The New England Journal of Medicine is not what you would call a trendy magazine. There are no pictures of couples jogging. No debates on supply-side economics. No editorials on Middle East politics.

The scientific articles tend to attract one or two letters to the editor, rather sedate rebuttals on subjects like Cyproheptadine and Mineralocorticoid Receptors. That sort of thing.

But last week's "Correspondence" section fairly blistered with arguments about the heated social issue that has paraded through these pages in medical clothing: "When to Have Chilldren."

The Journal entered the whole when-to- have-children debate last February by publishing French research on women who were trying to conceive through artificial insemination. It pointed to a "slight but significant" drop in the number of women over 30 who got pregnant within one year.

Since it has been generally assumed that female fertility remained constant until 35, the French study was news. It seemed to fine-tune the biological clock a bit.

But the careful, limited report was accompanied by an editorial that leapt to a conclusion about how women should plan their lives: "Perhaps the third decade should be devoted to childbearing and the fourth to career development."

All of this gained something (ominous) in the translation to the public over the news wires: "New findings on fertility suggest that working women who want babies should have them during their twenties instead of waiting until they have established their careers."

Well. The whole flap hit young women, single women, not-yet-childbearing women in a particularly vulnerable spot. Here were more statistics for their arsenal of anxiety. A generation of women trying to factor in work, marriage and children was told that the biological factor was changing.

In the following months, we were treated to occasional stories headlined, "Women Reconsider Childbearing Over Thirty," and to features about women calling their doctors in a state somewhat between concern and panic.

Last week's letters cap the whole Medical Media Event. There were, first of all, scientific rebuttals. Three correspondents pointed out that the French research could simply mean that older women took a little longer to become pregnant.

Then there were the social rebuttals. Two Wellesley researchers, Kathy Weingarten and Pamela Daniels, noted that, in their study, "Without exception couples who had their first child in their early twenties -- within one or two years of early marriage -- later wished they had delayed parenthood in order first to develop as individuals and as couples."

A Pittsburgh correspondent whacked the editorial suggestion of babies first, careers second, with one sentence: "How many medical schools would be willing to accept a student of 30 with two children?"

All of this was a good reminder that options of women in their twenties and thirties often felt like conflicts. Research has turned the screws. Now you could: (1) Be a "premature" mother in your early twenties trying to raise a career at the same time or facing a reentry struggle in your thirties. (2) Develop a career in your twenties and increase the infertility risk in your thirties. (3) Arrange a match between marriage, work and maternity that all coalesces in one magical mystery moment on your 29th birthday.

It is hard to remember that this commotion was started by one qualified and debated scientific study of modest fertility changes in some 2,000 artificially inseminated French women.

The media had turned up the volume on the alarm. But I think that the intense reaction to this news suggests how women view their own newfound life patterns, choices and decisions. The pattern feels fragile, easily shattered by a single statistic.

The whole event may say more about our psychology than our fertility. The simple desire for a life that includes work, marriage and children is still described as "wanting to have it all." Many wonder if this desire isn't a kind of hubris that excites the envy of ancient gods. The gods of fertility.

In the letters column, the original editorial writers backstepped: "We certainly do not suggest that couples should make decisions on childbearing solely on the basis of the women's age or data provided by one study." This time it's safe to take the doctors' advice.

Copyright (c) 1982, The Boston Globe Newspaper Company