The Food and Drug Administration on Monday announced the approval of a new contraceptive for women that prevents pregnancy for up to five years. It offers the first real alternative to barrier contraception since the introduction of the pill and the intrauterine device several decades ago.
Unlike barrier contraceptives such as the condom or diaphragm, Norplant consists of a fan-like arrangement of six silicone rubber capsules the diameter of matchsticks, but shorter, that are inserted beneath the skin of a woman’s inner arm, just above the elbow. They slowly release levonorgestrel, a progesterone-like hormone that is an active ingredient in some oral contraceptives.
Norplant is inserted in a physician’s office under a local anesthetic in a procedure that takes about 15 minutes. Fertility is restored when the rods are removed, the FDA said. The tiny rods are not visible but can be felt underneath the skin.
“This is a very important advance which will be extraordinarily useful both in the United States and abroad,” said Dr. J. Joseph Speidel, president of the Population Crisis Committee.
“It’s highly effective, lasts a long time, is reversible and doesn’t need any particular action on the part of the user--it’s something you can do once and forget,” he added. “Every time a new method is introduced, both domestic and overseas, it appeals to some potential users, so the overall total use of birth control increases. When you have more options, more people will find at least one method that is acceptable and useful for them.”
The Population Crisis Committee described the method as “very effective,” with less than one pregnancy for each 100 users each year.
Norplant was developed by the nonprofit Population Council and will be marketed by Wyeth-Ayerst Laboratories of Philadelphia. It will be available in February, a company spokesman said. The contraceptive is believed to work by inhibiting ovulation and thickening a women’s cervical mucus, which in turn blocks the passage of sperm into the uterus.
“This crowns an international scientific collaboration that spans more than 20 years of work in about 46 countries,” said George Zeidenstein, president of the Population Council. “As far as contraceptive development is concerned, we’re really in the business of options. This is a very important option that is now going to be available to people in America.”
Norplant is already approved for use in 16 countries, including Finland, Sweden, Indonesia, the Dominican Republic and Thailand.
Studies involving 55,000 women have been conducted in 44 countries, according to the Population Crisis Committee. There are 200,000 users in Indonesia alone, the committee said.
The first laboratory studies of the product began in 1966 and the earliest studies in humans began in 1968, according to the FDA. A multicenter study of more than 2,400 women was conducted at sites that included Los Angeles, San Francisco and New Brunswick, N.J.
“It is very safe and extremely effective,” said Dr. Daniel Mishell, chairman of the department of obstetrics and gynecology at USC, one of the centers where human studies were conducted.
“It’s not perfect and it’s not for everybody,” he added, listing the product’s minor inconveniences: “It takes a while to get it inserted. It involves an incision. You wear a bandage and you’re a little black and blue for a few days. And removing it takes a little bit of skill.”
But, he added, for many women--once the process is explained to them--"you put it in their arm and they really like it.”
Its major side effect is a tendency to cause irregular menstrual bleeding, the most frequent reason users have given when they have had the capsules removed. Other reported side effects include occasional headaches, mood changes, nausea and an increase in acne.
Mishell described most of the side effects as “mild.”
Moreover, Norplant does not contain estrogen, the hormone believed responsible for the most dangerous potential side effects of oral contraceptives, such as heart attacks and strokes.
Nevertheless, the FDA said that--as with oral contraceptives--women with acute liver disease, unexplained vaginal bleeding, breast cancer or blood clots in the legs, lungs or eyes should not use the product.
The FDA said that Norplant has proved more effective in women weighing less than 150 pounds and that its effectiveness could decrease in heavier women.
But Mishell said that the agency’s conclusion was based on earlier versions of the capsules which were thicker and which resulted in more dilution by the steroid in body fat before it entered the bloodstream.
“With the tubing being used now, blood levels (of the drug) are now higher and there does not seem to be a differential related to weight,” he said.
It was unclear Monday what Norplant would cost. Representatives from the company could not be reached. But Zeidenstein, of the Population Council, said he anticipates that “the price will compare very favorably with the U.S. price of oral contraceptives.”