You snooze . . .

Meg WOLITZER’S 1982 debut novel, “Sleepwalking,” focused on the painful transition to adulthood of three college women who share an unhealthy fascination with suicidal female poets. Her eighth and newest, “The Ten-Year Nap,” is an exploration of the somnolence that overtakes the lives of four middle-aged New York City mothers who have opted out of careers to stay home with their children. Wolitzer’s titles may evoke images of slumber, but this penetrating prober of family dynamics has hardly been dozing these last 26 years.

After her string of early novels exploring unconventional relationships and intense female friendships, Wolitzer’s last two books were a wake-up call to readers, making it clear that she’s more than just a pillow-fighter on gender issues. “The Wife” (2003) was a startling story about a 1950s marriage in which a talented woman took the role of helpmate to extremes, ghostwriting her less-talented husband’s prizewinning books. In “The Position” (2005), the children of the authors of a “Joy of Sex”-type manual cope with fallout from the sexual revolution. The underlying theme of both is an idea expressed by a character in the new novel: that women have been given “a raw deal in society.”

“The Ten-Year Nap” is more topical, focusing on the so-called opt-out generation -- the much-discussed phenomenon of educated professionals (often daughters of feminists who fought for the right to work outside the home) who quit their jobs after having children. Is this the perk of women with wealthy husbands or a self-inflicted raw deal?

Because so many have spent time tossing and turning in this feminist hotbed, including New York Times columnist Lisa Belkin, who has made women’s issues her focus, the issues feel somewhat rumpled, less than fresh. Wolitzer tries mightily to add starch. Her writing abounds with lovely images that capture her characters’ lives -- the “spackling of peanut butter onto bread” or coaxing “the last of the sunblock from the snouts of bottles.” But “The Ten-Year Nap” often sags like an old mattress with the weight of its characters’ earnest discussions about ambition, aging and societal expectations.

Three of the novel’s protagonists are friends with 10-year-old sons in the same tony all-male Upper East Side private school. It’s the sort of place where fourth-graders learn Latin, a world skewered in the movie “The Nanny Diaries” and Ayelet Waldman’s book “Love and Other Impossible Pursuits.” Wolitzer’s goal, however, is understanding, not satire, and her focus isn’t hyper-parenting: It’s what the absence of purpose does to educated, formerly ambitious women.

Amy Lamb, a former trusts and estates lawyer, lives in a luxury high-rise apartment that she and her husband can barely afford. He is an associate at the law firm where they met, never having made partner. Unlike her mother, who liberated herself from the chains of domesticity in the 1970s to write historical novels, Amy “had never been deeply in love with her work.” So when her son was born, “she willingly exchanged the law firm for the long and astonishing inhalation of motherhood, which itself, over time, had gradually been exhaled.”

Now that her son is less needy, Amy realizes that she should fill her days more meaningfully than with coffee klatches and yoga. Despite tight finances, she considers “some formal volunteer position.” It takes very loud alarms to wake her up to the fact that she needs a paying job. The novel charts her “long and very slow odyssey toward work” -- one that readers may find too long and too slow.

Wolitzer’s characters know they live in a privileged, insular world: It’s one more thing they feel bad about. Flashbacks to their mothers -- a 1972 consciousness-raising group, the steamy kitchen of a restaurant in San Francisco’s Chinatown -- reveal how far they’ve come. “Excellence unfulfilled” and its attendant disappointment plague these women. Only wealthy, brilliant math whiz Karen Yip is content with making sure her twins’ and investment-banker husband’s days run smoothly. “Does everyone always have to ‘do’ something? Can’t they just enjoy their lives?” Karen asks.

Amy’s college friend Jill, voted most promising in prep school, is dismayed by her failures to finish her dissertation, conceive a child and nurture the Russian daughter she eventually adopts. Jill moves to a leafy suburb in “a palpable attempt to create an alternate, tolerable world” after Sept. 11, whose specter haunts all four women, fueling their urgency to imbue their lives with meaning.

Wolitzer’s bias is readily apparent, beginning with her pejorative title: Ten years is a long time to snooze. She’s more patient with her characters than readers are likely to be, but her depiction of these women, their husbands and marriages makes it clear -- she finds opting out a dangerous reversion.

In fact, the novel, like poet Donald Hall’s memoir “Life Work,” is a passionate paean to the redeeming power of purposeful occupation. Wolitzer, who has never stopped writing while rearing two children, emphasizes that “work could pave your entire life with meaning.” Or, as Amy’s feminist mother puts it, “Work is anti-death.”

“The Ten-Year Nap” may not be as taut and fresh as Wolitzer’s last two novels, but there’s enough between the covers to remind us that her writing is worth staying awake for.