BOOK REVIEW : Where Ordinary Miracles Are a Breeze : ORDINARY MIRACLES <i> By Linda Crew</i> ; William Morrow $20; 288 pages

Betsy Bonden is standing next to the frozen corn dogs in a rural Oregon supermarket when her husband announces that his doctor has diagnosed a hernia. Betsy is not particularly sympathetic: “ ‘Gil, that’s great!’ ” she says, a reaction that leaves Gil perplexed.

The mystery is short-lived, however, for Betsy quickly explains that medical insurance would undoubtedly pay for a hernia operation . . . and in a twofer, also for a fertility operation that could be performed simultaneously at the insurance company’s expense.

The above is one of a number of amusing scenes in “Ordinary Miracles,” the first grown-up novel by Linda Crews, a writer of young-adult titles. You’d be able to guess Crew’s writing background even if you skipped the novel’s biographical note: There’s a breeziness to “Ordinary Miracles,” a skillful skimming of surfaces, that both beguiles and irritates.

Whether Betsy is fending off the overtures of an amorous construction worker, or wailing at the realization that she has failed to become pregnant once again, or barely suppressing the urge to buy infant paraphernalia, she always shows spunk--and spunk, as anyone who has seen the “Mary Tyler Moore Show” will remember, is not a trait of universal appeal.

Growing up, Betsy never thought of herself as wanting to have children--that job had already been staked out by her younger sister, Stephanie. As Betsy told her father, with regard to her college education, “wouldn’t it be a big waste to spend so much and then have me turn into some dumb baby machine?”

But now, in her 30s, Betsy has changed her mind, only to find herself unable to get pregnant. The infertility may be hers or Gil’s, but whatever its source, it drives Betsy crazy. The Bondens eventually turn to medical treatment for their predicament, first for Betsy, and she’s fully cognizant that “half the women win big and the other half go bankrupt and psychotic hoping to.”

Do Betsy and Gil end up having a healthy baby? You might as well ask who’s buried in Grant’s tomb, or whether the Pope is Polish. The obvious resolution isn’t bothersome, though, because this sort of novel is supposed to be uplifting; more problematic is Crew’s failure to leaven it with developed subplots.

There are only so many ways of expressing the ups-and-downs endured by would-be parents when their attempts to beget a child prove difficult, and that leaves Crews with numerous scenes carrying the same emotional freight.

She writes about this roller coaster ride with humor and some wit, but often you feel like you’re waiting for the other shoe to drop. Of course one of Betsy’s supposedly infertile acquaintances will get pregnant first, and so will both Stephanie and Laura, Betsy’s stuck-up cousin who for years insisted she’d never have kids.

Two things keep us interested in Betsy: her close-but-nettled relationship with her family, and the half-tender, half-sardonic one-liners Crews has Betsy, and occasionally Gil, dispense. Why have a traditional wedding? Because the photographs “won’t be so embarrassing later.”

Why not adopt a child, as Gil suggests?

Because his easy attitude toward adoption “only made those genes seem to me that much more worthy of being reproduced.” How does a husband comfort a wife who tortures herself by saying if he’d married his old girlfriend, he’d have children by now? By saying, as Gil does, “If I married her, I’d have a custody battle by now.”

“Ordinary Miracles,” in a word, is heartwarming, which is shorthand for saying that Crew’s sentimentality is effective enough, at times, to overcome critical judgment. To put it another way: When Lou Grant said he hated Mary Richards’ spunk, we all know, deep down, he didn’t really mean it.