566 Final Exam Study Guide
Week 5
Prevention of osteoporosis with hormone replacement therapy (p. 433)
Hormone therapy (HT) reduces postmenopausal bone loss & thereby decreases the risk for osteoporosis & related fractures. Unfortunately, when HT is stopped, bone mass rapidly decreases by approximately 12%. Hence to maintain bone health, HT must continue lifelong. As a result, the risk for harm is increased. Accordingly, alternative treatments are
preferred. Effective alternatives to HT include raloxifene (Evista) & bisphosphonates like alendronate (Fosamax), calcitonin (Miacalcin), & teriparatide (Forteo). All patients should practice primary prevention of bone loss by ensuring adequate intake of calcium & vitamin D, performing regular weight-bearing exercise, & avoiding smoking & excessive alcohol use.
When and when not to use progestin for hormone replacement therapy and why (pp. 430-433)
Goals for noncontraceptive uses of progestins are to counteract endometrial hyperplasia caused by unopposed estrogen during hormone therapy; management of dysfunctional uterine bleeding, amenorrhea, & endometriosis; & support of pregnancy in women with corpus luteum deficiency. Progestins are also used in in vitro fertilization cycles & to prevent prematurity in women at high risk for preterm birth.
Progestins are contraindicated in the presence of undiagnosed abnormal vaginal bleeding. Relative contraindications include active thrombophlebitis or a history of thromboembolic disorders (DVT, CVA), active liver disease, & carcinoma of
the breast. Progestins should not be prescribed for women who have undergone hysterectomy.
Local vs. systemic estrogen options and why one would be chosen over the other (p. 428)
Local estrogen options :
Transdermal: Transdermal estradiol is available is 4 formulations:
Emulsion (Estrasorb): Applied once daily to the top of both thighs & the back of both calves.
Spray (Evamist): Applied once daily to the forearm.
Gels (EstroGel, Elestrin, Divigel) : Applied once daily to one arm, from the shoulder to the wrist or to the thigh (Divigel).
Patches (Alora, Climara, Estraderm, Menostar, Vivelle-Dot) : Applied to the skin of the trunk (but not the breast).
Intravaginal: Estrogens for intravaginal administration are available as inserts, creams, & vaginal rings. All are used primarily for the treatment of vulval & vaginal atrophy associated with menopause. NOTE: Femring is also used for systemic effects to control hot flashes & night sweats.
Inserts (Imvexxy, Vagifem, Yuvafem)
Creams (Estrace Vaginal, Premarin Vaginal)
Vaginal rings (Estring, Femring)
Systemic estrogen options :
Oral: Owing to convenience, the oral route is used more than any other. The most active estrogenic compound—
estradiol—is available alone & in combination with progestins.
Parenteral: Although estrogens are formulated for IV & IM administration, use of these routes is rare. IV administration is generally limited to acute, emergency control of heavy uterine bleeding. Transdermal estrogen therapy has fewer adverse effects (p. 428)
Compared with oral formulations, the transdermal formulations have 4 advantages:
The total dose of estrogen is greatly reduced (because the liver is bypassed).
There is less nausea & vomiting.
Blood levels of estrogen fluctuate less.
There is a lower risk for DVT, PE, & CVA.
Management of oral contraceptives (OCs)
-How to change patient from one combination oral contraceptive to another. (p. 441)
When one combination OC is being substituted for another, the change is best made at the beginning of a new cycle.
-How to initiate treatment (when in the cycle is it best to start- may vary based on type of contraceptive) (p. 442)
Most 28-day cycle products are taken in a repeating sequence consisting of 21 days of an active pill followed by 7 days on
which either no pill is taken, an inert pill is taken, or an iron-containing pill is taken. The sequence is begun on either the first day of the menstrual cycle or the first Sunday after the onset of menses. With the first option, protection is conferred immediately, so no backup contraception is needed. With a Sunday start, which is done to have menses occur on weekdays rather than the weekend, protection may not be immediate, so an alternate form of birth control should be
used during the first 7 days of the pill pack. With both options, each dose should be taken at the same time every day (with a meal or at bedtime). Successive dosing cycles should commence every 28 days even if there is breakthrough bleeding or spotting.
