A practical guide to prescribing oral contraception

By Jonathan M. Mansbach, MD, and S. Jean Emans, MD

Oral contraceptives are a safe and reliable choice of birth control for most teenage girls. Here's what you need to know to prescribe them appropriately and counsel your patients effectively.

Although it is clearly important for pediatricians to encourage their adolescent patients to postpone sexual activity, they are often called on to provide teens with quality reproductive health care and screening for sexually transmitted diseases (STDs). The 1999 Youth Risk Behavior Survey reports that 33% of girls and 45% of boys in the 9th grade, and 66% of girls and 64% of boys in the 12th grade, have had sexual intercourse.¹ The United States has the highest teen pregnancy rate among developed countries, with almost 1 million pregnancies a year. These figures underscore the importance of knowing how to counsel and provide appropriate care for sexually active adolescents. Here we focus on one important, and commonly encountered, aspect of that care: prescribing oral contraception for teenage girls.

The initial contraceptive visit

Ascertaining whether a patient is sexually active is an important part of the initial office visit. To improve the likelihood that she will discuss sensitive information, it is essential to establish and clarify with the parent and adolescent the concept of confidentiality at the initiation of care or in early adolescence.^2­4 If the patient reveals that she is sexually active, discuss the emotional consequences and risks of sexual activity and methods to reduce risk. Also, remember that many 14- and 15-year-old teens have sex involuntarily, so it is important to discuss coercive sex, especially how to avoid it and how to report it.

Early in the visit, ask a sexually active girl if she has ever used any form of birth control, whether she wants to become pregnant, and if she thinks she can become pregnant. The last question identifies adolescents who may worry about or deny their fertility. Establishing that the patient does not want to become pregnant opens the subject of birth control methods. Some patients may be ambivalent about becoming pregnant; helping them think about life plans ("What do you plan to be doing in one year? In five years?") may help them make thoughtful decisions.

Continue the discussion by asking the patient relevant questions regarding her thoughts about birth control. Weave into this conversation the benefits and drawbacks of existing contraceptive choices, including abstinence, barrier methods, and hormonal methods (oral contraceptives, Depo- Provera, Norplant, Lunelle).

Teens considering oral contraception often have worries based on myths about the method, including that they will have to take drug holidays from the pill, that oral contraceptives (OCs) can cause birth defects or stunt growth, and, most commonly, that they cause weight gain (see "Clearing up the myth of weight gain," below). Teens considering whether to use the pill for birth control also need to know that OCs have health benefits (see "Health benefits of OCs," below).

If the patient chooses oral contraception, begin assessing the appropriateness of this method with the medical history. The history should include current sexual history, past problems with weight gain, acne, headaches, dysmenorrhea, irregular menses, nausea, and abdominal pain.

To help physicians decide whether to prescribe an OC for a given patient and to improve access to this method of birth control, the World Health Organization (WHO) developed medical eligibility criteria for OC use in 1996 and updated them in 2000.⁵ The criteria are available at the WHO Web site, www.who.int . They classify the risk of OC use into four categories:

• Category 1: no restriction on OC use

• Category 2: advantages of an OC generally outweigh risks

• Category 3: risks generally outweigh benefits

• Category 4: OCs are contraindicated.

Table 1details the criteria for WHO categories 3 and 4.

TABLE 1
WHO criteria for prescribing OCs, categories 3 and 4

Hypertension

History of hypertension in which blood pressure (BP) cannot be monitored
Adequately controlled hypertension, where BP can be evaluated
Systolic BP 140–159 mm Hg or diastolic BP 90–99 mm Hg

Diabetes

Diabetes with retinopathy, nephropathy, neuropathy, or other vascular disease (category 3/4)
Diabetes >20 yr duration (category 3/4)
Smoking (>35 yr

Mild cirrhosis

Postpartum
Breastfeeding 6 wk–6 mo (primarily breastfeeding)*

History of breast cancer without evidence of disease for 5 yr

Unexplained suspicious vaginal bleeding (before evaluation)

Long-term use of enzyme-inducing antibiotics or anticonvulsants (rifampin, griseofulvin, phenytoin, carbamazepine)

History of OC–related cholecystitis

Symptomatic biliary tract disease

Known genetic hyperlipidemia, depending on severity

Migraine without focal neurologic symptoms that develops in a woman under 35 yr of age while on OCs

*The American Academy of Pediatrics has approved the use of OCs once lactation is well established. Many consider 6 weeks appropriate. The concern is over thromboembolic events.

