Archives of Perinatal Medicine 18(1), 27-36, 2012 REVIEW PAPER PCOS and metformin: from pharmacology to clinical use for women’s health ALESSANDRO D. GENAZZANI1, FEDERICA RICCHIERI1, ALESSIA PRATI1, ELISA CHIERCHIA1, ERIKA RATTIGHIERI1, GIOVANNA BOSCO1, GIULIA DESPINI1, ANNALISA CAMPEDELLI1, ALBERTO FARINETTI2, SUSANNA SANTAGNI1 Abstract Metformin is an old compound optimal for treatment of type 2 diabetes. Since when PCOS patients have been
reported to have insulin resistance, metformin has been demonstrated to modulate several aspects of PCOS and
to improve the most common cause of menstrual irregularity, inesthetisms and infertility. Metformin induces
a better control of glucose uptake inducing a lower synthesis/secretion of insulin. Such effect permits to reduce
insulin resistance which is the cause of the compensatory hyperinsulinemia typical in most but not all of PCOS
patients. The positive control of metabolism has many positive effects on the hormonal patterns such as the
restoration of menstrual cyclicity, ovulatory cycles and fertility since abnormal insulin levels affect the hypo-
pthalamus-pituitary-ovarian functionas well as peripheral tissues use of glucose. The combination of an improved
life-style with metformin treatment improves the impairments typically observed in hyperinsulinemic PCOS
patients, reducing the possible evolution towards to the metabolic syndrome and type 2 diabetes; and when
pregnancy occurs, it consistently reduces the risk of gestational diabetes, eclampsia and hypertension. Though
it might seem that metformin is the “optimal treatment” for PCOS patients, only hyperinsulinemic PCOS patients
are those with higher chances to get the best results from metformin administration, mainly if diet and life-style
are attentively combined. Key words: PCOS, metformin, hyperinsulinemia, chronic anovulation, obesity, BMI, insulin resistance Introduction
mia, thyroid diseases, androgen-secreting tumors and
Metformin is quite an old compound introduced into
adrenal dysfunction/hyperplasia) [4]. These criteria did
clinical use in 1957. From the chemical point of view is
not include the presence of polycystic ovaries at ultra-
1,1-dimethylbiguanide hydrochloride, a biguanide cur-
sound examination because it was observed that poly-
rently used as an oral antihyperglycemic agent for dia-
cystic ovaries could also be present in healthy eumenor-
betes mellitus. In these last 20 years, growing evidences
rheic women [5]. A few years later, during the Euro-
occurred to demonstrate that a large percentage of
pean Society of Human reproduction and Embryology
PCOS patients with or without obesity, show insulin re-
(ESHRE)/American Society for reproductive Medicine
sistance and a reactive compensatory hyperinsulinemia
(ASRM) conference, the diagnostic criteria were expand-
and that the use of metformin is optimal not only in the
ed and PCOS was considered as present when at least
presence of diabetes mellitus Type 2, but also in patients
two of three features were diagnosed: oligo or anovula-
with PCOS and hyperinsulinemia, resolving several
tion, clinical/ biochemical hyperandrogenism and poly-
issues such as menstrual cyclicity, fertility, hormonal
cystic ovaries as assessed by ultrasound examination [5].
levels and metabolic syndrome (MS) [1].
This evolution was relevant because it permitted theinclusion of women with PCOS who were excluded by
PCOS characteristics
previous NIH criteria [4]: those with polycystic ovaries
Polycystic ovary syndrome occurs in as many as
affected by hyperandrogenism and ovulatory cycles, or
8-10% of women of reproductive age [2], with onset ma-
chronic anovulation and normal androgen levels.
nifesting as early as puberty [3]. From the very begin-
More recently, the Androgen Excess and PCOS So-
ning, diagnostic criteria proposed by the NIH for PCOS
ciety indicated that PCOS should always be considered
were the presence of hyperandrogenism and chronic
an androgen excess disorder and concluded that PCOS
anovulation with clear exclusion of related ovulatory or
was, above all, a disorder of androgen biosynthesis, utili-
other androgen excess disorders (i.e., hyperprolactine-
1 Department of Obstetrics and Gynecology, Gynecological Endocrinology Center, University of Modena and Reggio Emilia2 Department of General Surgery, University of Modena and Reggio Emilia, Modena, Italy
A.D. Genazzani, F. Ricchieri, A. Prati et al.
