Amanda Gerten (letters, April 2) misinterprets Guttmacher data, leading her to falsely state that contraceptive use somehow leads to more abortions. I'd like to set the record straight.The fact is that contraception is highly effective. The two-thirds of women who use contraception consistently and correctly account for only 5 percent of all unintended pregnancies. In contrast, the much smaller groups who use contraception but do so inconsistently (for instance because they forget to take their pills) and those who don't use contraception at all make up the lion's share (95 percent) of unintended pregnancies in the United States.This statistic shows that we need to make it easier for women to use the contraceptive method that best meets their needs. One barrier to more effective contraceptive use is cost. Even for women with private health insurance, out-of-pocket costs for the pill can reach hundreds of dollars annually. The most effective methods, like the IUD and the implant, can be even more expensive—and all up-front.Contraceptive coverage without additional cost-sharing removes cost as a deterrent to a woman's choice of contraceptive method. Studies bear this out: When a California health insurer eliminated cost-sharing for long-acting IUDs, implants and injectables, enrollees' use of these methods increased substantially—and their risk of contraceptive failure plummeted.Natural family planning, the only method sanctioned by the Catholic hierarchy and the one for which Gerten advocates, is a good option for some women — but it cannot be the exclusive one. Data from the National Survey of Family Growth show that natural family planning is used by only 1 percent of sexually active American women — including 2 percent of Catholic women.