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PUBERTY
93
infiltrative lesions, irradiation, infection, or neurofibromatosis. Treatment targets the specific
pathologic process and may include surgical intervention, radiation therapy, or GnRH agonists.
13. What are the causes of GnRH-independent precocious puberty, and how are they
treated?
The causes of GnRH-independent precocious puberty can be separated by origin.
• Gonadal causes
• Functional ovarian follicular cysts: the most common cause of GnRH-independent precocious
puberty. These cysts are usually self-limited, and bone age is usually not advanced.
• Ovarian tumors: most commonly granulosa cell tumors (which secrete estradiol), but also
Leydig cell tumors and gonadoblastomas. These tumors are treated surgically.
• McCune-Albright syndrome: caused by a G-protein mutation that leads to continuous
endocrine activation. The most common manifestations are precocious puberty, café-au-lait
spots, and polyostotic fibrous dysplasia of the bone. Patients may also have gigantism, Cushing
syndrome, thyrotoxicosis, or adrenal hyperplasia. Treatment is aimed at blocking estrogen
production with aromatase inhibitors such as testolactone or letrozole or blocking the effects of
estrogen with a selective estrogen receptor modulator (SERM) such as tamoxifen. Bisphospho-
nates may also be useful for polyostotic fibrous dysplasia.
• Adrenal causes
• Adrenal androgen-secreting tumors and congenital adrenal hyperplasia (CAH): Tumors are
surgically excised, and CAH is treated with glucocorticoids.
• Ectopic causes
• Human chorionic gonadotropin (hCG)–secreting tumors are treated surgically.
• Exogenous causes
• Young children are extremely sensitive to the effects of low levels of estrogen, and exposure to
exogenous estrogens in medications, personal care products, and environmental pollutants
may cause precocious puberty. Treatment consists of removing the offending agent.
14. What is the only form of precocious puberty in which bone age is delayed instead
of advanced?
Severe primary hypothyroidism can cause precocious puberty through high serum levels of thyroid-
stimulating hormone, which is structurally similar to FSH. Girls may present with breast development,
galactorrhea (thyrotropin-releasing hormone stimulates prolactin secretion), and menstrual bleeding in
the setting of delayed bone age.
15. What are the essential parts of the history and physical examination in a patient
with precocious puberty?
The history should focus on the timeline of pubertal changes, family history of pubertal milestones or any
reproductive abnormalities, possible exposure to medications or environmental estrogens, history of trauma
or central nervous system (CNS) insults, and any symptoms of thyroid disease, CNS lesions (headaches,
seizures), or abdominal pain. The physical examination should include measurements of height and weight,
as well as a review of growth charts with calculation of the patient’s percentile for age and growth velocity
(cm/year). Tanner staging should be performed along with a skin examination for acne or café-au-lait spots,
and potential masses should be ruled out with thyroid, neurologic, abdominal, and pelvic examinations.
16. What laboratory and imaging studies should be ordered?
• The most important primary test is a bone age radiograph of the left hand and wrist to assess
for increased skeletal maturity.
• FSH and LH should be evaluated; prepubertal levels of FSH are typically higher than LH levels, and
this situation is reversed in puberty. A GnRH stimulation test can differentiate between GnRH-
dependent and GnRH-independent causes—after stimulation, LH is elevated in GnRH-dependent
precocious puberty.
• In girls with GnRH-dependent precocious puberty, a magnetic resonance imaging (MRI) scan of
the head is indicated, as well as possibly thyroid function tests if clinically indicated.
• In girls with GnRH-independent precocious puberty (normal basal and stimulated LH levels), labora-
tory workup should include serum estradiol, testosterone and hCG, dehydroepiandrosterone
sulfate (DHEA-S; adrenal production can result in premature adrenarche), 17-hydroxyprogesterone
(CAH), and late afternoon cortisol (Cushing syndrome).
• A pelvic ultrasound scan should be obtained in all girls with precocious puberty to evaluate for
functional ovarian cysts or tumors. Prolonged or repeated exposure to sex steroids can induce
secondary premature maturation of the HPO-gonadal axis.
