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Weight reduction programs designed for a modest weight loss (5%–10%) with the

incorporation of fitness are effective in reducing metabolic disease, cardiovascular

risk, and improving ovulatory potential.

40 A 5% to 10% weight loss in E.F. would be

9 to 18 lb. Diet modification and exercise are the most efficient, cost-effective, and

safe ways to produce weight loss and improve the endocrine and metabolic

parameters of PCOS.

40,44 Weight reduction should be considered first-line therapy in

all overweight or obese women with PCOS, and this should be recommended for

E.F.

IMPACT OF WEIGHT LOSS IN POLYCYSTIC OVARY SYNDROME

A minimum 5% weight loss has consistently demonstrated restoration of regular

menstrual cycling and ovulation in overweight and obese women with PCOS.

15,45,46

When lifestyle modification is implemented, free testosterone concentrations

decrease, but clinical outcomes of acne and hirsutism are not often reported.

15

Obesity in PCOS is associated with a higher risk of developing endometrial cancer,

but very limited evidence exists to determine the impact of weight loss on the

incidence of endometrial cancer.

15 Studies of weight loss in women without PCOS

indicate a 25% to 50% reduced risk of endometrial cancer, so it is logical that

addressing weight reduction may lower that risk as well.

47,48 The Diabetes Prevention

Program trial demonstrated a 53% prevalence of metabolic syndrome; the incidence

of this was reduced 41% in the lifestyle modification group.

49,50 This was

significantly better than treatment with metformin. Studies specifically evaluating

cardiovascular improvements with weight loss in women with PCOS are limited, but

improvements in dyslipidemia and insulin sensitivity have been noted.

DIET COMPOSITION

No single diet has been proven to be ideal for women with PCOS. A diet low in

saturated fat and high in fiber from mostly low-glycemic-index carbohydrate foods

may, however, be suitable and is recommended.

15,51 Glycemic index is a

classification of carbohydrates based on the blood glucose response during 2 hours.

Low-glycemic index foods include bran cereals, mixed grain breads, broccoli,

peppers, lentils, and soy. High-glycemic index foods, or those that should be

minimized, include white rice and bread, potatoes, chips, and foods containing

simple sugars (e.g., juice). It has been shown that in women with PCOS, oral glucose

intake causes larger fluctuations in plasma glucose, increased hyperinsulinemia, and

stimulated adrenal steroid secretion; protein was found to be a preferred nutrient

over glucose.

52 The composition of a diet should be individualized to promote

adherence and achieve specific goals.

EXERCISE

Exercise is a key component in the attainment and maintenance of weight loss.

Exercise with muscle strengthening improves insulin sensitivity.

15 The American

Heart Association recommends 150 minutes/week of moderate exercise or 75

minutes/week of vigorous exercise.

53 E.F. should continue to eat a healthy diet. A diet

consisting of low saturated fats, high fiber, and foods with a low glycemic index

should be encouraged. E.F. should increase her exercise to at least 75 minutes/week

for at least 3 days of the week. If she is going to continue walking as her exercise, she

should walk at a brisk pace. Titrating her time to a goal of exercising 60 minutes

daily will help her lose weight.

Pharmacologic Treatment

CASE 50-1, QUESTION 5: E.F. would like to improve her menstrual irregularity, and be sure that she will

not get pregnant. If possible, she would also like to minimize her hirsutism and acne. What options would be

appropriate to recommend for E.F.?

Several different pharmacologic options could be recommended to E.F (Table 50-

1). A combined oral contraceptive (COC) will address her concerns about irregular

menstruation, hyperandrogenism, and pregnancy prevention. An insulin sensitizer

would improve her menstrual irregularity and possibly reduce her hirsutism and

acne, but it does not address her desire to prevent pregnancy. An antiandrogen, such

as spironolactone, would address only hyperandrogenism, and other agents would

have to be used concurrently to address pregnancy prevention and other hormonal

and metabolic alterations in PCOS.

