Answer
Evra primarily prevents pregnancy by inhibiting ovulation through gonadotropin suppression by ethinylestradiol and norelgestromin; changes in cervical mucus and the endometrium may also contribute.
Sources for this answer
- EVRA 203 micrograms/24 hours + 33.9 micrograms/24 hours transdermal patchGedeon Richter (UK) Ltd · emc · SmPC §5.1 Pharmacodynamic properties · Version 3Document updated
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