Despite the diagnostic criteria, PCOS is still an un-
quent anovulatory cycles. All this results in a chronic
clear disease in terms of pathogenesis, and although the
hyperestrogenic state with the reversal of the estrone:
main clinical features related to the syndrome are men-
estradiol ratio that might predispose to endometrial pro-
strual irregularities, anovulation and clinical/biochemical
liferation and to a possible increased risk for endome-
signs of hyperandrogenism, PCOS patients frequently
show other physiopathological characteristics. Recently
Normally, less than 3% of testosterone circulates as
it has been made clear that both genetic and environ-
unbound in the serum. In fact, most circulating andro-
mental factors may contribute to the onset of PCOS fea-
gens are bound to SHBG, thus being biologically in-
tures [7, 8]. On such genetic predisposition, environmen-
active. Any condition that decreases the levels of SHBG
tal factors may play a key role, such as peculiar lifestyle,
or other binding proteins can lead to a relative excess of
types of food, living conditions and also the impact
free circulating androgens. In PCOS, hirsutism usually
during the intrauterine growth [8]. In fact, if intrauterine
occurs with decreased SHBG levels and obesity [13, 15].
growth is characterized by an exposure to exaggerated
A great percentage of PCOS patients show over-
androgen levels, this peculiar situation may lead to the
weight up to severe obesity, and typically any excess of
development of hyperandrogenism and ovarian dysfunc-
weight can induce a reduction of peripheral tissues sen-
sitivity to insulin, thus inducing the compensatory hyper-insulinism.
Endocrine profile of PCOS patients
It is relevant to say that hyperinsulinemia may be
Polycystic ovary syndrome is characterized by in-
central to the pathogenesis of the syndrome in many
creased ovarian and adrenal androgens, increased lutei-
cases, because it can induce higher ovarian androgen
nizing hormone (LH) levels, high estrogen levels (espe-
production and anovulation [16, 17], sustained also by
cially estrone) due to extraglandular conversion from
the abnormal LH secretion, with a higher frequency of
androgens, lower levels of sex hormone-binding globulin
menstrual abnormalities than in normoinsulinemic wo-
(SHBG) and higher levels of insulin, the latter often in
men with PCOS [18, 19]. Insulin resistance and compen-
satory hyperinsulinemia are metabolic disturbances easi-
Hyperandrogenism is a key feature of the syndrome,
ly observable in at least 45-65% of PCOS patients, and fre-
although it is not constant [9]. It is mainly of ovarian
quently appear to be related to excessive serine phos-
origin with an adrenal contribution, since a certain per-
phorylation of the insulin receptor [11, 20].
centage of PCOS patients might show a mild steroido-genetic defect in adrenal glands (such as for 21-hydro-
Metabolism & PCOS
xylase) or just a higher adrenal hyperactivation due to
In PCOS patients, there is an increased risk of
stress [10]. Androstenedione and testosterone are the
developing Type 2 diabetes and coronary heart disease
best markers of ovarian androgen secretion, while de-
(CHD) [21-23]. Such risk has also been demonstrated to
hydroepiandrosterone sulfate (DHEAS) is the best mar-
be higher in postmenopausal women, previously demon-
ker of adrenal secretion. Most testosterone is derived
strated to be PCOS during fertile life [24, 25]. PCOS has
from peripheral conversion of androstenedione and from
been reported to have an increased risk of MS, which
direct ovarian production. Dysregulation of cytochrome
refers to a clustering within the same individual of hy-
p450c17, the androgen-forming enzyme in both the
perinsulinemia, mild-to-severe glucose intolerance, dis-
adrenal glands and the ovaries, is the central pathogenic
lipidemia and hypertension, and an increased risk for
mechanism underlying hyperandrogenism in PCOS [11,
cardiovascular disease (CVD) and diabetes [26-28].
