Download Sex Hormones In Females And Related Disorders

Sex Hormones In Females And Related Disorders
(see previous newsletter article for males)
Follicular Phase
Sex Hormone production
and measurement in
females
Ovulation
Follicle Stimulating Hormone
(FSH) Luteinizing Hormone
(LH), Oestradiol and
Progesterone
The hypothalamus produces
gonadotropin-releasing hormone
(GnRH) which stimulates anterior
pituitary production of FSH and
LH; FSH stimulates ovarian follicle
development and oestrogen
production during the follicular
phase; the midcycle peak of LH
stimulates ovulation (ovulation occurs
about 24 hours after peak LH) and
thereafter LH stimulates progesterone
production in the luteal phase by the
corpus luteum (see Figure 1 opposite).
This complex and varying hormone
pattern can make interpretation
difficult for the occasional requester.
In particular, specimens taken around
midcycle may be problematic as
the normal rise in LH (and resulting
increased LH/FSH ratio) may
be misdiagnosed as Polycystic
Ovary Syndrome (PCOS) and if, as
occasionally happens at midcycle,
FSH and LH both rise similarly,
menopause or ovarian failure may be
misdiagnosed (for typical follicular,
midcycle and luteal patterns see
tables opposite).
Timing of specimen: For the
above reasons a day 2-4 specimen is
best for assessing the sex hormones
for most purposes unless proof of
ovulation is required. In this case a
day 21 (assuming a 28 day cycle)
progesterone of greater than 20
nmol/L confirms ovulation. If cycle
length is usually longer or shorter
than 28 days, take the sample 7 days
before the usual end of the cycle. This
is because the luteal phase generally
takes 14 days regardless of overall
cycle length.
Luteal Phase
P
Endocrine
Cycle
E2
LH
FSH
Ovarian
Histology
Follicular
recruitment
Corpus
luteum
Dominant follicle
Menses
Endometrial
Histology
37.0
Body
Temp. 36.5
ºC
36.0
0
2
4
6
8
10
12
14 16
Days
18
20
22
24
26
28
Figure 1. Monthly Ovarian Cycle
Typical Follicular Pattern
FSH 4 U/L
(1-10)
LH 2 U/L (2-7)
Oest 255 pmol/L (77-920)
Prog 0.5 nmol/L (<1.0)
Typical Midcycle Pattern
FSH 11 U/L
(6-17)
LH 42 U/L
(9-74)
Oest 832 pmol/L (139-2380)
Prog 1 nmol/L
(<1.0)
Typical Luteal Pattern
FSH 3 U/L
(1-9)
LH 3 U/L
(1-9)
Oest 450 pmol/L
(77-1145)
Prog 25 nmol/L
(3.8-50.0)
Early morning specimens have
higher androgen (due to adrenal
diurnal rhythm) and prolactin levels
than afternoon specimens. Prolactin
levels are also higher during midcycle.
Useful hints:
• Remember to request a sex
hormone binding globulin (SHBG)
level if testosterone is measured
(most testosterone is bound to
SHBG and is thus inactive). This
enables the free testosterone or
free androgen index (FAI) to be
calculated; these are more useful
than testosterone alone.
• Hormones are measured using
immunological techniques and this
means that results using different
methods are not interchangeable.
Adapted from Harrisons Principles of Internal Medicine, 11th ed.
Sex Hormones In Females And Related Disorders continued
This is particularly important
with HCG levels when used to
diagnose or monitor tumours. Most
HCG assays used for pregnancy
assessment are not suitable for
tumour use as tumour-derived
HCG is often structurally different to
pregnancy-derived HCG; tumours
may be missed if the reason for
the test request is not clear on the
request form. Clinipath Pathology,
however, uses an HCG assay
(Roche) which has been certified
for both pregnancy and tumour
use.
Prolactin and
Galactorrhoea
Prolactin is produced by the
anterior pituitary; it rises during
pregnancy and functions by
stimulating milk production and
inhibiting LH and FSH secretion. This
inhibits ovulation and fertility which
is desirable during the perinatal
period and during breast-feeding.
After delivery prolactin elevations are
related to episodes of suckling.
Pathological elevation of
prolactin is the commonest
hypothalamic-pituitary endocrine
disorder and can cause
galactorrhoea, reduced libido,
amenorrhoea and infertility and will
ultimately result in osteoporosis if not
treated.
