Hormonal contraceptive use among Norwegian women before first childbirth

Abstract

Introduction: Despite no major change in sexual debut, the total fertility rate in Norway has been declining over recent years. With perfect use, most modern contraceptive methods are effective to prevent conceptions. Hormonal contraceptive use is high among Norwegian women, suggesting high awareness of contraceptive behaviour and planned parenthood. This study aims to examine the contraceptive use among nulliparous women before first birth within the age of 30 years. Material and methods: Data sources for this cohort study were the Norwegian Prescription database (NorPD), the Medical Birth Registry of Norway (MBRN), and Statistics Norway. The cohort comprised 58 549 women born in Norway in 1989 and 1990. We examined their use of hormonal contraception through dispensed prescriptions from age 14/15 in 2004 to age 29/30 in 2019, as well as first birth during 2004 to 2018. The statistical analysis was done in SPSS with Chi Square and T-test at significance level p<0.05. Results: Of the total population 8.4% were not registered with neither contraceptive use nor delivery, while 2.5% were registered firstly in the birth register with no collected hormonal prescriptions prior to delivery. The remaining 89% collected a prescription of a hormonal contraceptive method before delivery within the age of 30. The combined oral contraceptive (COC) was most commonly chosen as 1st (88.3%) method, followed by the progestogen-only pill (POP) (7.4%). The other hormonal methods were less frequently used as first choice and represented combined 4.3% of 1st contraceptive use. The COC, POP, patch, and Depo-Provera were methods more commonly chosen as 1st method before the age of 20, whereas the vaginal ring (VR), implant, and levonorgestrel-releasing intrauterine device (LNG-IUD) mainly were the 1st option among women initiating use after 20 years of age. The mean duration of use ranged from 28.2 for the patch to 73.3 months for COCs. Conclusion: The study results suggest a high coverage of hormonal contraception among Norwegian women before first delivery within the age of 30. Oral contraceptives are most commonly used, and most women have collected their first prescription before the age of 19.