12]. In the presence of 5a-reductase, testosterone is
In 2006, the International Diabetes Federation de-
converted within the cell to the more potent androgen
fined the features of the MS, and defined central obesity
dihydrotestosterone. Excess or normal 5a-reductase ac-
as present when the waist circumference is above 80
tivity in the skin determines the presence or absence of
cm; in European women, this was considered as a ne-
hirsutism [13]. Additionally, estrone plasma levels,
cessary prerequisite risk factor for the diagnosis of MS
a weak estrogen with biological activity 100-times less
[29]. However, it is of great relevance to point out that
than estradiol, are increased as a result of peripheral
although the MS has been identified for more than 80
conversion of androstenedione by aromatase activity –
years, only in these last years has controversy about its
more active in PCOS than in healthy controls – while
estradiol levels are normal or low because of the fre-
PCOS and metformin: from pharmacology to clinical use for women’s health
recruitment and maturation [7, 43, 44]. 45-65% of PCOS
patients show insulin resistance and the compensatory
• Elevated triglycerides ($ 1.7 mmol/l),
hyperinsulinemia [7, 45], and this percentage is signifi-
• Reduced HDL (< 1.29 mmol/l in women),
cantly higher than age- and BMI-matched healthy con-
• Specific treatment for lipid abnormalities,
trols [46]. Obviously, when insulin resistance is present
• Elevated blood pressure (systolic $ 130 mm Hg or
independently from obesity, whatever the weight gain
that might occur, it certainly exaggerates insulin resis-
• Specific treatment or precedent diagnosis of hyper-
tance and more severely alters the glucose metabolism
• Fasting plasma glucose at least 5.6 mmol/l,
It is important to remember that several studies
• Previous diagnosis of Type 2 diabetes mellitus.
reported that insulin modulates LH secretion from
The prevalence of MS in polycystic women is appro-
pituitary cells in vitro [40] and in vivo, and that the re-
ximately 40-45% [30], and the main predictor factors are
duction of hyperinsulinemia induces the significant
the elevated free serum testosterone and reduced serum
decrease of LH plasma levels [38, 47, 48], although it is
SHBG level [31]. The association of MS with PCOS
not clear whether decreased LH levels are due to the
appears to be particularly strong in those PCOS women
reduced insulin levels or secondary to the recovery of
who are young (< 30 years) and overweight or obese
ovarian function (i.e., estrogen production) induced by
Women with PCOS have lower HDL levels, higher
Excess insulin increases androgen concentrations
LDL:HDL ratios and higher triglyceride levels than
blocking follicular maturation and increasing cytochrome
healthy eumenorrheic women [22]. All these are induc-
P450c17a activity, a key enzyme in the synthesis of both
tors of subclinical atherosclerosis as demonstrated by
ovarian and adrenal androgens [7, 40]. This situation
the increased thickness of the carotid intima media and
typically increases 17-hydroxyprogesterone (17OHP),
by the higher endothelial dysfunction observed in PCOS
androstenedione and testosterone plasma levels. The
patients [33, 34], probably related to the insulin resis-
excess of intraovarian androgens negatively modulates
tance and/or to the higher free testosterone plasma level
follicular function and ovarian activity, thus inducing the
typical stromal hypertrophy and maintaining ovarian
Indeed, several studies reported an increased risk
factor profile for cardiovascular disease in women with
When abnormal insulin sensitivity is diagnosed, the
PCOS [37]. It is of great relevance the fact that women
use of metformin might be suggested [7, 50]. Metformin
with PCOS have an increased risk for impaired glucose
reduces hepatic glucose production from 9 to 30% and
tolerance and Type 2 diabetes mellitus [38, 39], with
on peripheral tissues, such as muscle cells and adipo-
a tendency to an early development of glucose intolerance
cytes, metformin acts by increasing glucose uptake
state [40, 41]. In fact, the decrease of insulin sensitivity in
PCOS women appears to be quite similar to that ob-
Patients with PCOS are insulin resistant and this
served in patients with Type 2 diabetes mellitus and to
condition typical y decreases insulin’s ability to stimulate
be relatively independent from obesity, fat distribution
glucose disposal into peripheral cells and decreases the
and lean body mass [42]. On the other hand, there is
glucose response (i.e., glucose uptake by the cells) to
strong evidence that obesity, particularly the abdominal
insulin [7]. In addition, metformin positively acts on
phenotype, represents an important independent risk
hormonal PCOS abnormalities through a direct and/or
factor for glucose intolerance in PCOS women [39].