Hypertension

Systolic BP >160 mm Hg or diastolic BP >100 mm Hg

Pregnancy

History of or current ischemic heart disease

History of stroke

History of or current deep venous thrombosis or pulmonary embolism

Vascular disease

Complicated valvular heart disease (pulmonary hypertension atrial fibrillation, history of subacute bacterial endocarditis)

Smoking >15 cigarettes/d and age >35 yr

Migraine with focal neurologic symptoms

Major surgery with prolonged immobilization

Current breast cancer

Active viral hepatitis

Severe cirrhosis

Benign or malignant liver tumor (adenoma, hepatoma)

Breastfeeding

A complete physical exam, with emphasis on an accurate blood pressure reading, and, possibly, a pelvic exam, should follow the history. Because fear of a first pelvic exam has been shown to be a barrier to seeking birth control among adolescent girls, delaying the pelvic exam by three to six months or longer can help establish trust between the teen and the physician.^6,7 On the other hand, such a delay may prevent early identification of asymptomatic STDs unless sensitive urine tests are available. [Editor's note: For a discussion of urine-based tests for STDs, see "The future is here: Noninvasive diagnosis of STDs" in the February issue, also accessible at www.contemporarypediatrics.com .] The importance of pelvic exams to reproductive health care should be explained to adolescent girls, regardless of the contraceptive method they choose.

Correct and effective use of an OC by patients who are medically eligible depends on the characteristics of the user, side effects of the formulation chosen, cost of the pill, and ease of access to the pill. Assessing these factors is important because stopping or misusing an OC is a frequent cause of unintended pregnancy in adolescents.⁸ If taken correctly, OCs have a failure rate of less than 1%; for the average user, however, OCs fail approximately 7% of the time during the first year.⁹

How OCs work

Understanding the pathophysiology involved in suppressing ovulation and the pharmacology of OCs is helpful in choosing the appropriate pill. Although there are progestin-only pills, combined contraceptive pills contain both estrogen and progestin. The components work synergistically to suppress ovulation by their hypothalamic and pituitary effects and by progestin-mediated alterations in the cervical mucus and endometrium. More specifically, combined pills suppress ovulation by diminishing the frequency of gonadotropin-releasing hormone (GnRH) pulses, decreasing pituitary responsiveness to GnRH, suppressing the luteinizing and follicle-stimulating hormones, and eliminating the luteinizing hormone surge.

The estrogen in combined OCs is either mestranol or ethinyl estradiol (EE). Mestranol must be converted to EE to be active; 50 µg of mestranol approximates 35 µg of EE.

Classification of progestins is more complex. There are two classes: estranes and gonanes. The estrane progestins are norethindrone, ethynodiol diacetate, and norethindrone acetate. Ethynodiol diacetate and norethindrone acetate are converted to the biologically active compound norethindrone. Gonane progestins are norgestimate, levonorgestrel, and desogestrel. Norgestimate is converted to the biologically active compound levonorgestrel and also to levonorgestrel-3-oxime. Desogestrel is converted to the biologically active 3-keto-desogestrel.

The pharmacologic differences between the two classes of progestins—in terms of bioavailability, serum half-life, and binding affinity—have clinical implications. The higher the bioavailability, the lower the dose of progestin required. The most bioavailableprogestin is levonorgestrel (90%), followed by norethindrone (64%) and desogestrel (62%).¹⁰

The longer the serum half-life of an OC (that is, the time it takes its active constituents to fall to 50% of maximum blood level) the better it controls the cycle, with less breakthrough bleeding, and the greater safety it offers when pills are missed. In general, gonanes have a longer serum half-life than estranes.¹¹

The higher the relative binding affinity of an OC for the progesterone receptor, the lower the dose required to inhibit ovulation. Levonorgestrel has the highest binding affinity, followed by desogestrel and its metabolite.¹²

Types of OCs

OCs are classified in two ways. The first divides OCs into high-dose formulations (containing 50 µg of ethinyl estradiol) and low-dose formulations (containing 20, 30, or 35 µg of ethinyl estradiol or 50 µg mestranol). The second classification is based on whether the estrogen or progestin levels vary or remain constant over the course of the cycle. If the dose of hormone varies over the cycle, the pills are multiphasic (biphasic or triphasic); if the dose is constant through the cycle, the pills are monophasic.

