I was in an arguement with a colleague over the internet recently. It had to do with abortion, but he brought up that abstinence training decreases unintended pregnancies by 42%. Knowing he is slightly to the right of the right turn only sign I figured that this was idealogic in origins. So I asked our librarian to do some research. She found 19 documents in Pubmed. Searching through those I only found two that were somewhat releavant. Most had to do with teaching and problems with teaching abstinence. The best one that was on point was published in Pediatrics in Jan of 2009 by JE Rosenbaum of the Health Policy PhD program at Harvard university. It had the title of "Patient teenagers: A comparison of the sexual behavior of virginity pledgers and matched nonpledgers". It compared pledgers with number of 289 participants with nonpledgers with a number of 645 participants. It compared the results after 5years self reported sex behavior and positive test results for STD's (sexually transmitted diseases, of chlamydia, gonorrhea, trichmonas) and safe sex outside marriage by use of birth control and condoms in the past year and last sex. The results are illuminating. 82% of pledgers denied ever having pledged. Pledgers and nonpledgers did not differ in premarital sex, STD's and anal/oral sex variables. Pledgers has 0.1% fewer past year partners but did not differ in lifetime sex partners and age at first sex. Fewer pledgers than the matched nonpledgers used birth control and condoms. The conclusion of the study stated that the sex behavior of virginity pledgers does not differ from that of closely matched nonpledgers. Pledgers were less likely to protect themselves from pregnancy and STDs. And pledging may decrease the likelihood of the taking precautions during sex. I have no idea where the 42% came from as decreasing the unintended pregancy. I have the librarian trying to find more studies. The Harvard study was the only one that compared outcomes of pledging with nonpledging and was well run study. So at this point I can only suspect that my "colleague" was feeding me data that he was fed by ideologic right wing. If any data comes up that proves me wrong I will admit it, will the right wing fundamentalist do the same.