Mild to moderate prolactin
elevations (<2000 mIU/L) in the
non-pregnant/non-breast-feeding
patient are usually due to stress,
midcycle, medications (particularly
psychotropic medications eg
antipsychotics and antidepressants;
H2 antagonists eg cimetidine; calcium
channel blockers & oestrogens)
PCOS and breast stimulation and less
commonly due to hypothyroidism,
pituitary stalk damage, renal failure
and acromegaly.
With these moderate elevations
we advise a repeat sample taken a
week later after resting 20 minutes,
and if unexplained elevation persists,
prolactinoma should be excluded
by pituitary testing (TSH, T4, growth
hormone, IGF1, FSH, LH, oestradiol,
progesterone and 9am cortisol) and
pituitary imaging.
Psychiatric patients on
antipsychotics should have prolactin
checked routinely as chronic
elevations over 1000 mIU/L inhibit
ovulation, reduce oestrogen levels and
cause osteoporosis. Consideration
should be given to changing
medications if levels exceed 1000
mIU/L.
Elevations of over 2000 mIU/L
are usually due to microprolactinomas,
while elevations of greater than 5000
and typically around 10000 mIU/L are
seen in macroprolactinomas (tumours
>1cm), however, antipsychotic
medications and anti nausea drugs
(eg stemetil and domperidone) can
also occasionally cause elevations of
this order.
Macroprolactin is a confusingly
named condition which describes a
chronic elevation of prolactin due to
incidental binding to it by antibodies
in the patient’s circulation. These
antibodies prevent prolactin being
cleared; prolactin levels thus rise but
the hormone-antibody complex is
generally inactive. Macroprolactin is
thus usually considered an incidental
and not a pathological finding. At
Clinipath Pathology we routinely
exclude macroprolactin if the prolactin
level is over 1000 IU/L, or if it is
repeatedly elevated to a lesser extent.
Galactorrhoea is considered
abnormal if it persists more
than 6 months after delivery or
discontinuation of breast-feeding.
Clinipath Pathology Newsletter / Summer 2011
Bloody or non-milky discharges
are not considered to be true
galactorrhoea and local breast
pathology, including possible
breast cancer, should be excluded.
True galactorrhoea is usually
associated with elevated prolactin
(see above for causes) and fasting
morning specimens should be
checked for this. Those women
with galactorrhoea, normal menses
and normal prolactin probably have
increased sensitivity of the breast to
normal prolactin levels.
Investigation of
galactorrhoea:
Morning prolactin and IGF1
(rarely acromegally can present
with galactorrhoea and normal
prolactin) should be checked.
If prolactin is elevated, then
TSH, T4, U&Es, GH, IGF1,
cortisol, FSH LH oestradiol
and progesterone should be
measured.
Pituitary imaging may also be
required.
Puberty and its disorders
in girls
Normal Puberty: The normal
onset of puberty is between 8-13
years and the mean age of menarche
in Western populations is 12-13 years.
Puberty occurs because of rising
levels of sex hormones. FSH and
oestradiol levels may be fairly high in
the neonatal period (and may even
cause isolated breast development
in some infant girls) but are then
suppressed during childhood till the
onset of puberty.
Normal sequence and timing of
puberty: Breast development may be
the earliest manifestation of puberty
Sex Hormones In Females And Related Disorders continued
(precedes sex hair development in
60% of girls) and is due to conversion
of adrenal androgens to oestrogens.
Increased secretion of adrenal
steroids (adrenarche) especially
DHEA, results in increased sex hair
and apocrine sweat odour. Ovarian
maturation (gonadarche) normally
follows adrenarche. Menarche usually
follows 2-3 years after the onset of
breast development, and cycles are
usually irregular for about a year
varying between 21 to 45 days. Most
cycles are regular by 2-4 years post
menarche.
Initiation of puberty:
Puberty is triggered by initiation
of pulsatile release of GnRH from
the hypothalamic pulse generator
(approximately 10000 neurones
derived from the olfactory bulb) which
then stimulates FSH and LH release
and consequent ovarian development.
It is thought that increasing insulin
resistance in childhood initiates
pulsatile GnRH release; this view is
supported by the findings that obese
girls experience puberty sooner than
normals; that menarche occurs at a
critical body weight rather than age;
and that the age of menarche is now
younger than in previous generations.
Apart from the influence of body
weight, genetic factors account for
much of the variation in age of puberty
both in a familial and ethnic context
(eg African Americans enter puberty a
year before Caucasian girls).
