title: The Effect of Age, Parity and Body Mass Index on the Efficacy, Safety, Placement and User Satisfaction Associated With Two Low-Dose Levonorgestrel Intrauterine Contraceptive Systems: Subgroup Analyses of Data From a Phase III Trial.
abstract: OBJECTIVE
  Two low-dose levonorgestrel intrauterine contraceptive systems (LNG-IUSs; total content 13.5 mg [average approx. 8 μg/24 hours over the first year; LNG-IUS 8] and total content 19.5 mg [average approx. 13 μg/24 hours over the first year; LNG-IUS 13]) have previously been shown to be highly effective (3-year Pearl Indices: 0.33 and 0.31, respectively), safe and well tolerated. The present subgroup analyses evaluated whether or not outcomes were affected by parity, age (18-25 vs 26-35 years), or body mass index (BMI, <30 vs ≥30 kg/m2).
  
  
  METHODS
  Nulliparous and parous women aged 18‒35 years with regular menstrual cycles (21‒35 days) requesting contraception were randomized to 3 years of LNG-IUS 8 or LNG-IUS 13 use.
  
  
  RESULTS
  In the LNG-IUS 8 and LNG-IUS 13 groups, 1432 and 1452 women, respectively, had a placement attempted and were included in the full analysis set; 39.2%, 39.2% and 17.1% were 18-25 years old, nulliparous and had a BMI ≥30 kg/m2, respectively. Both systems were similarly effective regardless of age, parity or BMI; the subgroup Pearl Indices had widely overlapping 95% confidence intervals. Placement of LNG-IUS 8 and LNG-IUS 13 was easier (p < 0.0001) and less painful (p < 0.0001) in women who had delivered vaginally than in women who had not. The complete/partial expulsion rate was 2.2-4.2% across all age and parity subgroups and higher in parous than in nulliparous women (p = 0.004). The incidence of pelvic inflammatory disease was 0.1-0.6% across all age and parity subgroups: nulliparous and younger women were not at higher risk than parous and older women, respectively. The ectopic pregnancy rate was 0.3-0.4% across all age and parity subgroups. Across all age and parity subgroups, the 3-year completion rate was 50.9-61.3% for LNG-IUS 8 and 57.9-61.1% for LNG-IUS 13, and was higher (p = 0.0001) among older than younger women in the LNG-IUS 8 group only.
  
  
  CONCLUSIONS
  LNG-IUS 8 and LNG-IUS 13 were highly effective, safe and well tolerated regardless of age or parity.
  
  
  BACKGROUND
  Clinical trials.gov NCT00528112.
authors.affiliation: Department of Women's and Children's Health, Division of Obstetrics and Gynecology, Karolinska Institutet and Karolinska University Hospital, Stockholm, SE-171 76, Sweden.
authors.forename: Kristina
authors.initials: K
authors.lastname: Gemzell-Danielsson
authors.affiliation: Sexual Health Clinic (Family Federation of Finland), Väestöliitto, Helsinki, 00101, Finland.
authors.forename: Dan
authors.initials: D
authors.lastname: Apter
authors.affiliation: Department of Obstetrics and Gynecology, Foothills Hospital, University of Calgary, Calgary, Alberta, T2N 4J8, Canada.
authors.forename: Brian
authors.initials: B
authors.lastname: Hauck
authors.affiliation: Bayer Pharma AG, Müllerstrasse 178, Berlin, 13353, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Schmelter
authors.affiliation: Bayer HealthCare Pharmaceuticals, Whippany, New Jersey, United States of America.
authors.forename: Sarah
authors.initials: S
authors.lastname: Rybowski
authors.affiliation: Bayer HealthCare Pharmaceuticals, Whippany, New Jersey, United States of America.
authors.forename: Kimberly
authors.initials: K
authors.lastname: Rosen
authors.affiliation: Los Angeles Biomedical Research Institute, Harbor-UCLA, 1000 West Carson Street Torrance, California, 90405, United States of America.
authors.forename: Anita
authors.initials: A
authors.lastname: Nelson
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D015992:Body Mass Index; D003258:Consumer Behavior / Q000706:statistics & numerical data*; D003271:Contraceptive Agents, Female / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007436:Intrauterine Devices, Medicated / Q000009:adverse effects* / Q000706:statistics & numerical data; D016912:Levonorgestrel / Q000008:administration & dosage / Q000009:adverse effects* / Q000494:pharmacology*; D010146:Pain / Q000209:etiology; D010298:Parity; D011247:Pregnancy; D012449:Safety; D055815:Young Adult
chemical_list: D003271:Contraceptive Agents, Female; D016912:Levonorgestrel