Spirale: donne convinte che la le protegga dall’AIDS
di Annalisa Lista – 15.03.2016
Le ragazze che usano spirale e altri contraccettivi intrauterini tendono a rifiutare il preservativo.
Convinte che i loro impianti a spirale le proteggano anche dalle malattie sessualmente trasmissibili.
È l’allarme lanciato da uno studio americano pubblicato su Jama Pediatrics. Secondo i ricercatori, che hanno esaminato il comportamento sessuale di un gruppo di liceali americane, quelle che usano la spirale sono il 60% meno favorevoli a usare contemporaneamente il condom rispetto alle coetanee che fanno uso della pillola. Ma non solo. Le prime, proprio in virtù della loro errata convinzione di fondo, sono anche quelle che hanno un numero maggiore di partner occasionali.
Lo studio sulle donne che usano la spirale:
Importance Long-acting reversible contraception (LARC), specifically intrauterine devices and implants, offers an unprecedented opportunity to reduce unintended pregnancies among adolescents because it is highly effective even with typical use. However, adolescent LARC users may be less likely to use condoms for preventing sexually transmitted infections compared with users of moderately effective contraceptive methods (ie, oral, Depo-Provera injection, patch, and ring contraceptives).
Objective To compare condom use between sexually active female LARC users and users of moderately effective contraceptive methods.
Design, Setting, and Participants Cross-sectional analysis using data from the 2013 national Youth Risk Behavior Survey, a nationally representative sample of US high school students in grades 9 through 12. Descriptive analyses were conducted among sexually active female students (n = 2288); logistic regression analyses were restricted to sexually active female users of LARC and moderately effective contraception (n = 619). The analyses were conducted in July and August 2015.
Main Outcomes and Measures Contraceptive method at last sexual intercourse was assessed by 1 item—respondents could select birth control pills; condoms; an intrauterine device or implant; injection, patch, or ring; withdrawal or other method; or not sure. A separate item asked whether respondents used a condom at last sexual intercourse. We created an indicator variable to distinguish those reporting use of (1) LARC (intrauterine device or implant), (2) oral contraceptives, and (3) Depo-Provera, patch, or ring.
Results Among the 2288 sexually active female participants (56.7% white; 33.6% in 12th grade), 1.8% used LARC; 5.7% used Depo-Provera, patch, or ring; 22.4% used oral contraceptives; 40.8% used condoms; 11.8% used withdrawal or other method; 15.7% used no contraceptive method; and 1.9% were not sure. In adjusted analyses, LARC users were about 60% less likely to use condoms compared with oral contraceptive users (adjusted prevalence ratio [aPR], 0.42; 95% CI, 0.21-0.84). No significant differences in condom use were observed between LARC users and Depo-Provera injection, patch, or ring users (aPR, 0.57; 95% CI, 0.26-1.25). The LARC users were more than twice as likely to have 2 or more recent sexual partners compared with oral contraceptive users (aPR, 2.61; 95% CI, 1.75-3.90) and Depo-Provera, patch, or ring users (aPR, 2.58; 95% CI, 1.17-5.67).
Conclusions and Relevance Observed differences in condom use may reflect motivations to use condoms for backup pregnancy prevention. Users of highly effective LARC methods may no longer perceive a need for condoms even if they have multiple sexual partners, which places them at risk for sexually transmitted infections. As uptake of LARC increases among adolescents, a clear need exists to incorporate messages about condom use specifically for sexually transmitted infection prevention.