Contraceptives, vaginal ring

Weisberg, E., et al. 1997. Effect of different insertion regimens on side effects with a combination contraceptive vaginal ring. Contraception 56 233. 

Roumen, F. J., and Dieben, T. O. (1999), Clinical acceptability of an ethylene-vinyl-acetate nonmedicated vaginal ring, Contraception, 59, 59-62. 

Timmer, C. Apter, D. Voortman, G. Pharmacokinetics of 3-keto-desogestrel and ethinylestradiol released from different types of contraceptive vaginal rings. Contraception 1990, 42 (6), 629-642. 

Vaginal Rings. Vaginal epithelium is readily permeable to contraceptive steroids. Since the vascular drainage of the vagina bypasses the Hver, this route of adrninistration potentially permits utilisation of dmgs that have low oral activity. 

Starting the contraceptive vaginal ring - Consider the possibility of ovulation and conception prior to the first use of the contraceptive vaginal ring. 

Switching from a combination oral contraceptive Insert the contraceptive vaginal ring anytime within 7 days after the last combined (estrogen plus progestin) oral contraceptive tablet and no later than the day that a new cycle of pills would have started. No backup method is needed. 

Switching from a progestin-only method Insert the first contraceptive vaginal ring as follows ... 

Any day of the month when switching from a progestin-only pill do not skip any days between the last pill and the first day of contraceptive vaginal ring use ... 

Following complete first-trimester abortion The patient may start using the contraceptive vaginal ring within the first 5 days following a complete first trimester abortion and does not need to use an additional method of contraception. If use is not started within 5 days following a first trimester abortion, the patient should follow the instructions for No preceding hormonal contraceptive use in the past month. Advise the patient to use a nonhormonal contraceptive method. 

Consider the possibility of pregnancy if the ring-free interval has been extended beyond 1 week. Use an additional method of contraception until the contraceptive vaginal ring has been used continuously for 7... 

In the event of a missed menstrual period If the patient has not adhered to the prescribed regimen, consider the possibility of pregnancy at the time of the first missed period and discontinue the use of the contraceptive vaginal ring if pregnancy is confirmed. 

Vaginal ring - Advise women who are breast-feeding not to use the contraceptive vaginal ring but to use other forms of contraception until the child is weaned. 

Vaginal use The contraceptive vaginal ring may not be suitable in conditions that make the vagina more susceptible to vaginal irritation or ulceration. 

The contraceptive vaginal ring may interfere with the correct placement and position of a diaphragm. A diaphragm is not recommended as a backup method with contraceptive vaginal ring use. 

Only one implantable contraceptive preparation is available at present in the USA. Etonogestrel, also used in some oral contraceptives, is available in the subcutaneous implant form listed in Table 40-3. Several hormonal contraceptives are available as vaginal rings or intrauterine devices. Intramuscular injection of large doses of medroxyprogesterone also provides contraception of long duration. 

As early as 1978, the vaginal administration of steroids for contraceptive purposes was attempted, at that time using vaginal rings containing medroxyprogesterone acetate or... 

Despite the head start afforded to progestogen-only vaginal rings, the first contraceptive ring to reach market was the combined contraceptive ring, NuvaRing. It is a nonbiodegradable,... 

Massai, R., et al. 1999. Pre-registration study on the safety and contraceptive efficacy of a progesterone-releasing vaginal ring on Chilean nursing women. Contraception 60 9. 

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