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REPRODUCTIVE ENDOCRINOLOGY
17. What effect does estrogen have on bone?
Estrogen increases linear bone growth in the axial skeleton but promotes epiphyseal plate closure
in long bones. Patients with precocious puberty therefore have an initial growth advantage, but they
ultimately have short stature if the condition is left untreated.
18. How can delayed puberty be classified, and what are the most common causes?
• Hypergonadotropic hypogonadism (increased FSH, decreased estradiol): 43% of cases
• Ovarian failure: 65% will have an abnormal karyotype, Turner syndrome being the most
common. Other causes of gonadal failure include idiopathic conditions, iatrogenic causes
(e.g., gonadectomy or gonadotoxic chemotherapy), congenital abnormalities, and genetic
abnormalities (Table 21-2).
• Hypogonadotropic hypogonadism (decreased FSH, decreased estradiol): 31% of cases
• The most common cause is functional GnRH deficiency, which can result from physiologic
delay, malnutrition (e.g., anorexia nervosa), chronic illness, or excessive exercise. Other causes
include hypothalamic or pituitary tumors, hypothyroidism, hyperprolactinemia, pituitary failure,
or genetic defects such as Kallmann syndrome.
• Eugonadism (normal FSH and estradiol): 26% of cases
• Congenital malformation (e.g., müllerian agenesis, imperforate hymen, transverse vaginal
septum). These patients experience breast development but have primary amenorrhea.
• Androgen insensitivity syndrome
19. What are the components of the diagnostic workup of a patient with delayed
puberty?
The history and physical examination should be used to evaluate breast development (a sign of
estrogen exposure), height and weight, the presence or absence of a uterus, diet and exercise habits,
systemic illnesses, medications, and timing of a growth spurt if one has occurred (a late growth spurt
can indicate constitutional delay). A family history should focus on the pubertal history of siblings and
parents, their reproductive history, and the presence of any chromosomal abnormalities. Neurologic
symptoms (e.g., headache, visual disturbances, seizures) suggest a CNS disorder and prompt a visual
field evaluation. Anosmia is suggestive of Kallmann syndrome (congenital GnRH deficiency caused by
a variety of genetic mutations).
Initial laboratory studies should include prolactin, thyroid function tests, FSH, LH, and estradiol.
A low to low-normal FSH level in the setting of a low estradiol level is diagnostic of hypogonadotropic
hypogonadism, and further diagnostic testing such as an MRI scan of the head and adrenal laboratory
studies should be performed to determine the cause. A high FSH level in the setting of a low estradiol
level is diagnostic of hypergonadotropic hypogonadism, and in these cases a karyotype should be
obtained.
Table 21-2. Causes of Delayed Puberty
HYPOGONADOTROPIC
HYPOGONADISM
(↓FSH, ↓ESTRADIOL)
HYPERGONADOTROPIC
HYPOGONADISM
(↑FSH, ↓ESTRADIOL)
EUGONADISM
(NORMAL FSH,
NORMAL ESTRADIOL)
Constitutional delay
GnRH deficiency (Kallmann syndrome)
Weight loss, excessive exercise, or
anorexia nervosa
Pituitary insufficiency
Prolactinoma
Hypothyroidism
Congenital adrenal hyperplasia
Craniopharyngioma
Cushing syndrome
Congenital CNS defects
Other hypothalamic or pituitary tumors
Turner syndrome (or mosaicism)
Ovarian destruction
Pure gonadal dysgenesis
Swyer syndrome (46XY)
17-hydroxylase deficiency
X chromosome deletion
FSH receptor defect
Myotonic dystrophy
Müllerian agenesis
Transverse vaginal septum
Androgen insensitivity
syndrome
Imperforate hymen
CNS, Central nervous system; FSH, follicle-stimulating hormone; GnRH, gonadotropin-releasing hormone.