Unlike combination OCs, whose administration is cyclic, progestin-only OCs are taken continuously. Use is initiated on day
1 of the menstrual cycle, & one pill is taken daily thereafter. A backup contraceptive method should be used for the first 7
days.
-What teaching needs to be done? (p. 442)
Educate patient on proper protocol for missed doses (depending on medication type & cycle):
For products that use a 28-day cycle, the following recommendations apply:
If one or more pills are missed in the first week, take one pill as soon as possible & then continue with the pack. Use an additional form of contraception for 7 days.
If one or two pills are missed during the second or third week , take one pill as soon as possible & then continue with the active pills in the pack but skip the placebo pills & go straight to a new pack once all the active pills have been taken.
If three or more pills are missed during the second or third week , follow the same instructions given for missing one or two pills but use an additional form of contraception for 7 days. For combination OCs that use an extended or continuous cycle , up to 7 days can be missed with little or no increased risk for pregnancy provided that the pills have been taken continuously for the prior 3 weeks.
For progestin-only OCs, if one or more doses is missed or taken greater than 3 hours after the scheduled dose, the following guidelines apply:
If one pill is missed, it should be taken as soon as remembered & backup contraception should be used for at least 2 days. The pills should be resumed as scheduled on the next day.
If two pills are missed, the regimen should be restarted & backup contraception should be used for at least 2 days. In addition, if two or more pills are missed & no menstrual bleeding occurs, a pregnancy test should be done.
Effectiveness of oral contraceptives can be reduced with some medications, including certain common antibiotics.
-What baseline data is needed? (p. 446)
Assess for history of hypertension, diabetes, thromboembolism, cerebrovascular or cardiovascular disease, breast cancer.
Urine pregnancy test.
-Contraindications for OCs (p. 446)
Contraindications to use include current pregnancy, history of thromboembolus, breast cancer, & women over 35 years of age who continue to smoke tobacco. Use with caution in women with diabetes, hypertension, & cardiac disease.
How to achieve an extended cycle with oral contraceptives (p. 442)
Many health care providers recommend taking combination OCs for an extended time rather than following the traditional 28-day cycle because doing so decreases episodes of withdrawal bleeding, with the associated menstrual pain, premenstrual symptoms, headaches, & other problems. Prolonged use of OCs is possible because these drugs suppress endometrial thickening, hence monthly bleeding is not required to slough off hypertrophied tissue. At this time,
14 products are packaged & marketed for prolonged use.
It is important to note that there is nothing special about the estrogen/progestin combinations used in these extended-
cycle products. In other words, we could get the same results with other combination OCs, provided they are monophasic. To achieve an extended schedule, the user would simply purchase four packets of a 28-day product (each of
which contains 21 active pills) & then take the active pills for 84 days straight.
What behaviors would make one birth control method more effective over another? (pp. 437-438)
-Be able to evaluate a patient scenario and suggest an appropriate birth control method (type of prescribed contraception: OC, long-term methods, IUD, etc.
With perfect use, the failure rate for OCs is only 0.3%. However, with typical use, the failure rate is significantly higher: about 8%. Among women of higher weight, efficacy is somewhat reduced. Possible reasons include decreased blood levels of the hormones, sequestration in adipose tissue, & altered metabolism.
Combination OCs should be avoided by women with certain cardiovascular disorders & those older than 35 years who smoke. For women in these categories, an alternative method (diaphragm, progestin-only pill, or IUD) is preferable.
Additional factors that bear on selecting a birth control method include family planning goals, age, frequency of sexual intercourse, & the individual’s capacity for adherence. If family planning goals have already been met, sterilization of either the male or female partner may be desirable. For women who engage in coitus frequently, OCs or a long-term method (Nexplanon, Depo-Provera, IUD) are reasonable choices. Conversely, when sexual activity is limited, use of a spermicide, condom, or diaphragm may be more appropriate. Because barrier methods combined with spermicides can offer some protection against STDs, these combinations may be of special benefit to individuals who have multiple partners. If adherence is a problem (as it can be with OCs, condoms, & diaphragms), use of a long-term method (vaginal contraceptive ring, IUD, Nexplanon, Depo-Provera) can confer more reliable protection.