Most OCs are given in a 28-day cycle, with 21 days of pills containing active hormones and seven days of placebo or reminder pills. One type has 26 days of hormone pills and two days of placebo. Monophasic pills can be prescribed continuously in cycles of 84 days (four packs of 21 days) for conditions such as endometriosis and menstrual-related disorders and, sometimes, for convenience.

Choosing an OC is a matter of availability, cost—generic, a brand covered by insurance, or a sample from the family planning clinic, for example—history of the patient's use of OCs, and your clinical experience. Because steroid metabolism varies from woman to woman, it is difficult to predict how an OC will perform. No matter the selection, make every effort to have the patient continue the same pill for a three-month trial because most benign, but annoying, side effects disappear within that time.

Getting started

At least three commonly used timetables exist for starting the first pack of OCs: Sunday after the first day of menses, the first day of menses, or the day of the clinic visit.

The Sunday start was recommended initially so that women would not have their menstrual period on a weekend. The patient takes the first pill the Sunday after the first day of menses; if her menstrual period begins on Sunday, she starts taking the OC that day. The patient should use a backup method of contraception during the first week of pills unless she begins taking the pill on the first day of her menses, in which case backup is not needed. When discussing backup methods of contraception, remind teens that OCs do not prevent STDs.

A newer option is to start the OC the day of the office visit. This approach has drawbacks: It may result in more breakthrough bleeding, and a very early pregnancy could be missed for several weeks.

When starting an adolescent on an OC, remember to demonstrate how to use the pill packages. Spending a few moments explaining the packaging reduces confusion.

A missed pill is a common problem. What to do in this situation depends on the number and timing of missed pills. In general, the risk of pregnancy increases most significantly after three or more pills are missed, although little data exist on pills that contain 20 µg of ethinyl estradiol.

Side effects: Bleeding and nausea

One of the most common side effects of OCs is breakthrough bleeding. With low-dose OCs, the rate of breakthrough bleeding is between 10% and 30% during the first month, decreasing over the first three cycles. In two randomized studies comparing OCs containing 20 µg and 35 µg ethinyl estradiol, the rate of breakthrough bleeding was higher in the first cycle for one of the 20-µg pills but similar across all formulations at the end of six months.^13,14

Because breakthrough bleeding is a major reason why women stop taking OCs, patients should be counseled about this side effect during the initial clinic visit.¹⁵ If bleeding occurs in the initial cycles, reassure and observe. Other common causes of breakthrough bleeding to consider include missed pills, STDs (especially chlamydial infection), and pregnancy.

If bleeding is heavy for two or three days or continues for longer than five days, several methods can be prescribed to address it if necessary. One easy method is for the patient to take an additional pill from a different package of pills approximately 12 hours after the regularly scheduled time until the bleeding stops. Another approach is to add 20 µg of ethinyl estradiol to the regimen 12 hours after taking the scheduled pill for one week at the first sign of bleeding. If bleeding persists for longer than three months, is bothersome, and cannot be attributed to a cause other than the OC, switching to a pill with a higher dosage of estrogen (rarely higher than 35 µg) or a different progestin (gonane) is appropriate in an effort to stabilize the endometrium.

Nausea is related to the estrogen content of OCs. To minimize it, advise patients to take the pill after dinner, or with a snack before bedtime. As with most other side effects, nausea is likely to subside after several weeks. If a patient cannot tolerate the nausea, switching to a pill containing a lower dose of estrogen may help. Decreasing the dose of estrogen may, however, increase the likelihood of breakthrough bleeding. Other causes of nausea also must be considered because not all concomitant symptoms are necessarily caused by the OC.

Blood pressure changes

Rarely, low-dose OCs can mildly elevate blood pressure (BP). A large prospective study found 41.5 cases of elevated BP for every 10,000 person years studied.¹⁶ The pathophysiology of OC­induced hypertension continues to be debated, but some evidence suggests that estrogen increases the activity of the renin-angiotensin system.¹⁷ Adolescents on an OC need to have their BP monitored. In our clinic, we check BP at the initial visit, at three months, and every six to 12 months thereafter.