indirect action on steroidogenesis [7]. In fact, the reco-very of normal ovulatory function is probably due to thedirect modulation of metformin on the ovarian tissues
Rationale of metformin use in PCOS women
and to the metformin-induced normalization of the ova-
The logic for the use of insulin sensitizer drugs,
rian steroidogenesis (lowering androgen production),
such as metformin, to treat patients with PCOS is the
thus determining the normal feedback on pituitary,
fact that a large percentage of PCOS patients have been
lowering LH secretion and LH pulse characteristics
demonstrated to have insulin resistance and a compen-
[47, 48]. Metformin improves steroidogenesis not only
satory hyperinsulinemia that negatively affect ovarian
at the ovarian, but also at the adrenal level, since insulin
function in terms of steroid biosynthesis and follicular
plays specific modulatory roles on these two distinct
A.D. Genazzani, F. Ricchieri, A. Prati et al.
endocrine glands that have the same enzymatic path-
increased, slowly, up to the most effective dosage for the
ways [51, 52]. In fact, it has been demonstrated that
patient, as reported by Nestler [58, 59].
metformin administration ameliorates adrenal enzyme
The known side-effects, although very limited in
incidence, are abdominal discomfort, constipation, diar-
A recent meta-analysis of the published studies de-
rhea, flatulence, heartburn, indigestion, nausea and
monstrated that the use of insulin sensitizers do not re-
vomiting [7, 60]. It is relevant the fact that the patient
duce hyperandrogenism better than oral contraceptives
needs to help metformin modulation(s) on the metabolic
[54], but as recently reported, the typology of PCOS to
side following all the advices concerning feeding and
be treated is of great relevance, since only when insulin
weight control. The experience suggests that metformin
sensitivity is abnormal metformin shows a greater effi-
positively affects the metabolic problems of hyperinsu-
cacy on all the PCOS features, including hyperandro-
linemic, overweight/obese women together with a low
genism [48]. Obviously, it cannot be excluded that other
caloric diet and a minimum of physical activity. Since
metabolically active hormones (e.g., leptin, resistin,
metformin modulates insulin sensitivity, it works per-
adiponectin and gherelin) are positively activated by met-
fectly to restore insulin sensitivity within the normal
formin administration and thus participate in the im-
ranges, and this usually happens when physical activity
provement of the reproductive function at the hypo-
and loss of weight also induce the reduction of peri-
thalamus-pituitary-ovarian level [55]. However we have
pheral tissue insulin resistance together with metformin
to remember that metformin effectiveness on repro-
action [82]. However, it should be noted that previous
ductive and on metabolic parameters is mainly exerted
data demonstrated that withdrawal of metformin treat-
in association with a reduction of circulating insulin
ment can be followed within 3 months by a reversal to-
levels, thus supporting the hypothesis that a high insulin
ward a pretreatment hyperinsulinemic state [57, 61, 62].
level is one of the main effectors/modulators of the cli-
Recent data suggest that metformin is more effective
nical and endocrine dysfunctions of PCOS [7, 56].
