title: Bleeding patterns of adolescents using a combination contraceptive injection for 1 year.
abstract: OBJECTIVE
  This prospective observational study evaluated the bleeding patterns of adolescents receiving a monthly injectable contraceptive containing norethisterone enanthate 50 mg plus estradiol valerate 5 mg.
  
  
  METHODS
  The study enrolled 73 volunteers aged between 14 and 19 years; of these patients, 38 (52%) recorded their menstrual cycles during 1 year.
  
  
  RESULTS
  After 1 year of using the contraceptive, most of the 38 women (71.1%) had adequate menstrual patterns (two to four bleeding episodes; none lasting 10 days or longer; with a range of bleeding-free intervals not exceeding 17 days), 23.7% reported prolonged bleeding episodes, 2.6% had irregular bleeding and 2.6% had amenorrhea. Only 1 of the 38 teenagers is known to have discontinued the method due to bleeding. Among these 38 adolescents, dissatisfaction with bleeding patterns was not a frequent reason given for discontinuation of the monthly injectable contraceptive.
authors.affiliation: Family Planning Clinic, Department of Obstetrics and Gynecology, São Paulo Federal University, São Paulo, Brazil.
authors.forename: Maria Silvia
authors.initials: MS
authors.lastname: Bortolotti de Mello Jacobucci
authors.forename: Cristina Aparecida Falbo
authors.initials: CA
authors.lastname: Guazzelli
authors.forename: Márcia
authors.initials: M
authors.lastname: Barbieri
authors.forename: Fabio Fernando
authors.initials: FF
authors.lastname: Araújo
authors.forename: Antonio Fernandes
authors.initials: AF
authors.lastname: Moron
mesh_terms: D000293:Adolescent; D000328:Adult; D003271:Contraceptive Agents, Female / Q000008:administration & dosage* / Q000009:adverse effects; D004338:Drug Combinations; D004958:Estradiol / Q000008:administration & dosage / Q000031:analogs & derivatives*; D005260:Female; D006801:Humans; D007273:Injections, Intramuscular; D008598:Menstruation / Q000187:drug effects*; D008599:Menstruation Disturbances / Q000139:chemically induced; D009640:Norethindrone / Q000008:administration & dosage / Q000031:analogs & derivatives*; D010349:Patient Compliance; D011446:Prospective Studies
chemical_list: D003271:Contraceptive Agents, Female; D004338:Drug Combinations; D004958:Estradiol; C024319:norethindrone enanthate; D009640:Norethindrone