A longitudinal study of the anogenital development in girls from 6 to 12 years of age

BACKGROUND For physicians who examine allegedly abused children, it is essential to understand the range of normal variations regarding the genital and anal anatomy and microbiology. Most knowledge on this topic is from cross sectional studies. Studies with a longitudinal design is useful to describe changes resulting from growth. The aim of this study is to explore changes in anogenital anatomy and microbiology in girls resulting from growth and development. METHODS After approval from the Regional Research Ethics Committee, an invitation was send to 180 girls aged 11 to 13 years, to attend a follow up examination. All girls had previously participated in a study exploring anogenital anatomy and microbiology in children selected for non-abuse at age 5 and 6. At follow up they were examined in the same manner as at the first examination. The anogenital area was examined with a colposcope and microbiological samples for Gardnerella vaginalis and human papillomavirus were collected. GV were identified by conventional criteria and HPV by a PCR method. RESULTS Thirty one girls were examined twice at mean age 5,7 and 12,0 years. At first examination all were prepubertal. At second examination 21 girls were B2/P2 or above. Significant changes from first to second examination is summarised in table 1. More girls had developed a structure called fossa grove. Also a thick and redundant hymen with a tendency of folding outward was more common. At second examination two girls grew GV. One girl had HPV 16 identified, which was cleared at re-examination one year later. Another girl was classified to have probably a deep notch and a transaction in her hymen, and this girl reported a painful insertion of a tampon. Both girls denied sexual activity. CONCLUSION The main genital finding in girls entering puberty is the hymen becoming thick and redundant with a tendency of folding out. In the study findings associated with sexual activity were discovered, and the possibility of alternative explanations is discussed. Additional studies are needed to follow girls through puberty and to document genital changes as they initiate tampon use and consensual sexual activity.