in insulin-resistant PCOS patients, with normal BMI,probably because some constitutional abnormality might
Metformin therapeutic regimens
be at the basis of the insulin resistance. Nevertheless,
The therapeutic dose of metformin cannot be stan-
overweight (but not necessarily obesity) remains a fea-
dardized. Since its main indication is to treat diabetes,
ture that represents a strong indicator of good results
most of the dosages have been set according to the
when coupled with insulin resistance [53, 47], since a
levels of glycemia achieved with the treatment, and the
recent report showed equal response to metformin in
amount of metformin administered may vary from 500 to
those who were lean and obese [63]. However, it is inte-
1500 mg or more per day [7]. On the contrary, an ex-
resting to point out that lifestyle changes have been
tremely variable dosage has been used to treat PCOS,
demonstrated to be more effective in preventing diabe-
but up to now, no dose-finding study is available for
tes risk and MS than treatment with metformin [64] and
PCOS, probably because there are various end points
that metformin suspension induced a certain percentage
and goals for PCOS patients to reach, such as the re-
of reversion of the beneficial effects on insulin sensitivity
covery of menstrual cyclicity and of ovulation, loss of
and on hyperandrogenism, and is probably related to the
weight, reduction of hirsutism and skin defects. It is,
simultaneous worsening of both the ovarian function and
however, important to point out that clinical studies
clearly demonstrated that after long-term metformin
In our opinion, the positive effects induced by met-
treatment, drug suspension induces a quick reversion of
formin administration can be maintained when treatment
the beneficial effects on peripheral insulin sensitivity [7,
is prolonged over the time (up to 12 months or more) and
57]. In addition, because recent data showed that better
it is combined with a controlled diet and with moderate
clinical results were obtained in insulin-resistant rather
physical activity to aid metabolism and weight loss,
than in non-insulin-resistant PCOS patients [48], a clear
especially when overweight or obesity is present [1, 65].
adjustment of the dose of metformin must be performedaccording to the BMI and insulin resistance. The
When is metformin usefull?
treatment must be started with a low dose, administered
Metformin shows beneficial effects according to the
few minutes before lunch and dinner (10-15 min before),
clinical characteristics of the patient, and the more of
because an empty stomach minimizes the possible drug-
these features present at the same time, the higher the
related side affects [7], and only after 3-7 days can it be
chance of metformin treatment being effective [86].
PCOS and metformin: from pharmacology to clinical use for women’s health
weight or obesity as well as of compensatory hyperinsuli-
Body weight, evaluated as BMI, is a fundamental
nemia. However, this cannot be extended to all PCOS
characteristic. The higher the BMI is the higher the
patients. Recent data clearly reported that there are
amount of fat is present triggering a compensatory hy-
several kinds of genetic situations that are the genetic
perinsulinism. Unfortunately, this is not a general rule;
causal triggers or might just be the starting triggers if
it is valid for overweight or obese patients only. In fact,
combined with predisponent environmental factors
several studies reported that a certain percentage of
[7, 8]. It is important to observe that ethnic background
PCOS patients as well as a certain percentage of the
is probably relevant as these genetic factors, since PCOS
normal population have constitutional insulin resistance
and/or mild-to-severe hyperandrogenism are more fre-
concomitantly with a lean body mass [7, 66, 67], and
quent in some populations than in others, as well as the
when patients were treated independently from the
incidence of metabolic diseases (i.e., diabetes Type 2),
BMI, all of them demonstrated a beneficial effect in in-
quite often mirroring a greater use of carbohydrates in
sulin plasma levels, insulin sensitivity and in AUC for
insulin under the OGTT [66]. Our data demonstrateda great efficacy of metformin administration in non-obese
What metformin can ameliorate
PCOS patients, mainly in those with abnormal insulin
From the clinical point of view it cannot be stated
response to OGTT and/or fasting hyperinsulinism [48].