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B
iBliography
1. Frisch RE, Revelle R. Height and weight in menarche and a hypothesis of menarche. Arch Dis Child. 1971;46:695.
2. Fritz MA, Speroff L, eds. Clinical Gynecologic Endocrinology and Infertility. 8th ed. Philadelphia: Lippincott Williams &
Wilkins; 2011.
3. Herman-Giddens ME, Slora EJ, Wasserman RC, et al. Secondary sexual characteristics and menses in young girls seen
in office practice: a study from the Pediatric Research in Office Settings network. Pediatrics. 1997;99:505–512.
4. Kaplowitz PB, Oberfield SE. Reexamination of the age limit for defining when puberty is precocious in girls in the United
States: implications for evaluation and treatment. Pediatrics. 1999;104:936–941.
5. Lentz GM, Lobo RA, Gershenson DM, Katz VL, eds. Comprehensive Gynecology. 6th ed. Philadelphia: Mosby; 2013.
6. Marshall WA, Tanner JM. Variations in the pattern of pubertal changes in girls. Arch Dis Child. 1969;44:291–303.
KEY POINTS: PUBERTY
1. In girls, the order of puberty is thelarche (breast budding), pubarche (pubic hair), maximum growth
velocity, and then menarche (onset of menses).
2. Tanner stages are a uniform way to describe breast and pubic hair development.
3. Estrogen increases axial bone growth but fuses epiphyseal plates of long bones. This leads to short
stature in patients with untreated precocious puberty.
4. Puberty is considered precocious when thelarche or adrenarche begins before the age of 6 years in
African-American girls or the age of 7 years in white girls.
5. Puberty is considered delayed when girls have no secondary sexual characteristics by the age of
13 years or no menses by 15 years of age in the presence of normal secondary sexual characteristics.
6. Precocious puberty is idiopathic in 75% to 90% of girls.
7. The most common causes of delayed puberty are gonadal dysgenesis (Turner syndrome), constitu-
tional delay, and müllerian agenesis.
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1. What is amenorrhea?
Amenorrhea is the absence of menstruation in a woman of childbearing age. It is divided into two
types: primary and secondary.
2. What is the difference between primary and secondary amenorrhea?
• Primary amenorrhea is defined as the initial absence of menstruation by age 15 years in the
presence of secondary sexual characteristics (breast development, pubic hair, growth acceleration),
or within 5 years of initial breast development (see Chapter 21). The incidence of primary amenor-
rhea is 0.1%.
• Secondary amenorrhea is defined as the absence of menses for longer than 6 months or the
absence of menses for at least three previous cycle intervals in a woman who was previously
menstruating. The incidence of secondary amenorrhea is 0.7%.
3. What are the most common causes of primary amenorrhea?
The most common cause of primary amenorrhea is gonadal dysgenesis, such as in Turner syndrome.
This accounts for more than 40% of cases. Müllerian agenesis (Mayer-Rokitansky-Küster-Hauser Syn-
drome) is the second most common cause, accounting for 15% of patients with primary amenorrhea.
4. What is the most common cause of secondary amenorrhea?
Pregnancy.
5. How can the causes of amenorrhea be categorized?
The causes of amenorrhea can be categorized as disorders of the following:
• Uterus or outflow tract
• Ovary
• Pituitary
• Hypothalamus or central nervous system
• Endocrine system
Table 22-1 is an overview of the causes of primary and secondary amenorrhea.
6. What are the first steps in determining the cause of amenorrhea?
A careful history and physical examination are the first steps to narrow the differential diagnosis.
Pregnancy should always be excluded. The following should be considered:
• Does the patient have evidence of normal pubertal development? Breast development signals
exposure to estrogen, and normal pubic or axillary hair signifies androgen production or exposure.
• Is the reproductive tract normal on examination?
• Is any evidence of hirsutism, excess androgens, or excess cortisol present?
• Does the patient have a history of emotional, physical, or nutritional stress?
• Are any signs of a hypothalamic or pituitary problem noted? Ask whether the patient has had any
headaches, seizures, visual field defects, vomiting, changes in sleep or appetite, or galactorrhea.
