In the arena of political action, the people with the drive to get things done aren't always the ones with the nice personalities. "Unyielding, relentless and egotistical" is how a supporter described Margaret Sanger, though she added, "in a way that was wonderful to behold."

In " Margaret Sanger: A Life of Passion," historian Jean H. Baker chronicles the life of the driving force behind Planned Parenthood -- an activist whose single-minded ferocity was decisive in making birth-control information and, ultimately, the pill itself available to U.S. women. According to Baker, Sanger was fantastically admirable and at the same time gratingly unlikable.

But she was evidently lovable. "Never be ashamed of passion," Sanger advised young women in her 1926 "Happiness in Marriage."

Apparently she was. "One should always be in a state of love," she was insisting in her 70s. She had two husbands, and I lost count of what Baker calls her "catalog of lovers."

The arc of Sanger's life is, for a reader, extremely satisfying. On the first page, Baker calls her "one of those rare, signal reformers who live long enough to celebrate the acceptance of their cause," and later she elaborates: "Sanger's life spanned -- from her birth in 1879, six years after the passage of the Comstock law, to 1966 and its overturning -- the entire judicial history of contraception's legal course."

The law she's referring to was named for Anthony Comstock, a fundamentalist who arrived in New York from Connecticut shortly after the Civil War and, horrified by what he found going on there ("lust -- the boon companion of all other crimes"), began a campaign against all things sexual. In 1873, he cowed a Congress exhausted and demoralized by the scandals of the Grant administration into enacting the "Suppression of Trade in and Circulation of Obscene Literature and Articles of Immoral Use."

It was a draconian law that criminalized not only erotica and condoms but also all information relating to birth control, including the provision of it by doctors -- under any circumstances.

Sanger was arrested in August 1914 for distributing copies of her pro-contraception magazine, The Woman Rebel, and again in 1916 for opening a clinic in Brownsville, Brooklyn, that dispersed the forbidden knowledge. (It was the progenitor of today's 800 Planned Parenthood clinics.) But she always knew how to profit from her setbacks. The 30 days she spent in jail, Baker writes, made her "birth control's martyr."

Sanger would be amazed to find out how rabid the opposition to women's sexual freedom remains a half-century after her death. But she might like knowing that the current chairman of the International Planned Parenthood Council is her grandson, Alexander Sanger.