that metformin is the treatment for PCOS patients, but
These data let us infer that the ability to be sensitive to
it is rather important to underline that metformin can be
insulin is probably a real constitutional aspect; every
of great relevance when two or more of the aforemen-
patient has their own and it is worsened when BMI in-
tioned possible predictors are present [7]. Let’s see
Insulin sensitivity/resistance Effects on menstruation
This is the most important feature. Metformin has
80% of PCOS have oligomenorrhea or amenorrhea
more indications for PCOS patients with high basal
and oligoovulation or anovulation [69, 70]. Metformin
insulin levels and/or with abnormal response to the
administration was reported to restore normal menstrual
OGTT [48], independently from BMI. Only insulin-re-
cyclicity in a high percentage of the patients affected by
sistant individuals may benefit from metformin admini-
oligomenorrhea or amenorrhea [53, 71, 72], but was less
stration in terms of both insulin sensitivity and of insulin-
effective than oral contraceptives [73, 74] since ita acts
induced metabolic and hormonal functions [7, 48].
through a specific effect on metabolism and on the re-duction of hyperinsulinemia. Androgen excess Effects on fertility
In general, hyperandrogenism is a common feature
The fact that metformin improves metabolism, re-
of PCOS patients and cannot be considered a predictor
solves hyperinsulinemia and all hormonal impairments
of metformin efficacy. However, since hyperinsulinism
induced by this latter, explains how it might be possible
might be a relevent trigger of anovulation and oligome-
a specific effect of metformin on fertility. Recent reviews
norrhea, it can be argued that the combination of men-
and data clearly reported that metformin is not better
strual irregularities, hyperandrogenism and anovulation
than clomiphene citrate (CC) to induce ovulation [61,
can be positively affected by metformin administration.
75-77], but it is fundamental to remember that these two
compounds are affecting the hormonal profiles in com-
Waist-to-hip ratio
pletely different ways! It is important to remember that
The presence of overweight or obesity is certainly
metformin and CC have completely different mecha-
a risk factor for CVD in PCOS patients, and it is of great
nisms of action, and metformin may act on the repro-
importance to state that a high waist-to-hip ratio (> 0.8)
ductive axis as a secondary hormonal effect, mainly rela-
specifically indicates a greater amount of fat at the abdo-
ted to the improved (i.e., lowered) insulin plasma levels
minal level, which is the typical android distribution [68].
and insulin resistance [7, 58, 59]. In fact, while met-formin acts on insulin pathways, CC acts directly on the
Genetic factors
reproductive axis. Clinical data suggested that hyper-
For sure, environmental factors (such as lifestyle
insulinemia and insulin resistance could be responsible
and feeding) deeply condition the occurrence of over-
for the ovarian abnormal response occurring in OHSS
A.D. Genazzani, F. Ricchieri, A. Prati et al.
