New Concern for the Unborn

In one case out of 25, even in advanced Western countries, a baby is born with a physical or chemical defect that may doom him to an early death or a lifetime of illness. Until a few years ago it was assumed that little or nothing could be done about most of these misfortunes. Then, in 1958, the National Foundation-March of Dimes, having conquered polio, turned its attention and resources to the problem of birth defects. Last week in The Hague, at the Foundation's third birth defects conference of the decade, 975 scientists from 35 countries listened to 194 progress reports and some clarion calls for a more massive offensive.

The conference provided fresh evidence of a radical shift in medical emphasis from treatment of adult ills to the health of the child, the infant and even the embryo. But medical researchers do not intend to stop even there. They are also considering the health of the mother at the time of conception, the health of both parents before conception, and even the health of the mother's mother at the time she conceived.

Broad Categories. As honorary president of The Hague meeting, March of Dimes' President Basil O'Connor acclaimed "the beginnings of achievement in a worldwide, concerted effort of science--the first in history--to improve the quality of human life at birth." But he went on to warn: "This means that you must also be prepared to protect the human heritage from a possible proliferation of defective genes. It is humane to save the lives of sick children. It is neither humane nor morally defensible to permit the cause of their illness to be perpetuated if that can be prevented."

The term congenital malformations covers all three broad categories of defects present at birth:

> Inherited. Something goes wrong either in one or more of the genes themselves, or in the chromosome packages in which the genes are arranged.

> Accidental. At the time of conception or shortly thereafter, cell division goes awry, causing such conditions as abnormal twins.

>Environmental. There are unfavorable factors in the embryo's uterine surroundings--some nutritional deficiency in the mother, drugs in her bloodstream crossing the placental barrier, or viruses infecting both mother and fetus.

Mongolism, or Down's syndrome, probably the most common major congenital malformation, occurs once in every 600 births and can be caused by either inherited or environmental factors. Both severe heart defects, next in frequency with an incidence of one in 700, and cleft palate, one in 800, can result from any of the factors.

That geneticists still have much to learn was shown by the disagreement over the importance and effects of an extra Y chromosome in males. Jerome Lejeune held fast to his controversial contention that this chromosomal aberration is closely associated with criminality. Delinquency, he said, is 20 times as common among men with XYY defects as among those with normal chromosome endowment.

Whether a whole chromosome or a single gene or a group of genes is responsible, genetic defects can affect every part of the human body and the mind. Dr. Victor McKusick of Johns Hopkins, the world's leading expert on dwarfism, supplied a forbidding list: abnormalities of the skeleton, of the innumerable enzyme systems, of the nervous system, of blood cells, both red and white, of clotting mechanisms, of the hormone systems, of the kidneys, of the intestinal tract, and of the muscles. The eyes and ears are also susceptible--there are about 40 varieties of hereditary deafness, said McKusick --and so is the skin.

For the present, the international assembly offered more hope for prevention and improved treatment than cure of birth defects. One preventive technique is amniocentesis--inserting a needle through the pregnant woman's abdomen, into the amniotic sac, and withdrawing fluid for analysis of the cells shed by the embryo. For the apparently normal woman this would never be recommended. But it is a boon for the woman with a history of pregnancy mishaps, or one whose family is known to harbor inheritable defects. At Children's Memorial Hospital in Chicago, Dr. Henry L. Nadler reported, his department has "managed" 150 pregnancies on the basis of such cell studies. In 14 cases, abortion was recommended, and in 13 cases the abortion was carried out. In the 14th, the mother of one mongoloid child said she would rather have another mongol than an abortion--and she did. In the other 136 cases, no abortion was recommended, and all the babies born were normal. This procedure, Nadler emphasized, neither encourages abortions nor increases their incidence. What it does is enable couples capable of transmitting genetic defects who desperately want normal children to have almost the same chance of having them as couples with no such problems.

Risks of Age. More and more defects, especially those resulting from lack of an enzyme, are now being detected. In most cases, the only "remedy" is abortion. But sometimes it may be possible to contain an enzyme deficiency by altering the mother's diet. If the embryo is developing unnaturally because of faulty nutrition, it even may be possible to inject nutrients into the amniotic fluid, which the fetus absorbs.

A factor over which would-be parents have some control, provided they start to exercise it early enough, is the age of the ovum at the time of conception. Rockefeller University's Dr. E. Witschi reported that studies in several animal species show that an old or "stale" egg is especially likely, if fertilized, to result in the birth of a defective baby. In humans, it is known that the risk of having a mongoloid, for instance, increases from one in 2,000 births for a woman at age 25 to one in 50 at age 45. For a woman's ova, unlike her husband's sperm, are not manufactured continuously so that they are always fresh, but are laid down in a sort of pre-egg form while she is still in her mother's womb, or shortly after birth. This explains why the mother's health, at conception and during pregnancy, may be important a generation later. Therefore, West Germany's Dr. Widukind Lenz concluded, "the present trend toward earlier sexual maturity, earlier marriage and earlier reproduction is biologically favorable."

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