RESUMO
To observe the effects of progestin-only hormonal contraceptives in our population. Design: Cohort study. Place and Duration of Study: Department of Pharmacology, Ziauddin Medical University, Karachi and Department of Pathology, Faculty of Health Sciences, The Aga Khan University, Karachi from October 2002 to September 2003. Patients and The study comprised of 50 women of reproductive age group, divided into two equal and matched groups of 25 each, namely, a group of users of progestin-only injectable hormonal contraceptive Norethisterone oenanthate [NET EN] 200 mg used as a 2-monthly injection and a control group not using any hormonal contraception. Complete blood counts, prothrombin time [PT] and international normalized ratio [INR] as well as activated partial thromboplastin time [APTT] were monitored. APTT and prothrombin time were not significantly different in both the groups. Menstrual irregularities were found out by more frequent in users of injectable hormonal contraceptives than in non-users [p= 0.001]. Hemoglobin [p= 0.029] and hematocrit were slightly better preserved in the same group. Use of Norethisterone oenanthate does not predispose to thrombogenesis in current dose for contraception