Precocious puberty in girls:
This was defined (some 40 years
ago in the UK) as the development
of secondary sexual characteristics
before 8 years of age. The earlier
onset of puberty today has resulted
in recommendations that this be
reduced to less than 7 years in
Caucasians and less than 6 years in
African Americans.
Causes: Precocious puberty may
be GnRH mediated (ie accelerated
normal mechanism of puberty) or
GnRH independent (pseudopuberty).
GnRH mediated: Early maturation
of the GnRH mechanism occurs. FSH,
LH and oestradiol levels are elevated
for age.
• Most cases of precocious puberty
(85%) are due to idiopathic early
activation of GnRH pulsatile
secretion (commoner in girls than
boys) which results in early sexual
development, increased growth
rate and advanced bone age.
Treatment with GnRH agonists
down-regulates pituitary LH and
FSH secretion, slows progression
of puberty and thus can prevent
early menarche and closure of the
epiphyses and short adult stature.
is not due to early maturation of
the normal mechanism but to
other causes. Oestrogens and/or
androgens are elevated but LH and
FSH are suppressed. GnRH agonists
are thus ineffective and other drugs
e.g. oestrogen receptor blockers are
required if the primary cause cannot
be eliminated.
• Congenital adrenal hyperplasia:
excess adrenal androgens are
produced due to an enzyme
deficiency in the pathway to
cortisol synthesis. 21 hydroxylase
deficiency is commonest and 17
OH progesterone is thus elevated.
Presentation in girls is with
hirsutism and virilisation, which may
mimic precocious puberty.
• Oestrogen or androgen producing
tumours of ovary or adrenal
• PCOS may cause early puberty
by increasing insulin resistance as
outlined above.
• HCG producing tumours (HCG
stimulates ovarian oestrogen
production)
• Occasionally lesions of the
hypothalamus (tumours, infections,
inflammation) may trigger onset
of puberty by prematurely
triggering GnRH release from the
hypothalamic pulse generator.
• McCune Albright syndrome (due
to a G protein defect, LH and
FSH receptors in the ovary are
constitutively active and oestrogen
production is stimulated.)
GnRH independent
(pseudopuberty): In these cases,
excess sex hormone production
• Exogenous oestrogen and
androgen intake. (Foods,
medications, alternative
therapies).
Sex Hormones In Females And Related Disorders continued
Investigation of precocious
puberty:
U&Es, TFTs, FSH, LH, oestradiol,
testosterone, SHBG, DHEAS,
androstenedione,
17 OH progesterone.
Bone age should also be
checked. Imaging may be
required depending on findings.
Delayed puberty: This is defined
as the absence of breast development
by 13 years or the absence of
menarche by age 16 years.
Causes are either failure of the
hypothalamic/ pituitary initiation
mechanism (hypogonadotrophic) or
ovarian failure (hypergonadotrophic).
Hypogonadotrophic
hypogonadism: Low oestrogen,
gonadotrophins are normal or low.
Causes 1 & 2 are commonest, others
are rare.
• Constitutional: family history of
delayed puberty.
• Functional: Chronic diseases,
hypothyroidism, diabetes,
malnutrition, anorexia, excessive
exercise.
• Kallmans syndrome (failure of
development of hypothalamic
GnRH pulse generator; usually
with anosmia, more common in
males than females)
• Tumours/inflammatory lesions
of hypothalamus or pituitary
(craniopharyngioma, prolactinoma)
Hypergonadotrophic
hypogonadism: Low oestrogen,
elevated LH and FSH due to ovarian
dysgenesis or failure, or defects
of steroid hormone synthesis or
signalling in the pituitary/gonadal axis.
Turners syndrome is the commonest
cause.
• Turner Syndrome (streak ovaries,
XO, short stature, webbed neck)
• Other causes of gonadal
dysgenesis
• Autoimmune oophoritis
• Previous radiotherapy/
chemotherapy
• Defects in FSH and LH receptors or
sex steroid synthesis
• Complete androgen resistance
syndromes (patient is XY male but
phenotypically female, testosterone
levels are in the normal male range.)
those causing delayed puberty
(covered above) and in addition
include anatomical defects of the
genitourinary tract.
Secondary amenorrhoea: The
commonest cause is pregnancy!