If hypertension develops, the WHO criteria outlined in Table 1 provide guidance about the risk of continuing to prescribe an OC. Since the WHO guidelines give BP ranges for adults, not adolescents, pediatricians should use pediatric BP guidelines based on age and height. A lower-dose (20-µg) pill may be tried for a teen who develops mild hypertension. If BP is significantly elevated, discontinue the OC and prescribe an alternative, such as progestin-only pills.

Headache: Reason to be cautious?

Headaches are common in adolescents, and OCs may either alleviate or exacerbate them. During the initial visit, ask about headaches and, if present, document their frequency, type, and severity. Concern has been raised about the risk of stroke among patients who have headaches and take an OC. In general, OCs do not increase the risk of stroke in healthy, nonsmoking women under 35 years of age,^18,19 but the data on migraine are more complicated.

WHO guidelines classify patients under 35 years of age who have migraine without aura as category 2. Women who develop migraine without aura while they are taking OCs are classified as category 3. The United Kingdom Family Planning Association has suggested that, for women with migraine without aura who have one additional risk factor for stroke, the risk of an OC may outweigh its benefits (WHO category 3). If two additional risk factors are present, an OC is contraindicated (WHO category 4).²⁰ Those risk factors are age over 35 years, diabetes, smoking, obesity with a body mass index greater than 30, hyperlipidemia, hypertension, and arterial disease in a family member under 45 years of age. Combined OCs should not be prescribed (WHO category 4) for women who have migraine with focal neurologic symptoms during the headache, such as significant visual disturbances or hemiparesis.

Generally, a pill lower in estrogen should be prescribed for women with migraine. Another alternative for women with migraine is a progestin-only OC or progestine-only injectable (Depo-Provera). Instruct these patients to call your office if they have a severe headache or acute visual disturbances while taking an OC. Note that, in some women, migraine—especially menstrual migraine—may improve with an OC.

Venous thromboembolism

The true risk of venous thromboembolism (VTE) for women on OCs is another controversy. The Food and Drug Administration (FDA) estimated in 1995 that the annual risk of nonfatal VTE is four in 100,000 among healthy women; 10 to 15 in 100,000 among women taking an OC that contains norethindrone or levonorgestrel; 20 to 30 in 100,000 among women taking an OC that contains desogestrel or gestodene; and 60 in 100,000 among pregnant women.²¹ There has been much debate over potential bias in the epidemiologic studies that demonstrated an increased risk of thromboembolism among women taking an OC containing desogestrel or gestodene. A study of 230,000 15- to 44-year-old women enrolled in the Medicaid program in Michigan showed no increase in the risk of deep venous thromboembolism in patients taking less than 50 µg of estrogen.²²

The most common congenital defect associated with VTE is the Factor V Leiden mutation, which renders the procoagulant Factor V relatively resistant to degradation by activated protein C. The carrier frequency of this mutation is 5.3% among Caucasian Americans, 2.2% among Hispanic-Americans, 1.2% among African-Americans, and 0.45% among Asian-Americans.²³ Another common gene mutation, prothrombin G20210A, is found in 3% to 4% of Caucasian Americans.²⁴ Rarer causes for VTE include protein C deficiency, protein S deficiency, antithrombin III deficiency, and the presence of antiphospholipid antibodies. Despite the discovery of these causes, the specific cause of most cases of VTE is unknown. In one study of women with VTE, 70% had no defined cause.²⁵

If a patient has a strong family history of VTE, you can provide initial screening by testing her or, preferably, the proband for Factor V Leiden and G20210A mutations. If these tests are normal in a patient with a worrisome family history, discuss the risks of VTE associated with OCs compared to the risk of VTE during pregnancy.

Despite the conflict over the epidemiologic data and the physiologic mechanism of VTE, patients should be counseled about the risks and symptoms of thromboembolism. Although it is impossible to determine which patients will develop this very rare complication, do not prescribe an OC for those with a personal history of VTE. Patients with a strong family history of thrombosis should be screened medically for clotting disorders and counseled about the increased risks associated with OCs. Such patients should use a progestin-only pill or other method of contraception.

Emergency contraception

All adolescents should be knowledgeable about emergency contraception (EC), which can be used within 72 hours after unprotected intercourse. The earlier the first dose is administered, the greater the efficacy. The two main EC regimens are Yuzpe and progestin only, or Plan B.

