"The biggest reason why the United States has higher infant mortality http_falls_further_behind_europe.html than other developed countries is that American women are more likely to deliver prematurely  before  weeks. And for unknown reasons the U.S. rate of preterm delivery has been going up http_.asp in recent years. Thats why its a pretty big deal that the Food and Drug Administration has OKd http a drug called HP that experts say could make a dent in the preemie problem. Not a huge dent but a significant one. The March of Dimes http calculates that if all the women eligible to get the newly approved drug actually did there would be  fewer preemies a year  out of more than halfamillion born that way http Although that may seem like a small percent its really a very extraordinary ability to impact on what is really a major public health problem Dr. Alan Fleischman http_.asp the March of Dimes medical director told Shots. According to the best research http the drug reduces the risk of premature birth by onethird among women who are at high risk because they had a previous preterm birth. Article continues after this message from our sponsor The drug is not for women whose prior premature births were of twins or other multiple births or who are carrying more than one fetus in their current pregnancy. Nor is it for women who have other conditions that raise their risk of preterm birth such as high blood pressure or infection. And even for the  or so women who are eligible HP which will be marketed as Makena isnt a magic bullet. The study showed that  percent of women who got weekly injections of it delivered prematurely compared to  percent of women who got injections of a placebo. Interestingly the drug is not new  its just taken a long and circuitous route to approval. In  the FDA approved HP for the treatment of certain cancers and other hormonal disorders under the brand name Delalutin http But its manufacturer withdrew it from the market in  for reasons unrelated to safety as the FDA puts it. In fact as a Federal Register posting last year chronicled http there have been questions raised about whether HP caused birth defects of various kinds. In the s the FDA required warnings on drugs containing progesterone as HP does because of an increased risk of birth defects. They later revoked them. The FDA is apparently satisfied that HP is safe but its requiring its sponsors KV Pharmaceuticals and TherRx to conduct further studies of women who have taken it and children exposed during pregnancy. Everyone in this field is mindful of the longrunning tragedy of vaginal and other cancers and male urinary disorders that resulted from the last drug thought to prevent premature birth  a synthetic estrogen called diethylstilbesterol or DES. In  researchers realized children exposed to DES in utero had a higher incidence of vaginal and breast cancers and males were subsequently found to have urinarytract problems. Fleischman the March of Dimes official says theres no such risk from HP partly because its not used before the th week of pregnancy when fetal organs have already formed. We have been very aggressively tracking all the data Fleischman says and we have no reason to believe that this drug will increase birth defects."