title: Bone density in adolescents treated with a GnRH agonist and add-back therapy for endometriosis.
abstract: OBJECTIVE
  To evaluate the bone density of adolescents with endometriosis treated with a GnRH-agonist and "add-back" therapy with norethindrone acetate.
  
  
  METHODS
  Retrospective chart review.
  
  
  METHODS
  Pediatric gynecology clinic at a tertiary care center.
  
  
  METHODS
  36 adolescents, ages 13 to 21 years, with endometriosis.
  
  
  METHODS
  Bone mineral density (BMD, g/cm(2)) by dual energy x-ray absorptiometry (DXA); BMD Z-scores of hip and spine.
  
  
  RESULTS
  The mean BMD Z-score at the total hip was -0.24 +/- 1.0, with a range of -2.4 to 1.7. At this site, 6 subjects had a BMD Z-score between -1.0 and -2.0 SD, while 2 had a Z-score < or = -2.0 SD. The mean BMD Z-score at the lumbar spine was 0.55 +/- 1.1, with a range of -2.8 to 1.4. At the spine, 11 subjects had a BMD Z-score between -1.0 and -2.0 SD, while 3 had a Z-score < or = -2.0 SD. There was no correlation noted between duration of therapy with the GnRH-agonist plus add-back and BMD at the hip or spine.
  
  
  CONCLUSIONS
  BMD at the hip was normal in most adolescents with endometriosis who were receiving a GnRH-agonist plus add-back therapy with norethindrone acetate. Almost one third of subjects exhibited skeletal deficits at the spine. These data suggest that BMD should be carefully monitored in adolescents receiving treatment with GnRH agonists.
authors.affiliation: Division of Adolescent Medicine, Children's Hospital Boston, MA 02115, USA. amy.divasta@childrens.harvard.edu
authors.forename: Amy D
authors.initials: AD
authors.lastname: Divasta
authors.forename: Marc R
authors.initials: MR
authors.lastname: Laufer
authors.forename: Catherine M
authors.initials: CM
authors.lastname: Gordon
mesh_terms: D015502:Absorptiometry, Photon; D000293:Adolescent; D000328:Adult; D015519:Bone Density / Q000187:drug effects; D015331:Cohort Studies; D004715:Endometriosis / Q000188:drug therapy*; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000819:agonists*; D006615:Hip / Q000000981:diagnostic imaging; D006801:Humans; D016729:Leuprolide / Q000627:therapeutic use*; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging; D009640:Norethindrone / Q000031:analogs & derivatives* / Q000627:therapeutic use; D000077563:Norethindrone Acetate
chemical_list: D007987:Gonadotropin-Releasing Hormone; D000077563:Norethindrone Acetate; D016729:Leuprolide; D009640:Norethindrone