• Is the patient taking any medications, or has she received chemotherapy or radiation therapy?
7. What initial blood tests should be performed in a patient with amenorrhea?
• A pregnancy test is performed.
• Thyroid function tests are used to rule out hypothyroidism.
• Prolactin level: Evaluate for hyperprolactinemia, which can occur even in the absence of galactor-
rhea. If hyperprolactinemia is identified, a magnetic resonance imaging (MRI) scan of the brain with
intravenous (IV) contrast should be performed to rule out a prolactinoma.
• Follicle-stimulating hormone (FSH) level: Determine whether failure of the hypothalamic-pituitary
axis or ovary exists. High FSH levels indicate that the hypothalamus is functioning properly but with
no feedback inhibition response from the ovaries. This condition indicates primary ovarian failure.
Low or low-normal levels of FSH indicate hypothalamic dysfunction.
CHAPTER 22
AMENORRHEA
Michelle S. Özcan, MD, and Travis W. McCoy, MD
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AMENORRHEA
97
8. In what two syndromes does the patient have breast development but no uterus
is present?
1. In müllerian agenesis, the ovaries develop appropriately but the uterus does not; sometimes the
vagina is absent as well. Because of the presence of estrogen, breast development is normal. Associ-
ated renal anomalies are common (horseshoe kidney, pelvic kidney, unilateral renal agenesis, ureteral
duplication) and should be ruled out with a renal ultrasound scan or intravenous pyelography.
2. In androgen insensitivity syndrome (AIS), an X-linked recessive defect exists in androgen
receptors. This disorder causes genotypic males (46 XY) to be phenotypically female because
Table 22-1. Common causes of Primary and Secondary Amenorrhea
Common Causes of Primary Amenorrhea
CATEGORY APPROXIMATE FREQUENCY (%)
Absent Breasts and Increased FSH 40
45 X and variants 20
46 XX 15
46 XY 5
Absent Breasts and Low or Normal FSH 30
Constitutional delay 10
Prolactinoma 5
PCOS 3
Stress or anorexia 3
CAH 3
Kallmann syndrome 2
Breast Development Present 30
Müllerian agenesis 10
Androgen insensitivity 9
Constitutional delay 8
Transverse vaginal septum 2
Imperforate hymen 1
Common Causes of Secondary Amenorrhea
CATEGORY APPROXIMATE FREQUENCY (%)
Low or Normal FSH 66
Chronic anovulation (PCOS)
Hypothyroidism
Hyperprolactinemia
Other pituitary tumor/disorder
Cushing syndrome
Weight loss/anorexia
Nonspecific hypothalamic
Ovarian Failure (High FSH) 12
46 XX
Abnormal karyotype
Anatomic 7
Asherman syndrome
Hyperandrogenic States 2
Ovarian tumor
Nonclassic CAH
Undiagnosed Conditions
Data from Current evaluation of amenorrhea. ASRM educational bulletin. Fertil Steril. 2008;90:S219-S225.
CAH, Congenital adrenal hyperplasia; FSH, follicle-stimulating hormone; PCOS, polycystic ovarian syndrome.
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REPRODUCTIVE ENDOCRINOLOGY
target tissues cannot respond to circulating androgens (female external genital development is
the default). These patients have gonads, and male levels of testosterone and dihydrotestosterone
are present. Wolffian duct development, however, fails to occur because of the receptor defect.
Müllerian structures (uterus and upper vagina) also do not develop because antimüllerian hor-
mone (AMH) is still produced by the gonads. Patients have a 20% chance of gonadal malignancy
(dysgerminoma or gonadoblastoma), and the gonads should be removed after the patient reaches
sexual maturity. Breast development occurs normally because of estrogen produced by the
peripheral conversion of androgens. The absence of androgen action results in absent or scant
pubic and axillary hair.
9. What tests should be performed on an otherwise normal 15-year-old girl with
primary amenorrhea with no evidence of breast growth or pubic hair? (The vagina
and uterus are present.)