Investigation of
Amenorrhoea:
Amenorrhoea lasting more than
3 months should be investigated
by U&Es, LFTs, FBC, TFTs,
HCG, prolactin, FSH, LH,
oestradiol, testosterone, SHBG,
androstenedione and DHEAS.
Investigation of delayed
puberty:
U&Es, LFTs, TFTs, LH, FSH,
oestradiol, testosterone, SHBG,
progesterone, karyotyping,
bone age.
Amenorrhoea, Menopause
and Premature ovarian
failure
Primary Amenorrhoea: (failure to
menstruate by 16 years).
The causes of primary
amenorrhoea are the same as
Clinipath Pathology Newsletter / Summer 2011
Hormone patterns in
amenorrhoea
• Patients with high oestradiol and
progesterone and suppressed LH
and FSH are usually pregnant. The
gonadotrophins are suppressed
because HCG is driving oestrogen
and progesterone synthesis which
in turn suppress FSH and LH.
Occasionally this pattern is difficult
to distinguish from atypical luteal
ovulatory profiles and an HCG
check is thus always advisable if
not already requested.
Sex Hormones In Females And Related Disorders continued
Pattern A: Typical Pregnancy
FSH
<1 U/L
LH
<1 U/L
Oestradiol
3540 pmol/L
Progesterone
95 nmol/L
• Patients with low oestradiol and
gonadotrophins have hypothalamic
amenorrhoea and causes such
as systemic illness, stress,
excess exercise, eating disorders,
hyperthyroidism, drugs of abuse,
pituitary/hypothalamic pathology
(especially prolactinoma) must
be excluded. This pattern is also
typical of oral contraceptive use.
Pattern B: Typical Hypothalamic
amenorrhoea
FSH
1 U/L
LH
1 U/L
Oestradiol
40 pmol/L
Progesterone
0.3 nmol/L
• Patients with reduced SHBG and or
increased androgens with/without
elevated LH/FSH ratios should be
assessed for PCOS.
Pattern C: Typical PCOS
Testosterone
2.1 nmol/L (0.3-1.7)
SHBG
12 nmol/L (26-110)
FAI
17.5 (0.3-5.6)
Free Testosterone 61 pmol/L (3-33)
• Patients with low oestradiol and
elevated FSH are likely to have
ovarian failure as typically seen in
the menopause.
Pattern D: Typical Ovarian Failure
or menopause
FSH
35 U/L
LH
16 U/L
Oestradiol
95 pmol/L
A precursor of this pattern is a
normal or even high oestradiol with
elevated FSH (and sometimes lesser
LH elevation) that is common in the
early stages of ovarian failure and
menopausal transition and reflects
decreasing ovarian responsiveness
to FSH. This last-described pattern
may be difficult to differentiate from
midcycle, however, at midcycle, LH
elevation is usually higher than FSH
elevation.
Pattern E:
Typical Early Ovarian Failure
FSH
23 U/L
LH
12 U/L
Oestradiol
1423 pmol/L
Menopause is defined as the
time of the cessation of menses and
in Western populations now occurs
at a mean of 51-52 years. Age of
menopause is largely genetically
determined. Multiparity increases and
lower socio-economic status and
smoking reduce this age.
Premature ovarian failure (POF)
is said to occur if onset of failure is
before 40 years age and may affect
up to 1% of women.
Premature ovarian failure may
be idiopathic or secondary to ovarian
insults (radiotherapy, chemotherapy
and possibly mumps) or to the
inherited auto-immune polyglandular
syndrome which is associated with
ovarian and adrenal antibodies and
failure of other endocrine systems.
A GTT, calcium, TFTs, and 9am
cortisol should thus be checked
together with ovarian and adrenal
antibodies. Note that onset of ovarian
failure is frequently relapsing and
occasional women may conceive
spontaneously after the onset of
POF.
Androgens, hirsutism,
virilisation and PCOS
Female androgen production:
Most serum testosterone is bound
to SHBG and is inactive, thus it is
essential to measure SHBG as well
as testosterone to try and estimate
the free, active fraction (FAI and
calculated free testosterone). In
normal adult women, about half of
testosterone production is ovarian
and the remainder adrenal. Ovarian
testosterone production decreases at
menopause but SHBG also falls due
to low oestrogens and the net effect
is an increase in the relative amount
of free testosterone which may cause
hirsutism after menopause. Other
androgens are DHEAS (mainly adrenal
origin) and androstenedione (adrenal
and ovarian origin).