[78]. Although no clear evidence has been provided,
stration that both hyperandrogenism and impaired peri-
hyperinsulinemic PCOS patients undergoing metformin
pheral insulin sensitivity may increase the risk of CVD
administration before and/or during ovarian stimulation
[84, 85], although prospective controlled data on CVD
for the search of spontaneous pregnancy or IVF might
morbidity and mortality in PCOS patients has never
Effects on hyperandrogenism Effects on pregnancy & on risk of miscarriage
Improvement of ovarian function under metformin
Patients with PCOS are likely to develop gestational
treatment determines a relative improvement of hyper-
diabetes in 30-40% of cases [86, 87], with a higher chan-
androgenism and its clinical signs, such as acne and
ce than normal pregnant women [88]. Various data also
hirsutism. In general, hyperandrogenism and its signs
demonstrated that metformin use during pregnancy
are reduced by metformin administration because it
reduced the risk of gestational diabetes through the
reduces ovarian androgen production, ovarian P450c17a
reduction of preconceptional BMI, fasting insulin levels
activity and free testosterone concentration [7], and
and insulin resistance [87, 89]. Various reports con-
within few months it also reduces the Ferriman–Gallway
firmed the efficacy of metformin treatment in PCOS
pregnant women reducing significantly the risks ofgestational diabetes [89-92] and of preeclampsia [93],
Effects on body weight
although others did not show beneficial effects on mis-
Metformin treatment and lifestyle intervention have
carriage risk [76]. Although such data are of extremely
been reported to be more effective in reducing body
great clinical relevance, not all of the reports studied
weight, BMI and visceral fat in obese subjects than
large populations or were a placebo-controlled study. In
lifestyle intervention alone [50, 65]. This means that
any case, a recent meta-analysis confirmed that there is
metformin cannot be considered a specific antiobesity
no difference in abortion risk in PCOS patients under-
drug because lifestyle changes and a balanced diet to-
going metformin treatment before pregnancy when
gether with physical activity are fundamental to metfor-
compared with normal population [94, 95]. However, the
min co-treatment and might improve the chances of
safety of metformin administration during pregnancy
success [79, 80]. However, it is of relevance to point out
was attently evaluated, and no congenital abnormalities
that metformin has been demonstrated to improve body
or adverse fetal outcomes were related to metformin
weight control in obese PCOS patients by acting both
[96, 97]. Moreover, no negative effects on growth, motor
directly on the CNS and indirectly via adiponectin modi-
and social development in infants were reported when
fication [81], but in general it has a marginal effect on
metformin was administered to PCOS women during the
weight loss as monotherapy, as recently reviewed by
Palomba et al., who stated that lifestyle modifications re-main the cornerstone for weight loss in obese PCOS
Effects on mood & quality of life
patients, although metformin cotreatment might impro-
Last but not least, one important aspect is the
quality of life. PCOS patients have been demonstrated toperceive life significantly worse than healthy controls or
Effects on the risk of Type 2 diabetes & CVD
other patients affected by other diseases [100]. In ge-
PCOS patients with insulin resistance have a higher
neral, women are nearly twice as likely to experience
risk for developing Type 2 diabetes [50, 80]. The preva-
major depressive disorders as men [101], but it is of
lences of insulin resistance and diabetes in PCOS pa-
great interest to report that several studies suggest qua-
tients, especially if they are obese, is approximately 30-
lity of life, body age concerns and sexual dissatisfaction
40% and 5-10%, respectively, and this is three- to seven-
in PCOS [100-103], as well as a high degree of occur-
fold greater than the normal population [82, 79]. Since
rence of depressive state [104]. Obesity, clinical signs of
the incidence of cardiovascular diseases is quite high in
hyperandrogenism (acne, hirsutism and alopecia) and
diabetics, it has to be seriously considered that PCOS
infertility seem to be the main elements on which such
patients might also be exposed to a higher risk of CVD
great psychosocial discomfort find basis [105, 106], and
and/or its precursors such as hypertension [83, 37],
when an adequate treatment improved all such features,
since they are at a higher risk for diabetes than the
quality of life and well-being improved again [107].
normal population. This fact is enforced by the demon-
Interestingly, such a positive effect was also observed
PCOS and metformin: from pharmacology to clinical use for women’s health
under metformin administration. Indeed, a significant
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J Thromb ThrombolysisDOI 10.1007/s11239-006-9046-zThrombin generation in mesalazine refractory ulcerative colitisand the influence of low molecular weight heparinAnton A. Vrij Æ Ardi Oberndorff-Klein-Woolthuis Æ Gerard Dijkstra ÆAndrea E. de Jong Æ Rob Wagenvoord Æ Hendrik C. Hemker ÆReinhold W. Stockbru¨ggerÓ Springer Science+Business Media, LLC 2007differences were observed on the cl
Informed Consent for Oral Conscious Sedation The following is provided to inform patient, or the parent/guardian of a patient under the age of 18 years, of the choices and risks involved with having treatment under conscious sedation. This information is presented to enable them to be better informed concerning their treatment. The type of sedation administered will be determined on an in