An absence of breast development indicates a lack of estrogen, so an FSH level is needed.
• Elevated FSH (hypergonadotropic hypogonadism) indicates gonadal failure. A karyotype should
be performed and often shows an X chromosome abnormality, the most common being Turner
syndrome. These patients should have an electrocardiogram, chest radiography, intravenous
pyelography, and thyroid function tests to rule out other medical problems that coincide with
gonadal dysgenesis 30% of the time. If any part of a Y chromosome is present in the karyotype, the
gonads should be removed because of the risk of gonadal malignancy.
• Low or low-normal FSH (hypogonadotropic hypogonadism) can be seen in cases of constitutional
delay, severe stress, or hypothalamic or pituitary dysfunction. Thyroid function tests, IGF-1 (a
reflection of growth hormone production), and prolactin should be assessed. In cases of low FSH,
MRI with IV contrast should be performed to evaluate for hypothalamic or pituitary masses (Fig. 22-1).
10. What are the hypothalamic causes of amenorrhea?
• Dysfunctional gonadotropin-releasing hormone (GnRH) secretion: can occur with polycystic
ovarian syndrome, excessive exercise, eating disorders, and malnutrition
• Isolated gonadotropin deficiency: can be caused by Kallmann syndrome (lack of GnRH neurons,
associated with anosmia) or be idiopathic
• Infection: tuberculosis, encephalitis or meningitis, syphilis, or sarcoidosis
• Neoplasms: craniopharyngioma, Langerhans cell histiocytosis, other tumors
11. What are pituitary causes of amenorrhea?
• Cell damage leading to deficient luteinizing hormone and FSH secretion: can occur with
autoimmune disease, thrombosis, or hemorrhage (Sheehan syndrome, see Chapter 68)
• Neoplasms: most commonly prolactinoma, but also inactive adenomas or other hormone-secreting
pituitary tumors including growth hormone leading to acromegaly and adrenocorticotropic hor-
mone, with resulting Cushing syndrome
KEY POINTS: PRIMARY AMENORRHEA
1. Primary amenorrhea is classically defined as the absence of menses by age 13 years with
no secondary sexual characteristics or by age 15 years with evidence of secondary sexual
development.
2. Gonadal dysgenesis (e.g., Turner syndrome) and müllerian agenesis are the most common causes of
primary amenorrhea.
3. Patients with müllerian agenesis and androgen insensitivity present with breast development but no
uterus. These conditions can be differentiated with a karyotype or testosterone level.
4. Initial laboratory workup of amenorrhea should include FSH, TSH, and prolactin determinations.
5. Patients with primary amenorrhea and hypergonadotropic hypogonadism (elevated FSH) should
have a karyotype performed.
6. Patients with primary amenorrhea and hypogonadotropic hypogonadism should have an MRI scan of
the brain with IV contrast performed.
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Figure 22-1. Workup of primary amenorrhea. CNS, Central nervous system; FSH, follicle-stimulating hormone.
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REPRODUCTIVE ENDOCRINOLOGY
12. What are the causes of primary ovarian insufficiency (POI)?
POI is defined as ovarian failure before the age of 40 years. It is also referred to as premature ovarian
failure. It has several causes:
• Genetic defects, including Turner syndrome and fragile X syndrome. If any XY cells are pres-
ent on karyotype, the gonads should be removed immediately to decrease the risk of germ cell
malignancy.
• Toxins can include chemotherapy, radiation, and certain viruses.
• Autoimmune disease: This can also cause thyroiditis, diabetes, and primary adrenal insufficiency
(Addison disease).
• Metabolic disorders: These disorders include galactosemia.
• Up to 80% of the time, POI is idiopathic.
