The most severe case of French Boredom on record must be that of the heroine of "Get Out Your Handkerchiefs," French director Bertrand Blier's film, which must be classified as a sort-of-comedy, because it certainly isn't a tear-jerker.

French Boredom, the widespread malady in wich such writers as Francoise Sagan have specialized, is a phenomon that would be called contentment in amy other country. The French try to dress it up by calling it ennui , but it's still the plain old boredom of the Mommy-I-don't-feel-like-doing-anything variety.

The French version generally strikes people who have everything they want. The chief symptom is a vacant look from eyes with kohi-rimmed lower lids. Like wealthy TB victims of an earlier time, the sufferers must rest in luxurious quarers they find stultifying; French Boredom patients are confined to beds and cafes.

The poor lady in this film is in such bad shape from having a comfortable home and devoted husband that her husband is desperate to cure her. A flaw in the film is, however, tht neither he nor the filmmaker has made a proper diagnosis. Both assume that the heroine is suffering from Empty Womb, a once-terrifying disease that, unbeknownst to them, was wiped out in the 1950s by the enlightment of new feminism.

Proceeding on his error, the husband enlists help from passing strangers. Since he has not succeeded in impregnating her, he keeps hailing passing strangers to do the job. One man so earnestly sympathizes with him as to become an auxiliary husband, and the two of them are frantically on the lookout for more help. French husbands and lovers, judging from this and the new film "Woman at Her Window," in which such a pair help a woman get and save the man she really wants, are exceedingly generous.

Carole Lare plays the woman with such convincing emptiness that it seems reckless of her two men not to test the hypothesis that she might be dead. Of course that pair, while played considerably more actively by Gerard Depardieu and Patrick Dewaere, do not themselves seem particularly alert.

As it turns out, what it takes to impregnate this woman is something slightly more kinky than they had imagined, namely a solemn know-it-all of a 13-year-old boy named Christian.

Maybe this means she has found Christ. Qui sait ? The French have mysterious illnesses.