which focused on a broad range of issues in obstetrics, neonatology and pediatrics.

"Do you all remember the first time you went into a labor-delivery room as students?" May said. "Do you remember the sheer terror?" She asked the nurses to imagine how much more frightening that first experience would have been if the person in pain had been their spouse.

Even childbirth education classes aren't always adequate preparation, May said. Those classes usually last from four to six weeks, whereas "good labor-delivery nurses are trained for years."

In many cases it is desirable for the father to be in the delivery room, she said, but each couple should be treated as a unique entity. She encouraged the nurses at the session, most of them female, to become more sensitive to the needs of men during pregnancy and birth.

"Nurses need to encourage men to . . . talk about what scares them," she said.

"New dads are usually the moms' lifeline after the birth," May said during an interview later. "If his needs aren't met, then he's going to be less able to meet hers later."

May said she had had some experience with Vietnam veterans who had difficulty during their children's births. One man, she said, had helped a Vietnamese women give birth in a battle zone, only to see her and the baby gunned down after she stood up and walked away.

"He had a flashback during his wife's labor and had to be wheeled out in a wheelchair."

May said it is often the health care professionals, not the mothers-to-be, who erroneously assume that active participation in classes, birth and other activities related to pregnancy is desirable for all expectant fathers.

"That is a major value statement. It depends on a lot of factors that are established well before pregnancy," she said. "Usually a spouse can predict what her husband is going to be like during pregnancy and birth and can accept it."

May listed some other myths about fathers and births:

*Men don't get involved until the third trimester. In fact, the emotional impact of a pregnancy begins much earlier, she said, adding she would like to see men included in more early pregnancy classes.

*Men are involved only on an emotional level. Up to 50 percent of expectant fathers experience physical pregnancy symptoms, she said, and "that may be a healthy sign . . . It may be a way of getting in touch with the emotional aspects. She said the men who do experience the sympathetic pregnancy symptoms -- called the couvade syndrome -- tend to be those who have more androgynous characteristics, and also tend to be more nurturing after the birth.

*The father's presence at birth causes shorter labor and a decreased need for anesthesia. This popular notion can't be proven, since preexisting factors, such as both parents' motivation, personality and readiness for pregnancy may contribute more to a trouble-free birth.

*The father's participation leads to better bonding with the infant. "The data just isn't there," May said. In fact, one study even showed better father participation among those who weren't present at the delivery.

Hospitals should allow a third person in the delivery room, she said, so even if the expectant couple decides the father isn't the best person to be the labor coach, he could still be there.

May also described the results of interviews she did recently with 46 men whose partners had undergone cesarean sections. About half those fathers were excluded from the delivery room.

She discovered that, for the most part, they weren't angry that the cesareans had been done. Their "real issues," she said, "were around being excluded."

Several of the fathers, even months later, cried during her two-hour interviews with them. "They felt angry, depressed, guilty," she said. "They felt like they failed their partners.

"Someone is giving them that perception, and I'm afraid that someone is us. We've done our job too well. Now we have men believing they can prevent cesareans."

Most of the time, May said, anesthesiologists, not obstetricians, run the show in a delivery room. One commmon reason given for some men to be excluded from cesareans is that the mother is being put under a general anesthesia. "The perception is that because she's under . . . the mother doesn't need the father there."

One father, who was terribly upset about being excluded, told May, " 'Someone needed to be there to welcome the baby.' "

Other reasons given for excluding fathers are that fathers might cause disruptions or that their presence might lead to malpractice suits. "I know of few documented problems with fathers in the delivery room." And as for the increased risk of malpractice suits, May said she believes the opposite is true if doctors are explicit and open with the fathers, instead of exhibiting a "We know what's best" attitude. MM ay's presentation was one of about 70 hour-long sessions covered M topics including: care of premature infants; the changing role of the family; AIDS in infants, children and pregnant women; child behavior; sexual abuse; organ donations; and how to deal with the emotional needs of dying children.

Ruth Wilf, director of a nurse-midwifery service in Turnersville, N.J., spoke on "Once a Cesarean, Always a Cesarean?"

Most of the time it is a fallacy that women who have had a cesarean can never have a normal vaginal delivery, Wilf said during an interview.

Who is a good candidate? "Almost anyone," Wilf said. If a woman has the desire to try a vaginal delivery and has a horizontal cesarean incision (which damages fewer muscle fibers in the uterus), then "she should try it," Wilf said.

Her labor "is a special situation and should be monitored carefully," Wilf said, but in one group of 84 women who were good candidates, 78.6 percent had sucessful vaginal deliveries.

Vaginal delivery after a cesarean has become much more common in the last five years, Wilf said. Her goal in the next five years, she said, is for "each labor to be evaluated in terms of each labor" -- not by what happened during a previous delivery. She also hopes to see an end to the situation where parents must search "far and wide" for a doctor who is willing to attempt a normal delivery after cesarean.