Table II-9-2. Noncontraceptive Benefits of Steroid Contraception
Mostly Progestin Component
dysmenorrhea
• dysfunctional uterine bleeding
pelvic inflammatory disease
ectopic pregnancy
Combination Modalities
Combination OCPs. These contain both an estrogen and a progestin. They are administeredmost commonly in one of two ways: daily with 21 days on and 7 days off or daily 24 days on and 4 days off. When “off” the hormones, withdrawal bleeding will occur. Of all steroid contra-ceptives, they are the only one to have regular, predictable menses. Failure rate is 2% with ideal use. A newer combination is with daily hormones for 12 weeks followed by 1 week of placebo.
Oral Contraceptives. A unique combination of OCP (YAZ) reduces severe PMDD symptomsby 50%. It contains ethynyl estradiol and a new progestin, drospirenone. The dosing is 24 days of active pills then 4 days of placebo, rather than the traditional 21 days, followed by 7 days of placebo.
Combination Vaginal Ring. Marketed under the trade name of NuvaRing, this device,inserted into the vagina, contains both an estrogen and a progestin. It is removed after 3 weeks for 1 week to allow for a withdrawal bleed. A major advantage is relatively stable and constant blood levels of hormones. Failure rate is similar to combination OCPs.
Transdermal Skin Patch. Marketed under the trade name of Ortho Evra, this patch contains bothan estrogen and a progestin. A patch is replaced every week for 3 weeks then removed for 1 week to allow for a withdrawal bleed. Levels of steroids are 60% higher than combination OCPs.
Progestin-Only Modalities
Progestin-Only OCPs. They contain only progestins and are sometimes called the “minipill.”
They need to be taken daily and continuously. A frequent side effect is break-through bleeding.
Failure rate is 3% with ideal use.
Progestin-Only Injectable. Marketed under the trade name of Depo-Provera, this is an IMinjection of depo-medroxyprogesterone acetate (DMPA). The slow release allows administra-tion only every 3 months. A frequent side effect is break-through bleeding. Other side effects are prolonged time for fertility return and decreased bone mineral density. Failure rate is <1%.
Progestin-Only Subcutaneous Implant. Marketed under the trade name of Nexplanon, thisuses etonogestrel as the active ingredient. The core contains a small amount of barium, making it visible on x-ray. The continuous release continues for 3 years. A frequent side effect is break-through bleeding. Failure rate is <1%.
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“Morning-After” Pill. Marketed under the trade name of “Plan B,” it uses levonorgestrel tab-lets. This postcoital contraception is administered as one tablet, immediately followed by one additional tablet in 12 h. Failure rate is 1%.
General. A recent evaluation of women’s views regarding contraceptive health benefits dem-onstrated that most women are unaware of the protective effects of OCPs against endometrial and ovarian cancer, PID, ectopic pregnancy, benign breast disease, anemia, and dysmenorrhea.
Risks and Benefits. In nonsmoking women age >40, currently available OCPs are extremelysafe. Low-dose contraceptive pills do not significantly increase the risk of cancer, heart disease, or thromboembolic events in women with no associated risk factors (hypertension, diabetes, or smoking). The combination estrogen/progestin pill tends to reduce menstrual flow and dys-menorrhea, and it regulates the menses, all of which would be excellent benefits for the patient.
INTRAUTERINE CONTRACEPTION
A 30-year-old woman with Crohn disease who periodically requires steroid therapy seeks advice regarding long-term contraception. She has had 3 pregnancies. A subserosal, fundal fibroid was noted at the time of her previous cesarean section delivery. She states that she is in a mutually monogamous relationship. She was treated for a chlamydia infection 2 months ago but does not like the idea of hormonal contraception and is asking about the risks associated with an IUS.
Intrauterine contraception is a long-acting reversible contraceptive method that involves place-ment of a small t-shaped object inside the uterus. Failure rate is <1%. Continuation rates at 1 year are almost 80%.
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Mechanisms of Action. These include inhibition of sperm transport; increased tubal motilitycausing failure of implantation of immature zygote; inhibition of implantation secondary to endometrial inflammation; phagocytic destruction of sperm and blastocyst; and alteration of cervical mucus (only progesterone IUSs).
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