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.

Method: 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

Conclusion: 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.