Clinical setting: About 10% of
women are hirsute (ie. have male
pattern hair growth) and most of these
are familial/idiopathic or ethnic (darker
individuals and Mediterranean origin).
Patients with virilisation have
in addition acne, male habitus,
male pattern balding, deep voice,
clitoromegally, etc. Virilisation (unlike
hirsutism alone) is usually due to
significant pathology. Sudden onset
of hirsutism and virilisation is almost
always due to androgen secreting
tumours. Very high androgen levels
are also suggestive of tumour
production.
Causes of hirsutism and
virilisation:
• PCOS (by far the most common
cause)
• Congenital Adrenal Hyperplasia
(mild form of 21 hydroxylase
deficiency; patients have elevated
17 OH progesterone)
• Cushings
Sex Hormones In Females And Related Disorders continued
• Androgen-secreting tumours of
ovary or adrenal
• Partial form of Testicular
Feminisation (XY male with partial
androgen resistance e.g. 800 metre
gold medallist Caster Semenya)
• Exogenous androgens
Investigations of hirsutism
and virilisation:
Prolactin, TFTs, Testosterone,
SHBG, DHEAS,
androstenedione and 17 OH
progesterone together with day
2-4 FSH, LH, oestradiol and
progesterone. 24 hour urinary
cortisol (or dexamethasone
suppression) should be
checked if Cushings is a clinical
possibility.
NOTE: Commercial testosterone
assays are not sensitive enough to
reliably measure testosterone levels at
or below the female lower reference
limit (ie at or below the female lower
normal limit) and should not be
relied upon to diagnose “androgen
deficiency” in women.
PCOS
These patients present with
hyperandrogenism, irregular
menstruation and infertility. They are
commonly overweight or obese and
have polycystic ovaries on ultrasound,
however polycystic ovaries are not
exclusive to PCOS.
Insulin resistance, dyslipidemia,
glucose intolerance and type 2
diabetes are strongly associated.
Incidence is up to 12% and rising
with increasing obesity; first degree
relatives are at increased risk.
Clinically PCOS commonly
develops during puberty; hirsutism is
the commonest finding followed by
menstrual irregularity or amenorrhoea
(20% of cases). Anovulation results in
infertility. Ultrasound shows polycystic
ovaries (>12 follicles per ovary) which
reflects failure of developing follicles
to ovulate. Polycystic ovaries may,
however, also be found in normal
women. Obesity is present in more
than 50% of cases of PCOS and is
typically centripetal (due to visceral
fat) with increased waist/hip ratio and
accompanying insulin resistance.
In these cases high insulin levels
correlate with low SHBG and thus free
testosterone levels increase.
Insulin resistance is also present in
non-obese PCOS; the mechanism is
uncertain. Patients with severe insulin
resistance may develop acanthosis
negricans. Glucose tolerance testing
is advisable for all PCOS patients
(fasting blood glucose may be
normal but 2 hour specimen is often
abnormal) as these patients are at
high risk of diabetes (approximately a
third develop type 2 diabetes by age
40 years). Patients are also at high risk
of dyslipidaemia (low HDL, high LDL
and triglycerides), metabolic syndrome
and cardiovascular disease.
Pathogenesis and Treatment
of PCOS
Increased androgens and insulin
resistance (present in obese and
Clinipath Pathology Newsletter / Summer 2011
non-obese PCOS) are probably both
involved. Insulin resistance results in
reduced SHBG and thus higher free
testosterone levels. Ovarian androgen
production is also increased due to
high LH levels. Increased androgens
cause android fat deposition, which
worsens insulin resistance and
dyslipidaemia.
Treatment is by OCP (suppresses
ovarian androgen production and
increases SHBG levels, thus reducing
free androgen levels) anti-androgens
e.g. spironolactone, flutamide and
finasteride, and insulin sensitization by
weight loss, exercise and metformin.
Hormone profile in PCOS
Low SHBG, mild to moderate
elevation of FAI/free testosterone
and mild elevation of testosterone
(usually less than 3 nmol/L) are the
most reliable biochemical markers,
especially in obese patients. (see
pattern C)
Lean patients with PCOS generally
have elevated LH/FSH ratios >2;
these ratios may, however, be normal
in obese patients and false positives
are seen if testing is done near to
midcycle.
Testosterone levels > 6nmol/L
and DHEAS >20umol/L are
suggestive of tumour rather than
PCOS production.