13. When should a karyotype be ordered in a patient with amenorrhea?
• Patients with primary amenorrhea who have breasts but no uterus (differentiates between andro-
gen insensitivity and müllerian agenesis)
• Patients with primary amenorrhea and gonadal failure, to diagnose Turner syndrome or Swyer
syndrome (XY gonadal dysgenesis)
• Patients with secondary amenorrhea who have POI or signs of Turner syndrome (e.g., short stature,
webbed neck, high arched palate, shield chest)
14. What medications can cause amenorrhea?
• Medications that stimulate prolactin secretion: Prolactin has an inhibitory effect on GnRH secretion.
• Dopamine antagonists: Dopamine is a negative feedback inhibitor of prolactin release, so these
medications lead to increased prolactin secretion. Antidepressants, (e.g., tricyclics), antipsychot-
ics (e.g., risperidone and haloperidol), and some antiemetics (e.g., metoclopramide) are in this
category.
• Selective serotonin reuptake inhibitors (SSRIs) and monoamine oxidase inhibitors (MAOIs) can
induce amenorrhea through hyperprolactinemia. Other medications with this property include
histamine receptor antagonists (H
2
-blockers), reserpine, methyldopa, opiates, benzodiazepines,
barbiturates, estrogens, and antiandrogens.
15. What causes athletic amenorrhea, and should it be treated?
In athletes, amenorrhea can result from high physiologic stress levels, energy deficit, or abnormal
eating habits. Physiologic stress can increase catechol estrogens and β-endorphins and cause the
hypothalamus to decrease the pulse frequency of GnRH release. Over time, the hypogonadotropic
hypogonadism that ensues can lead to osteoporosis and stress fractures. The combination of
disordered eating, amenorrhea, and osteoporosis is referred to as the female athlete triad. Athletic
amenorrhea should be treated; patients should be encouraged to improve their diet, decrease stress
levels, and decrease the amount of strenuous exercise if possible. Estrogen and progesterone should
be replaced (oral contraceptives are a good option) if lifestyle changes are not effective.
16. What rare enzyme defects can cause amenorrhea?
Congenital adrenal hyperplasia (CAH) is an autosomal recessive disorder that can be caused by a vari-
ety of enzyme defects involved in steroidogenesis. Symptoms result from excessive or deficient pro-
duction of mineralocorticoids, androgens, and estrogens. The most common enzyme deficiency in CAH
is that of 21-hydroxylase. Girls with classic CAH caused by 21-hydroxylase deficiency have ambigu-
ous genitalia at birth as a result of exposure to androgens in utero, as well as salt wasting (hypona-
tremia and hypovolemia) from decreased mineralocorticoids. The nonclassic form of 21-hydroxylase
deficiency, however, may manifest in adolescents or young adults with oligomenorrhea or amenorrhea
and hirsutism. 17-Hydroxyprogesterone is elevated in patients with 21-hydroxylase deficiency.
Another enzyme deficiency in CAH is that of 17α-hydroxylase, which causes a lack of sex
steroid and cortisol production and elevated mineralocorticoids. Girls with this defect have normally
developed external genitalia but experience delayed puberty and primary amenorrhea because of a
lack of estrogen production. Excess mineralocorticoids can also lead to hypertension, hypernatremia,
and hypokalemia. These patients require exogenous estrogen and progesterone to attain sexual
maturity and prevent osteoporosis.
Other enzyme defects include defects of 11β-hydroxylase and 3β-hydroxysteroid
dehydrogenase.
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B
iBliography
1. Herman-Giddens ME, Slora EJ, Wasserman RC, et al. Secondary sexual characteristics and menses in young girls seen
in office practice: a study from the Pediatric Research in Office Settings network. Pediatrics. 1997;99:505–512.
2. Current evaluation of amenorrhea. ASRM educational bulletin. Fertil Steril. 2008;90:S219–S225.
3. Lentz GM, Lobo RA, Gershenson DM, Katz VL, eds. Comprehensive Gynecology. 6th ed. Philadelphia: Mosby; 2012.
4. Fritz MA, Speroff L, eds. Clinical Gynecologic Endocrinology and Infertility. 8th ed. Philadelphia: Lippincott Williams &
Wilkins; 2011.