COMBINED ORAL CONTRACEPTIVES

Estrogen–progestin combination therapy with a COC is the treatment of choice for

women seeking regularity in menstrual cycles and relief from hyperandrogenic

symptoms (see Chapter 47, Contraception, for a list of possible therapies). The

estrogen component suppresses LH, resulting in a reduction of androgen production,

and increases hepatic production of SHBG, thereby reducing free testosterone. The

progestins in various COCs possess variable androgenic effects, so the choice of the

COC may be considered to minimize androgenic exposure. The potential effects of

COCs on insulin resistance, glucose tolerance, and lipids have been debated, do not

appear to increase metabolic risk, and should be considered when choosing a

progestin component.

4,54–56 Caution should be used in those who have insulin

resistance, a high propensity to develop type 2 diabetes, or abnormal lipid profiles.

Combined oral contraceptive therapy in PCOS should be initiated with a

formulation that contains a low dose or very low dose of estrogen (≤35 mcg of

ethinyl estradiol) and a progestin with low androgenic or antiandrogen properties.

Most COCs manufactured today have low or very low estrogen doses. Desogestrel

and norgestimate are progestins with low androgen potential, and drospirenone is an

antiandrogen. A COC containing ethinyl estradiol and desogestrel would prevent

pregnancy, improve menstrual cycle regularity, and reduce E.F.’s signs of

hyperandrogenism (hirsutism and acne). If E.F. desired monthly cycles, she could

take the typical 21/7 regimen (21 days active pill, 7 days inactive pill) or a 24/4

regimen (24 days active pill, 4 days inactive pill). Although not specifically

evaluated in women with PCOS, a monophasic regimen may also be prescribed using

extended cycles of 84 or even 365 days. Extended regimens reduce the number of

cycles/year while providing contraception. Regardless of the COC selected, one of

the long-term benefits is that her risk for endometrial cancer would be reduced by

50%, even up to two decades after discontinuation.

57–59

Ideal initial contraceptive

options for E.F. include 30 to 35 mcg of ethinyl estradiol and a low-androgenic or

nonandrogenic progestin such as drospirenone or desogestrel. If she would like to

have her menstrual cycle monthly, she should take 21 active pills followed by 7

inactive pills. If she does not desire to have her menstrual cycle, then taking

continuous active pills in an extended (daily) manner is most appropriate. This

therapy would address her concerns of menstrual irregularity, contraception,

hirsutism, and acne. She should continue therapy for as long as she desires

contraception and minimization of the androgenic effects of PCOS.

CASE 50-1, QUESTION 6: Two months later, E.F. reports she is experiencing mood swings and weight gain

on her ethinyl estradiol/desogestrel oral contraceptive. She is debating whether she wants to continue with the

COC and would like to explore other treatment possibilities. What other therapy options may be beneficial for

E.F. if she considers this COC to be intolerable?

p. 1011

p. 1012

Table 50-1

Selected Treatment Options for Polycystic Ovary Syndrome (PCOS)

Drug Class

(Example)

Purpose of

Therapy

Mechanism of

Action Effective Dose Side Effects

Combined oral

contraceptive

(estrogen and

progestin)

Menstrual cyclicity,

hirsutism, acne

Suppresses LH (and

FSH) and thus

ovarian androgen

production;

increases sex

hormone–binding

globulin, which

decreases free

testosterone

One tablet orally

daily for 21 (or 24)

days, then 7-day (or

4-day) pill-free

interval

Breast tenderness,

breakthrough

bleeding, mood

swings, libido

changes

Progestins

(medroxyprogesterone)

Menstrual cyclicity Creates withdrawal

bleeding by

transforming

proliferative

endometrium into

secretory

endometrium

5–10 mg orally daily

for 10–14 days

every 1–2 months

Breakthrough

bleeding, spotting,

mood swings

Biguanide (metformin) Impaired glucose

tolerance, type 2

diabetes

Decreases hepatic

glucose production,

secondarily reducing

insulin levels; may

have direct effects

on steroidogenesis

1,500 mg orally daily

in divided doses (up

to 2,550 mg/day)

Gastrointestinal

problems, diarrhea,

abdominal pain

Antiandrogen

(spironolactone)

