Changes in menstrual and haematological indices among Norplant acceptors.

A longitudinal study of women using Norplant(R) was conducted to determine the effects of levonorgestrel implants on menstrual and haematological indices among the acceptors. Packed cell volume (PCV), white blood cell (WBC) concentrations (total and differential), and platelet concentration were performed at pre-insertion and at the 12-month follow-up. Each acceptor received a menstrual calendar to chart all bleeding, and spotting events. The mean PCV was 40.5 +/- 2. 4 at insertion and had a statistically significant (p <0.01) rise to a mean value of 42.2 +/- 2.6 at 12 months. The mean WBC concentration had a significant decrease at 12 months (p <0.001) when compared with the pre-insertion value. Similarly, the neutrophil and lymphocyte concentration had a statistically significant decrease (p <0.05 and p <0.01, respectively) at 12 months of use. The reduced values in the concentrations of monocytes, eosinophils and basophils did not reach significant levels. The mean value of the platelet concentrations had a significant decline at 12 months of use (p <0.001). Reduced bleeding patterns were more commonly reported compared to increased bleeding episodes. This pattern was associated with increased PCV, a change that may prevent anaemia in developing countries. The decline in the platelet concentration at 12 months of study was, however, a source of concern that will require follow-up.