Implant contraception in Singaporean women: one decade of experience in KK Women's and Children's Hospital

W Kang, KH Tan
Correspondence: Dr Kang Wee, kangwee@kkh.com.sg

ABSTRACT
Introduction The aim of this study was to assess user acceptability and effectiveness of implant contraception in Singaporean women.
Methods A prospective study was carried out on 553 patients who received Norplant implant in our hospital from 1 January 1992 to 31 December 2000, and followed-up till 15 July 2003. The patients' profile, side-effects, satisfaction and continuation rate of Norplant implant were studied.
Results The mean age of the subjects was 29.4 (plus or minus 5.1) years. The mean parity was 2.1 (plus or minus 1) live births. More than one-half (55.2 percent) of the subjects had used other methods of contraception before. The main reason for them to switch to implant contraception was convenience (63.6 percent). Of the 516 users on follow-up, the common side-effects were menstrual irregularity (51 percent), secondary amenorrhoea (9.6 percent) and weight gain (15.7 percent). 29.3 percent of users did not experience any side-effect. There was only one contraceptive failure, which may be related to drug interaction. The Pearl Index was 0.054 per hundred women years. There was only one serious adverse event of a patient (0.2 percent) who developed severe hypertension requiring treatment. The continuation rate was 92.4 percent after one year, 80.8 percent after two years, 68.9 percent after three years and 58.5 percent after four years. The main reasons for early implant removal were side-effects and desire for future pregnancy. Re-insertion was carried out in 53.7 percent of users who had completed five years of Norplant contraception.
Conclusion This largest sub-dermal hormonal implant contraception study in multi-racial Singapore showed that Norplant contraception had a high degree of effectiveness with relatively high user satisfaction and continuation rate.

Keywords: contraceptive, hormonal implant, implant contraception, Norplant
Singapore Med J 2004; 45(10): 482-486