Hirsutism, acne Inhibits androgens

from binding to

androgen receptor

50–100 mg orally

twice daily

Hyperkalemia,

polymenorrhea,

headache, fatigue

Antiestrogen

(clomiphene citrate)

Ovulation induction Increases GnRH

secretion, which

50 mg orally daily

for 5 days; may

Vasomotor

symptoms,

induces rise in FSH

and LH

increase to 150 mg gastrointestinal

problems

Aromatase inhibitor

(letrozole)

Ovulation induction Blocks estrogen

synthesis to directly

affect

hypothalamic–

pituitary–ovarian

function

2.5 mg orally daily

for 5 days; may

increase to 7.5 mg

FSH, follicle-stimulating hormone; GnRH, gonadotropin-releasing hormone; LH, luteinizing hormone.

Metformin

Metformin inhibits hepatic glucose output, providing lower insulin concentrations

and reducing androgen production in the ovary. Metformin also appears to influence

ovarian steroidogenesis directly.

60,61 Metformin is primarily used for IGT or T2D

related to PCOS. Metformin has minimal effectiveness for hirsutism or acne and was

found to have no benefit improving rate of miscarriage, fertility, or live-birth rates in

anovulatory women with PCOS.

4,62–63

Its routine use for treatment of infertility is not

recommended.

4

In a Cochrane systematic review comparing COCs and metformin,

metformin demonstrated a reduction in fasting insulin and triglyceride levels

compared to oral contraceptives, but greater improvement in menstrual pattern and

serum androgen levels was observed with COCs.

56

The most commonly used and most effective dose of metformin in PCOS is 500 mg

orally 3 times daily (TID). It should be titrated slowly to this effective dose; doses

up to 2,000 mg daily or 2,550 mg daily may be necessary for individual

circumstances. The gastrointestinal (GI) side effects of diarrhea, nausea, vomiting,

and abdominal bloating are usually transient and dose-related, and can be minimized

by taking with food instead. An estimated glomerular filtration rate (eGFR) should be

calculated at least annually in women using metformin because it is contraindicated if

eGFR is <30 ml/min/1.73 m2 and not recommended if eGFR is 30–45 ml/min/1.73

m2

.

AGENTS FOR HIRSUTISM

Although frequently used, antiandrogens do not have FDA-approved uses for the

treatment of female hirsutism or acne in the United States. Spironolactone is

commonly prescribed to women for hirsutism. Drospirenone (a derivative of

spironolactone), found in COCs has antiandrogenic properties and has also been

evaluated in the long-term treatment of hirsutism.

64 Finasteride has been used for

female hirsutism, but its lack of specificity for type I 5α-reductase in the

pilosebaceous unit and toxicity may make this a suboptimal treatment choice.

Flutamide is effective for hirsutism, but it is not used because of hepatotoxicity.

Eflornithine hydrochloride has been approved for topical use in treating facial

hirsutism, but has not been well studied in women with PCOS. Electrolysis and laser

treatments may be acceptable physical approaches to hair removal for women with

PCOS.

Spironolactone

Spironolactone acts by competitively inhibiting dihydrotestosterone (DHT) from

interacting with its androgen receptor. This causes a decrease in activity of ovarianproduced testosterone. Spironolactone reduces hair growth by 40% to 88%;

however, it takes 6 to 9 months for improvement.

65 Spironolactone may be associated

with possible teratogenicity (feminization of the male fetus), so it is prudent to advise

women to avoid pregnancy for at least 4 months after the discontinuation of

spironolactone. It is recommended that spironolactone be used with a COC to avoid

teratogenicity, as well as the side effect of polymenorrhea (more frequent menses)

when used as monotherapy. Spironolactone in combination with a COC would also

improve hormonal and metabolic manifestations of PCOS as well. The usual

effective spironolactone dose is 50 to 100 mg orally twice daily for 6 to 12 months.

Serum potassium and renal function should be monitored because this aldosterone

antagonist can cause hyperkalemia. Furthermore, spironolactone should not be used

with a COC containing drospirenone because of a potential risk for hyperkalemia.

