Gynecology: The Pills: More Effective, And More of Them

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Last week, with newly announced approval by the Food and Drug Administration of three more oral contraceptives, American women and their doctors had a total of six to choose from.

By federal law, all are available on prescription only. They are:

> Enovid, the longest on the market, made by Chicago's G. D. Searle & Co. in large-dose tablets.

> Enovid-E, just released, a miniaturized version of Enovid.

> Ortho-Novum (Johnson & Johnson's subsidiary, Ortho Pharmaceutical Corp.), on the market since 1962 in a full-dose tablet.

> Ortho-Novum-2, a reduced-dose form on sale since last fall.

— Norlestrin (Detroit's Parke, Davis & Co.), a new, small-dose tablet. >Norinyl (Syntex Laboratories, Inc.), another new, small-dose pill.

Sales of the pills have been increasing steadily around the world, and especially in the U.S., where the cost (about $4 for a month's supply of the larger pills, $2.25 for the smaller) is less of a deterrent. But as with all new and potent drugs, many questions arise: Just what are the pills? How do they work? Are they certain? Are they safe? What are the disadvantages and discomforts of using them? How long can a woman go on taking them? Could they cause cancer or deform babies in the womb?

The answers, in nearly every case, are reassuring.

Giant Yams. A woman of childbearing age has a menstrual cycle of 23 to 39 days, but the average is close to 28 days, and this figure is always used by doctors prescribing the pills. It is a safe choice because even women who have had different cycles usually convert to a 28-day cycle while on the pills.

Within five days after her cycle starts (see chart), a woman's pituitary gland begins producing the follicle-stimulating hormone FSH, which travels through the blood to the ovaries, which contain about 300,000 follicles. FSH starts a few of these on a growth process that results in the production of one ovum (egg). Around the 14th day of the cycle, ovulation occurs: the follicle releases the ovum, which travels down the Fallopian tube toward the uterus. If it encounters a live spermatozoon on the way, or soon after its arrival, the ovum will be fertilized.

Nature has an automatic regulator to prevent the too-rapid production of another, regardless of whether the ovum is fertilized or not, which might lead to overlapping pregnancies. After any one ovum is released, the body starts producing progesterone. Sometimes called "nature's contraceptive," this hormone serves mainly to prevent the ripening of another ovum until the next cycle starts.

The natural progesterone secreted in women's glands is not very potent when taken by mouth. But since 1951, laboratory experts have been making chemically related substances, now known as progestins, from such unlikely raw materials as the root of the Mexican giant yam. Some of these synthetics are far more potent than natural progesterone—at least for preventing ovulation. The two best known are norethynodrel, the main ingredient in Enovid, and norethindrone, used in the other contraceptive pills now marketed in the U.S. and by various manufacturers around the world.