| Level I | Good quality evidence |
Systematic review of RCTs with consistent findings High quality individual RCT |
| Level II |
Limited quality patient orientated evidence |
Systematic review of lower quality studies or studies with inconsistent findings Low quality clinical trial Cohort studies Case-control studies |
| Level III | Other |
Consensus guidelines, extrapolations from bench research, usual practice, opinion, disease-oriented evidence (intermediate or physiologic outcomes only), or case series |
[1] Levonorgestrel IUD (advantages – immediate postpartum insertion): Lopez LM, Bernholc A, Hubacher D, Stuart G, Van Vliet HA. Immediate postpartum insertion of intrauterine device for contraception. Cochrane Database Syst Rev. 2015 Jun 26;(6):CD003036. https://pubmed.ncbi.nlm.nih.gov/26115018/
Levonorgestrel IUD (advantages – immediate postpartum insertion): Abdelhakim AM, Sunoqrot M, Amin AH, et al. The effect of early vs. delayed postpartum insertion of the LNG-IUS on breastfeeding continuation: a systematic review and meta-analysis of randomised controlled trials. Eur J Contracept Reprod Health Care. 2019 Oct;24(5):327-336. https://pubmed.ncbi.nlm.nih.gov/31517549/
Levonorgestrel IUD (advantages – immediate postpartum insertion): World Health Organization. Medical eligibility criteria for contraceptive use, Fifth edition (2015). https://www.who.int/publications/i/item/9789241549158