Finasteride

Finasteride is a type II 5α-reductase inhibitor, which decreases the conversion of

testosterone to DHT. It provides an approximate

p. 1012

p. 1013

30% reduction from baseline for hirsutism. Compared with spironolactone,

finasteride is as or less effective in women with hirsutism.

66 The dose of 5 to 7.5 mg

orally daily typically takes 6 months for clinical improvement. It is critical to avoid

pregnancy while taking this drug owing to the potential teratogenic effect of abnormal

genitalia in the male fetus. Finasteride should not be touched or handled by women

who are or may be pregnant. This danger limits the usefulness of finasteride in

women with PCOS because most are of childbearing age or desire pregnancy.

E.F. should be encouraged to continue her COC for at least 3 months as most COC

side effects resolve within 3 months of use. If E.F. decides that the side effects from

the COC are intolerable, an appropriate recommendation for E.F. would be

spironolactone 50 mg orally daily. She should continue this therapy for as long as she

desires the benefits of this therapy, but it will not provide contraception. E.F. should

ensure proper contraception is used while taking spironolactone to avoid

teratogenicity.

CASE 50-1, QUESTION 7: E.F. successfully used oral contraceptives for 7 years. After getting married 3

years ago, E.F. and her husband have decided to have children. She lost 30 lb with diet and exercise when she

got married and has been able to maintain that weight loss. They have been trying to get pregnant for the last 18

months. The reason for infertility has been identified as oligo-ovulation associated with PCOS. What treatments

for ovulation induction should be used in E.F. and why?

Anovulation or oligo-ovulation in women with PCOS is usually first treated with

diet, exercise, and weight reduction. Weight loss improves pregnancy rates and

reduces miscarriage rates in women with PCOS. E.F. has been successful at losing

weight and now must consider agents for ovulation induction.

AGENTS FOR OVULATION INDUCTION

Clomiphene Citrate

Clomiphene citrate induces ovulation via an antiestrogenic effect on the

hypothalamus. GnRH secretion is increased, which increases LH and FSH

production. The increase in FSH concentrations causes appropriate follicle

development and estrogen secretion, which produces a positive feedback on the

hypothalamic–pituitary system to create a LH surge for ovulation.

The usual initial dose of clomiphene citrate is 50 mg orally daily for 5 days,

started on day 5 after a spontaneous or progestin-induced menses. The clinician must

determine whether ovulation occurs with each cycle through laboratory testing,

ultrasound monitoring, or both. If ovulation does not occur, the dose can be increased

by 50 mg orally daily up to 150 mg orally daily; however, doses greater than 100 mg

orally daily for 5 days are not recommended by the manufacturers.

67 A repeat cycle

can be administered as early as 30 days after the previous cycle as long as pregnancy

has not occurred. If conception does not occur, women can use clomiphene for three

to four cycles before considering another regimen. Long-term cyclic therapy is not

recommended beyond a total of six cycles because of potential ovarian cancer risk.

Most women respond to clomiphene citrate within three to four ovulatory cycles, but

5% to 10% have demonstrated clomiphene resistance and need to consider other

options.

67 For women who are clomiphene citrate-resistant, dexamethasone can be

used in conjunction with clomiphene or an aromatase inhibitor can be used (e.g.,

letrozole, anastrozole) as an alternative for infertility in PCOS.

68–71

Aromatase Inhibitors

Letrozole is an aromatase inhibitor which blocks estrogen synthesis to directly affect

hypothalamic–pituitary-–-ovarian function and increase pregnancy rates. Potential

advantages of letrozole over clomiphene citrate include more physiologic hormonal

stimulation of the endometrium, a lower multiple-pregnancy rate through singlefollicle recruitment, a better side-effect profile with fewer vasomotor and mood

symptoms, and more rapid clearance which reduces the chances of periconceptional

exposure.

72

In a study of 750 women with PCOS, letrozole or clomiphene was

provided for up to five cycles whereas ovulation and pregnancy were evaluated.

73

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