Вагинальное кольцо НуваРинг: применение, эффективность и распространенные вопросы.

The ethinylestradiol/etonogestrel vaginal ring is also known as NuvaRing. It is a flexible plastic (ethylene vinyl acetate copolymer) ring that releases a low dose of a progestin and estrogen over three weeks. The slow release of the hormones prevents pregnancy by blocking ovulation and causes changes in the cervical mucus that may stop implantation from occurring, as well.

The low dose is a constant rate that averages to about 0.015 mg of ethinyl estradiol and 0.12 mg etonogestrel per day.

The contraceptive vaginal ring can be used at any time during the menstrual cycle as long as the patient is not currently pregnant. The standard process for administration is to insert the ring and leave it inside the vagina for 21 days, then remove it and have a break for 7 days without the ring inserted. After the 7 day break, a new ring should be reinserted for a 21 day period, and the cycle will continue thereafter. However, some patients may choose to have a shorter ring free break or no break at all, which has been shown to be just as safe and effective as the regimen with breaks. About 9% of individuals using a vaginal ring will still get pregnant every year, although this drops to 1% with perfect use. The most common mistakes when using the ring are adherence issues and incorrect administration, including forgetting to replace the ring on time and failure to insert the ring far enough into the vagina. A study in Kenya demonstrated that there was concern circling on vaginal insertion and ring placement that called for practice from users, initially. Comparably, in Rwanda participants, there were challenges with ring insertion and removal originally but those worries dissipated with practice, and later described the process as "easy". Multiple other common reasons for nonadherence include removing the ring for washing or before sexual intercourse. If the ring has been removed for more than three hours, then backup contraception should be used until the ring has been inserted and back in place for at least seven days. Due to lack of patient education, some users struggle to insert the device comfortably and completely, which may hinder the contraceptive effects of the ring. A large number of accidental expulsion of the vaginal ring occurs in the first few weeks of ring use, further suggesting inadequate or absence of counseling in use of contraceptive vaginal rings or inexperience in vaginal ring use.

For any individual interested in using a contraceptive vaginal ring, it is important for their healthcare provider to provide counseling and support their understanding on these topics to ensure proper usage techniques and time. There is a small chance of blood clots, heart attacks and stroke with vaginal rings, and they are not recommended for individuals over 35 who smoke. Studies find that 2.4% to 6.4% of contraceptive vaginal ring users experience uterine bleeding. A common concern with contraceptive vaginal rings are that they will impact vaginal health. Multiple studies have demonstrated that vaginal health is not impacted as contraceptive vaginal rings do not affect the vaginal microbiome. It is a silicone elastomer vaginal ring containing the progestin segesterone acetate and the estrogen ethinylestradiol. Side effects are not common but may be present in some patients as a result of the hormones released by the ring. These side effects could include headaches, nausea, changes in period/menstrual cycle, sore breasts, or increased vaginal discharge. These symptoms are most common when the patient first begins using the ring and often subside within the first 2–3 months. While these are not necessarily reasons for concern, patients should always contact their primary care provider if they feel sick or faint, as it may be a sign for more serious adverse events in which case the vaginal ring usage should be discontinued.

A progesterone vaginal ring (PVR) has also been developed. The progesterone rings are highly effective for breastfeeding parents because exclusive breastfeeding itself, inducing lactational amenorrhea, provides some protection from pregnancy,

Approximately 10 mg of progesterone diffuses from the ring per day through the vaginal walls into the bloodstream to suppress ovulation as well as thickening the cervical mucus to prevent sperm penetration into the uterus.

Side effects include, but are not limited to, vaginal discharge, breast pain, and spotting or irregular bleeding. Also, unlike the pill, it is not affected by gastrointestinal issues, such as vomiting and diarrhea, as the hormones are directly absorbed into the bloodstream. The estrogen dosing is lower compared to that of contraceptive pills and patches, which results in fewer side effects related to estrogen. Additionally, there are a lower incidence rates of drug drug interactions because the route does not involve the gastrointestinal tract, but rather the vaginal epithelium. In a 2014 study conducted in Chilean individuals, a positive correlation between contraceptive counseling and preference for contraceptive vaginal rings has been demonstrated. Preferences for an oral pill formulation, which was the most popular option, decreased after physician counseling; whereas, preferences for vaginal rings and transdermal patches increased after physician counseling. An additional benefit is that the bleeding pattern of the contraceptive vaginal ring is consistent over a year long period, which has led to lower discontinuation rates.

Though it requires less maintenance, the vaginal ring will still have to be placed and removed at the right time. Unscheduled ring removals can increase the risk of failure, and further studies are needed to evaluate the efficacy of the ring beyond a 21 day period.