Pubmed里面的一篇paper 《关于棉条使用和处女膜孔大小的临床研究结果》
paper link在此：http://www.ncbi.nlm.nih.gov/pubmed?term=8021768
Hymenal findings in adolescent women: impact of tampon use and consensual sexual activity.
Abstract
We undertook a prospective study of 300 postmenarcheal female subjects (median age, 18.0 years) to examine (1) the relation of tampon use, sports participation, prior gynecologic examination, and consensual sexual activity to hymenal anatomy, (2) the factors leading to choice of tampons by girls not sexually active, and (3) factors related to ease of gynecologic examination. The sample included 100 subjects in group 1, who denied sexual intercourse and used only pads for menses; 100 subjects in group 2, who denied sexual intercourse and had used tampons; and 100 subjects in group 3, who gave a history of sexual intercourse. Sexually active subjects (81%) were significantly more likely than tampon users and pad users to have "complete clefts" in the lower hymen between the 2 o'clock and 10 o'clock positions (p < 0.001); tampon users were not significantly different from pad users (11% vs 5%). In subjects who were not sexually active, the presence of these complete clefts was not related to participation in sports or to prior pelvic examination. Although median hymenal opening diameter differed in the three groups (1.2 cm for group 1 vs 1.5 cm for group 2 vs 2.5 cm for group 3; p < 0.0001), the ranges of measurements were wide. Tampon users were significantly more likely than pad users to have mothers and friends, but not sisters, who had a favorable attitude toward tampon use. The best predictors of tampon use in a multivariate model were a favorable maternal attitude (odds ratio (OR), 5.3; 95% confidence interval (CI), 2.4, 12.1) and friends' use of tampons (OR 7.9; 95% CI 3.5, 18.1). Only 26% of speculum examinations in pad users were rated as easy compared with 56% of examinations in tampon users and 81% in sexually active young women (p < 0.001). The best predictors of ease of speculum examination were sexual activity (OR 15.9; 95% CI 1.9, 135.3) and tampon use (OR 3.6; 95% CI 1.0, 12.7). This large sample should provide useful data for physicians who testify in sexual assault cases and gives new information on the predictors of tampon use and ease of gynecologic examination in young women.
我就不逐字逐句翻译了，总结一下：
300个对象
1）100 用卫生巾，处女
2）100 用棉条，处女
3）100 性交过的
结果：
3组81%，2组11%，1组5%的对象10点和2点之间的处女膜完全破裂
这些1组和2组对象完全破裂不是妇科检查或体育运动造成的
平均处女膜孔尺寸 （p<0.0001。说明三组之间的区别绝基本绝对没有机率是偶然的）：
1组： 1.2cm
2组： 1.5cm
3组： 2.5cm
（paper学术贴求赏桃赏花赏分~~~）
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