The pill? "I wouldn't touch the stuff," says Marian Diamond, 50, who is a mother of four. "In my house we don't even take aspirin."

Marian Diamond's strong views on medication are shaped by something more than personal preference. She is also Dr. Diamond, an associate dean and professor of physiology and anatomy at the University of California. Her special field is the brain, and particularly, the potentially harmful side effects of birth-control pills. "Right now more than 50 million women are taking ovarian hormones," she reports. "We know what they do to our reproductive system. We've also seen a relationship between their use and the rise of blood clots. Now we have evidence that they may retard the growth of the brain. We've reached the point where we should start to evaluate the effect of the pill on our entire bodies." But, she acknowledges, "it may be 20 years before we have the definitive word on the pill. Do we sit around and wait?"

Not if Dr. Diamond can help it. To start finding answers now, she has organized the first major national conference for the layman on the pill April 7 to 8 at Berkeley. Ironically, in assembling her panel of a dozen experts, she discovered that "the best known authorities on the female body are all men." Rather than be "a majority of one," she found some women speakers.

For Diamond, such odds are familiar. The youngest in a family of six children, she grew up in Glendale, Calif. At an age when other little girls were playing with dolls, she was bringing home dead birds for dissection. Even her doctor-father thought her passion for science peculiar. "He only wanted his daughters to marry," sighs Marian.

Though she breezed through a biology degree in 1948, her application to medical school was rejected. "It nearly devastated me," she recalls, "but I decided to fight" by going on to a Ph.D. in anatomy. At the time she was Berkeley's only woman grad student in her subject.

One colleague who accepted her as an equal (they split chocolate milkshakes) was physicist Richard Diamond. They married, studied at Harvard, moved to Cornell and reared a family of two daughters and two sons.

Marian Diamond returned to Berkeley and became a member of the faculty in 1965. Today, she is one of 33 women there with full professor rank (versus about 900 men). Among her findings in recent experiments with rats is that the brain does not stop growing in an older animal if sufficiently stimulated. "This may mean that human beings can be mentally alert at any age, as long as we keep using our brains," she reports. "How's that for a beautiful finding?"