Yuzpe. This regimen has been prescribed most often and consists of 100 µg of ethinyl estradiol and 1.0 mg norgestrel followed, 12 hours later, by the same dose. An easy, accessible EC method for clinicians to prescribe is the Preven pack, which contains an education booklet, a pregnancy test, and the required medication. Table 2 lists acceptable pill combinations for EC. On the basis of a meta-analysis, the effectiveness of Yuzpe is estimated to be 74% (95% confidence interval, 62.9% to 79.2%).²⁶

TABLE 2
Emergency contraception alternatives (Yuzpe)

The only absolute contraindication to Yuzpe is known pregnancy. Some believe that migraine at presentation and a history of thromboembolism also are contraindications. Insufficient evidence exists to support the other contraindications listed on the label, including ischemic heart disease, stroke, migraine, liver tumor, breast cancer, and past breast biopsy.

The two most common side effects of Yuzpe are nausea and vomiting. Pretreatment with an antiemetic, one hour before the first dose, can help prevent them. Meclizine, an over-the-counter antiemetic, reduced nausea and vomiting associated with the regimen in a clinical trial.²⁷

Plan B. This regimen uses only the progestin levonorgestrel. The dose is 0.75 mg levonorgestrel at presentation, repeated 12 hours later. Plan B is more effective than Yuzpe and has fewer side effects. A randomized trial of the two methods demonstrated that Plan B prevented 85% of expected pregnancies, compared to 57% prevented by Yuzpe.²⁸ Because Plan B contains no estrogen, the only contraindication is known pregnancy or hypersensitivity to one of the components of the pill. The FDA approved the regimen in July 1999 but, despite its effectiveness, its availability is still limited to health departments, college health services, some hospitals, and a few pharmacies.

Don't forget about STDs

It is important to reiterate to patients during contraceptive visits that condoms, not OCs, protect against sexually transmitted disease. Latex and latex-free condoms are available, but latex condoms are the most widely sold. Be sure to tell patients not to use petroleum-based lubricants such as Vaseline with latex condoms; instead, they should choose a water-based product such as K-Y Jelly or Surgilube.

Birth control—and more

Because many teenagers have had sexual intercourse by the time they complete high school, it is important for physicians who treat adolescents to become comfortable talking to them about abstinence and birth control. Oral contraceptives are a reliable, safe choice of birth control for most teens. No matter what birth control method a teen chooses, the contraceptive visit offers physicians many teachable moments to provide counseling about sexual activity, its consequences, and how to practice safe sex. For sources of information about reproductive health and contraception for teenagers, see "Resources," below.

REFERENCES

1. MacKay AP, Fingerhut LA, Duran CR: Adolescent Health Chartbook. Health, United States 2000. Hyattsville, Md., National Center for Health Statistics, 2000

2. Ford CA, Millstein SG, Halpem-Feilsher BL, et al: Influence of physician confidentiality assurances on adolescents' willingness to disclose information and seek future health care. JAMA 1997;278:1029

3. Cheng TL, Savageau JA, Sattler AL, et al: Confidentiality in health care: A survey of knowledge, perceptions, and attitudes among high school students. JAMA 1993;269:1404

4. Thrall JS, McCloskey L, Ettner SL, et al: Confidentiality and adolescents' use of providers for health information for pelvic examinations. Arch Pediatr Adolesc Med 2000;154:885

5. World Health Organization, Family and Reproductive Health Programme: Improving Access to Quality Care in Family Planning. Medical Eligibility Criteria for Contraceptive Use, ed 2. Geneva, World Health Organization, 2000

6. Zabin LS, Stark HA, Emerson MR: Reasons for delay in contraceptive clinic utilization. J Adolesc Health 1991;12:225

7. Armstrong KA, Stover MA: Smart start: An option for adolescents to delay the pelvic examination and blood work in family planning clinics. J Adolesc Health 1994;15:389

8. Rosenberg MJ, Waugh MS, Long S: Unintended pregnancies and use, misuse, and discontinuation of oral contraceptives. J Reprod Med 1995;40:335

9. Fu H, Darroch JE, Haas T, et al: Contraceptive failure rates: New estimates from the 1995 National Survey of Family Growth. Fam Plann Perspect 1999;31:58

10. Stanczyk FZ, Roy S: Metabolism of levonorgestrel, norethindrone, and structurally related contraceptive steroids. Contraception 1990;42:67

11. Perone N: The progestins, in Goldzieher JW, Fotherby K (eds): Pharmacology of the Contraceptive Steroids. New York, Raven Press, 1994, pp 5­19

