In general, the transdermal patch and vaginal ring produce metabolic changes, side efects, and eicacy rates comparable to those with COC pills. However, the patch has been associated with a higher thromboembolism risk in some but not all studies (Cole, 2007; Jick, 2010; Lidegaard, 2011). In response, the Food and Drug Administration (2015 b) approved labeling for the patch to state that the risk for VTE may be increased compared with other COCs, and relative risk estimates range from 1.2 to 2.2. Obesity-90 kg or greater-may be associated with a higher risk for patch contraceptive failure (Janssen Pharmaceuticals, 2015; Zieman, 2002). Finally, applicationsite reaction and breast tenderness are more frequent during initial cycles in patch wearers (Urdl, 2005).
The NuvaRing is yet another form of combination hormonal contraception and is a lexible intravaginal ring. he ring is constructed of ethinyl vinyl acetate, and it measures 54 mm in diameter and 4 mm in cross section (Fig. 38-5). During
FIGURE 38-5 NuvaRing: estrogen-progestin-releasing vaginal contraceptive ring.
insertion, the ring is compressed and threaded into the vagina, but no specific final orientation within the vagina is required.
Its core releases ethinyl estradiol and the progestin etonogestrel, which are absorbed across the vaginal epithelium. Before being dispensed, the rings are refrigerated, and once dispensed, their shelflife is 4 months. he ring is placed within 5 days of menses onset and, after 3 weeks of use, is removed for 1 week to allow withdrawal bleeding. Contraception will still be aforded if a ring is left in place for a fourth week (Merck, 2016b).
Patient satisfaction is high with this method, although vagi nitis, ring-related events, and leukorrhea are more common (Lopez, 2013b; Oddsson, 2005). Despite this, no deleterious been found (Lete, 2013; Veres, 2004). A ring may be used con currently with vaginal medications or with a tampon (Haring, 2003; Verhoeven, 2004a,b). Approximately 70 percent of part ners feel the ring during intercourse (Dieben, 2002). If this is bothersome, the ring may be removed for intercourse but should be replaced within 3 hours to maintain eicacy.
Both intramuscular depot medroxyprogesterone acetate-DepoProvera (DMPA)-150 mg every 3 months, and norethisterone enanthate, 200 mg every 2 months, are injectable progestin contraceptives used worldwide. Of the two, DMPA is available in the United States. DMPA is injected into the deltoid or gluteus muscle, but massage is avoided to ensure that the drug is released slowly. lternatively, a subcutaneous version, depo-subQprovera 104, is also available and is injected into the subcutaneous tissue of the anterior thigh or abdomen every 3 months.