Abstract 031: Association Between Non-Oral Hormonal Contraceptives and Blood Pressure: A Systematic Review

Abstract

Background: Combined oral contraceptives (COCs) are associated with increased blood pressure (BP) and hypertension. Whether non-oral forms of hormonal contraceptive (NOHC) have similar associations is unknown. Methods: We conducted a systematic review investigating the association between NOHC use and blood pressure compared to women using COC and non-hormonal contraception (NHC). Three databases (MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials) were searched for articles published from database inception through October 2018. Primary studies examining women using NOHC [transdermal, hormonal intrauterine device (IUD), implant, vaginal ring or injectables] compared with women using COC or NHC were included. Two independent investigators screened identified abstracts. Data on study population, hormonal exposure, outcomes, study quality and risk of bias were independently extracted from each eligible study. Primary outcomes were change in BP or prevalence of hypertension. Quality of case control and cohort studies was assessed using the Newcastle-Ottawa scale. Quality of randomized control trials was assessed using the Cochrane risk of bias tool. Results: Of 3981 studies reviewed, 22 met inclusion criteria (12 studies on injectables, 6 on implants, 4 on hormonal IUDs, 3 on the vaginal ring). Some studies examining the effect of IUD use showed a significantly lower BP compared to COC use, and no difference compared to NHC users. No differences in BP were reported with vaginal ring use compared to COC or NHC use. Conflicting results were presented with implant use compared to NHC use, but no change in BP compared to COC. Five studies reported increased BP with injectable use compared to COC and NHC, while seven studies showed no change in BP. All women remained in the normotensive range in all included studies. Conclusion: Non-oral hormonal contraceptive use is associated with increases in blood pressure, though the effects differ by route of administration. These results may inform contraceptive choices in women with or at risk of hypertension.