12. Juchem M, Pollow K, Elger W, et al: Receptor binding of norgestimate—a new orally active synthetic progestational compound. Contraception 1993;47:283

13. Rosenberg MJ, Meyers A, Roy V: Efficacy, cycle control, and side effects of low- and lower-dose oral contraceptives: A randomized trial of 20-microgram and 35-microgram estrogen preparations. Contraception 1999;60(6):321

14. Reisman H, Martin D, Gast MJ: A multicenter randomized comparison of cycle control and laboratory findings with oral contraceptive agents containing 100 µg levonorgestrel with 20 µg ethinyl estradiol or triphasic norethindrone with ethinyl estradiol. Am J Obstet Gynecol 1999;181(5 Pt 2):45

15. Rosenberg MJ, Waugh MS: Oral contraceptive discontinuation: A prospective evaluation of frequency and reasons. Am J Gynecol 1998;179:577

16. Chasan-Taber L, Willet WC, Manson JE, et al: Prospective study of oral contraceptives and hypertension among women in the United States. Circulation 1996; 94:483

17. Byrne KB, Geraghty DP, Stewart BJ, et al: Effect of contraceptive steroid and analapril treatment on systolic blood pressure and plasma reninangiotensin in the rat. Clin Exp Hypertens 1994;16(5):627

18. Petitti DB, Hunter JR, Jick H, et al: Stroke in users of low-dose oral contraceptives. N Engl J Med 1996;335:8

19. WHO collaborative study of cardiovascular disease and steroid hormone contraception: Ischaemic stroke and combined oral contraceptives: Results of an international, multicentre, case-control study. Lancet 1996;348:498

20. MacGreger EA, Guillebaud J, and the Clinical and Scientific Committee of the Faculty of Family Planning and Reproductive Health Care and the Family Planning Association: Recommendations for clinical practice. Combined oral contraceptives, migraine, and ischaemic stroke. Br J Fam Plann 1998;24:55

21. Food and Drug Administration: Oral contraceptives and the risk of blood clots. FDA Talk Paper November 24, 1995

22. Gerstman BB, Piper JM, Tomita DK, et al: Oral contraceptives, estrogen dose, and the risk of deep venous thromboembolic disease. Am J Epidemiol 1991;133:32

23. Ridker PM, Miletich J, Hennekens CH, et al: Ethnic distribution of Factor V Leiden in 4,047 men and women. JAMA 1997;277:1305

24. Frenkel EP: Prothrombin G20210A gene mutation, heparin cofactor II defects, primary (essential) thrombocythemia, and thrombohemorrhagic manifestations. Semin Thromb Hemost 1999;25(4):375

25. Winkler UH: Blood coagulation and oral contraceptives: A critical review. Contraception 1998;57:203

26. Trussell J, Rodriguez G, Ellertson C: Updated estimates of the effectiveness of the Yuzpe regimen of emergency contraception. Contraception 1999;59:147

27. Raymond EG, Creinin MD, Barnhart KT, et al: Meclizine for prevention of nausea associated with use of emergency contraceptive pills: A randomized trial. Obstet Gynecol 2000;95:271

28. Task Force on Postovulatory Methods of Fertility Regulation: Randomised controlled trial of levonorgestrel versus the Yuzpe regimen of combined oral contraceptives for emergency contraception. Lancet 1998; 352:428

DR. MANSBACH is a fellow in the division of adolescent/young adult medicine, Harvard Medical School, Children's Hospital, Boston.

DR. EMANS is chief, division of adolescent/young adult medicine; co-director, Center for Young Women's Health; and professor of pediatrics, Harvard Medical School, Children's Hospital, Boston. She is a member of the Wyeth Lederle speaker's bureau and has received educational grants from Wyeth Lederle, Ortho, Pfizer, and Parke-Davis. This work was supported in part by the project #6T71 MC 00009-09 S1 R0 from the Maternal and Child Health Bureau (Title V, Social Security Act), Health Resources and Services Administration, US Department of Health and Human Services.

Clearing up the myth of weight gain

Many adolescents considering taking an OC are concerned about gaining weight as a side effect.^1,2 Progestins can increase appetite, but evidence suggests that the majority of teens on an OC stay within two pounds of their baseline weight. Moreover, just as many adolescents lose weight as gain weight while on an OC.³

A patient who is convinced that she has gained weight from taking an OC should come to the office for a weight check and, if indicated, nutrition and exercise counseling. If the problem persists, a change to an OC with lower estrogen and progestin content may help.