KEY POINTS: SECONDARY AMENORRHEA
1. The most common cause of secondary amenorrhea is pregnancy.
2. Hypothalamic and pituitary causes of secondary amenorrhea include idiopathic conditions, eating
disorders or excessive exercise, infection, and neoplasms (most commonly prolactinoma).
3. POI is usually idiopathic but can also result from Turner syndrome, fragile X syndrome, metabolic
and autoimmune disorders, or chemotherapy or radiation therapy.
4. Medications that stimulate prolactin secretion include antipsychotics, antidepressants, gastrointestinal
medications, antihypertensives, and hormones.
5. Nonclassic CAH caused by 21-hydroxylase deficiency can cause secondary amenorrhea and hirsutism.
17-Hydroxyprogesterone is elevated in these patients.
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1. What basic information should you provide a couple who has stopped using
contraception and desires pregnancy?
Explain that the natural fecundity rate (chance per cycle of achieving pregnancy) is approximately
25% in young couples and decreases with age. Provide information about the proper timing of
intercourse around ovulation. Discuss when a further workup is necessary (irregular cycles, history
of pelvic infections, unable to conceive after 6 to 12 months of trying). Discuss the importance of
avoiding smoking and limiting caffeine intake, both of which may decrease fertility. Recommend
preconception use of folic acid (e.g., prenatal vitamins) to minimize neural tube defects.
2. A couple has sought your opinion concerning infertility versus sterility. What do
you tell them when asked about the chances of becoming pregnant?
With a fecundity rate of 25% in normally fertile couples, approximately 85% to 90% of couples will
conceive within 1 year with regular, unprotected intercourse. Infertility is the inability to conceive after
1 year of regular intercourse without contraception in women younger than 35 years of age or after
6 months of regular intercourse without contraception in women 35 years old and older. This problem
affects 10% to 15% of couples of reproductive age (i.e., 15 to 44 years old). Primary infertility applies
to patients who have never conceived, whereas secondary infertility is the term reserved for patients
who have previously conceived (including live born, ectopic, or abortion) and are currently infertile.
Sterility implies an intrinsic inability to achieve pregnancy, whereas infertility implies a decrease
in the ability to conceive. Sterility affects 1% to 2% of couples.
3. Is fecundity related to age?
Yes. An inverse relationship exists between fecundity and the age of a woman. This is caused by a
decrease in egg quality with age, likely as a result of deficient reproductive “machinery” within the
egg, that leads to an increase in the proportion of aneuploid embryos created. In addition, the number
of oocytes within the ovary declines because of progressive follicular atresia (by apoptosis). Fertility
starts to decline in the mid-30s, with an increase in this decline in the upper-30s and a much more
rapid decrease after age 40 years. In general, natural fertility is unlikely after age 43 to 44 years for
most women.
Sperm quality deteriorates somewhat as men grow older; the effect is slight, however, and
generally does not become a problem before 60 years of age. Men can also have a decrease in
testosterone production and subsequent reductions in sperm concentrations, motility (movement), and
morphology (shape).
4. What are three important goals that a generalist obstetrician-gynecologist should
achieve in working with an infertile couple?
1. Patient education: A couple needs to know the basics of human reproduction, the chances of
becoming pregnant, when it is best to have intercourse, common causes of infertility, investigative
tests available, the cost and discomfort associated with tests, and the therapies available—along
with their expected success rates.
2. Basic evaluation: Essential elements include documentation of ovulation and tubal patency and
testing for male factor problems. Peritoneal factors (adhesions and endometriosis) can also play
a role, but weighing the costs of investigation and treatment against the potential benefit may be
best left to a fertility specialist.
3. Emotional support and guidance: The clinician should counsel the couple on how far to go with
tests and when referral for further testing and treatment is appropriate.
5. What are the general causes of infertility, and how common are they?
• Pelvic factors (tubal disease or endometriosis): 35%
• Male factors: 35%
• Ovulatory dysfunction: 15%
CHAPTER 23
INFERTILITY
Lauren W. Sundheimer, MD, and Travis W. McCoy, MD
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