title: Haemostatic function in Norplant (levonorgestrel) users: a 3-year prospective experience in Benin-City, Nigeria.
abstract: OBJECTIVE
  To evaluate the haemostatic function and menstrual pattern of Norplant acceptors after 36 months of use.
  
  
  METHODS
  This was a prospective longitudinal study that involved fifty five healthy, non-breastfeeding, sexually active informed volunteers recruited from our family planning clinic, between September and December 2002. Blood samples were collected at pre-insertion, 12, 24 and 36 months follow up for packed cell volume, platelet count, prothrombin time and activated partial thromboplastin time. Statistical analysis was with paired t-test. The level of significance was set at p<0.05. Each acceptor received a menstrual calendar to chart all bleeding events.
  
  
  RESULTS
  The mean age and weight of the 29 acceptors who had complete records at 36 months of study were 33.7 +/- 5.9 years, 64.1 +/- 9.9 kg respectively. The mean packed cell volume (PCV) was 34.3 +/- 2.5% at pre-insertion. This rose to significant mean +/- SD values of 37.6 +/- 3.5%; p < 0.0002, 37.4 +/- 3.2%: p < 0.0001 and 38.0 +/- 2.6%; p < 0.0001 at 12, 24 and 36 months respectively. The mean platelet count at pre-insertion was (239,724 +/- 85,886 per microl). There were significant reductions in the mean concentration at 12 months (p <0.04; 198,310 +/- 78,476 per microl) and at 36 months (p<0.0002; 154,241+/- 45,207 per microl). The prothrombin and the partial thromboplastin time at 12, 24 and 36 months did not show significant change over their pre-insertion mean values of 11.9 +/- 1.1 seconds and 36.9 +/- 3.0 seconds respectively. At 24 and 36 months 75.9% (22) and 72.4% (21) of the users reported abnormal menstrual patterns respectively. Only 24.2% (7) and 27.6% (8) had normal menstrual patterns at the respective months. Continuation rates at the end of 24 and 36 months of studies were 85.5% (47) and 80% (44) respectively. Reasons for discontinuation were planning for another baby, menorrhagia, lump in the breast and elevated blood pressure
  
  
  CONCLUSIONS
  Acceptors of Norplant had mainly reduced bleeding patterns, which did not predispose them to anaemia neither did they have an adverse effect as a result of the reduced but normal platelet count.
authors.affiliation: Department of Obstetrics and Gynaecology, University of Benin Teaching Hospital, Benin-City, Nigeria. aisienao@yahoo.com
authors.forename: A O
authors.initials: AO
authors.lastname: Aisien
authors.forename: M E
authors.initials: ME
authors.lastname: Enosolease
mesh_terms: D000328:Adult; D003271:Contraceptive Agents, Female / Q000009:adverse effects*; D005260:Female; D006400:Hematocrit; D006487:Hemostasis / Q000187:drug effects*; D006801:Humans; D016912:Levonorgestrel / Q000009:adverse effects*; D008599:Menstruation Disturbances / Q000139:chemically induced / Q000453:epidemiology; D009549:Nigeria / Q000453:epidemiology; D010314:Partial Thromboplastin Time; D011446:Prospective Studies; D011517:Prothrombin Time
chemical_list: D003271:Contraceptive Agents, Female; D016912:Levonorgestrel