REFERENCES

1. Emans SJ, Grace E, Woods ER, et al: Adolescents' compliance with the use of oral contraceptives. JAMA 1987;257:3377

2. Herold ES, Goodwin MS: Perceived side effects of oral contraceptives among adolescent girls. Can Med Assoc J 1980;123:1022

3. Rosenberg M: Weight change with oral contraceptive use and during the menstrual cycle. Results of daily measurements. Contraception 1998;58:345

Health benefits of OCs

Oral contraceptives have many health benefits that should be reviewed with patients who are considering using the pill. Because OCs inhibit ovulation, they provide some protection against ovarian cancer and ectopic pregnancy. One study reported a 40% decrease in the future likelihood of ovarian cancer among women who had ever taken an OC.¹ Another study demonstrated a 60% to 80% reduction in ovarian cancer among women who had taken an OC for seven years or more.² A significant reduction in the risk of endometrial cancer also has been noted. Moreover, the regulation of menses by an OC improves heavy, irregular menstruation and primary dysmenorrhea and reduces the likelihood of iron deficiency anemia.

OCs also decrease the risk of hospitalization due to pelvic inflammatory disease. This protective effect is believed to result from progestin's ability to thicken the cervical mucus, preventing the ascent of microorganisms into the upper vaginal tract. Nevertheless, patients should be warned to report severe abdominal pain and reminded to use condoms.

In addition to these health benefits, OCs can be used to treat many common medical conditions, including endometriosis, hypoestrogenic amenorrhea, dysfunctional uterine bleeding, some menstrually related conditions, and heavy menstrual bleeding caused by bleeding disorders. A number of studies have demonstrated that women with polycystic ovary syndrome benefit from taking an OC to reduce circulating androgens. [Editor's note: For more on this topic, see "Amenorrhea and acne in the adolescent girl: Is it polycystic ovary syndrome?" in the October 2000 issue, also accessible at www.contemporarypediatrics.com .] OCs decrease androgen production from ovarian, adrenal, and peripheral sources and increase sex hormone binding globulin, which binds testosterone. They also inhibit the activity of 5a-reductase in hair follicles and the skin, decreasing the conversion of free testosterone to dihydrotestosterone. The latter effect may be particularly important in improving acne and hirsutism.^3­5 Although all OCs should produce similar outcomes, some manufacturers have performed placebo-controlled clinical trials to demonstrate the efficacy of particular OCs for treating acne.

REFERENCES

1. The Cancer and Steroid Hormone Study of the Centers for Disease Control and the National Institute of Child Health and Human Development: The reduction in risk of ovarian cancer associated with oral contraceptive use. N Engl J Med 1987;316:650

2. Schlesselman JJ: Cancer of the breast and reproductive tract in relation to the use of oral contraceptives. Contraception 1989;40:1

3. American College of Obstetricians and Gynecologists: Evaluation and treatment of hirsute women. ACOG Technical Bulletin 1995;203

4. Redmond GP, Olson WH, Lippman JS, et al: Norgestimate and ethinyl estradiol in the treatment of acne vulgaris: A randomized, placebo-controlled trial. Obstet Gynecol 1997;89:615

5. Thomeycroft IH, Stancyk FZ, Bradshaw KD, et al: Effect of low-dose oral contraceptives on androgenic markers and acne. Contraception 1999;60:255

Resources on contraception and reproductive health

Free Web sites that offer information include:

• www.youngwomenshealth.org ; provides teens with excellent information about young women's health issues in English and Spanish.

• www.teenwire.org ; a Planned Parenthood site for teens, includes some articles in Spanish.

• www.teenpregnancy.org ; run by the National Campaign to Prevent Teen Pregnancy, provides information for teens, parents, health-care providers, and educators in English and Spanish.

• www.not-2-late.com ; provides information about emergency contraception in English, Spanish, and French for teens and health-care providers.

In addition, many excellent resource materials for teens, parents, health-care providers, and educators are available from:

The National Campaign to Prevent Teen Pregnancy,
1776 Massachusetts Ave, NW; Suite 200;
Washington, D.C. 20036.

 

Jonathan Mansbach, S. Jean Emans. A practical guide to prescribing oral contraception. Contemporary Pediatrics 2001;10:111.