Polycystic ovary syndrome (PCOS)
Adam H Balen
MD DSc FRCOG
Leeds Centre for Reproductive Medicine, Leeds Teaching Hospitals, Leeds, LS14 6UH, UK
*Correspondence: Adam H Balen. Email: email@example.com
Accepted on 25 July 2016. Published Online 21 January 2017.
The symptoms of polycystic ovary syndrome (PCOS) include
menstrual cycle disturbance and features of hyperandrogenism
(hirsutism, acne and alopecia), with associated fertility problems,
obesity and psychological issues.
There are ethnic variations in expression of PCOS related to
differences in insulin metabolism and this may impact upon
Obesity has a major impact on the expression of PCOS and the
efﬁcacy of the management of all aspects of the syndrome, in
The management of anovulatory infertility involves lifestyle
modiﬁcation and therapies to induce ovulation, namely clomifene
citrate, gonadotrophin therapy and laparoscopic
For those who do not wish to conceive the management of
menstrual problems requires prevention of endometrial
hyperplasia and adenocarcinoma and consideration of the long
term metabolic risks.
To understand the full spectrum of the syndrome that is PCOS to
include how to make the diagnosis and differentiate from other
causes of menstrual irregularity and androgen excess.
To appreciate the role of insulin resistance and the long-term
health implications for women with PCOS.
To understand how to manage the issues that may affect a woman
in different ways at different times in her life, namely menstrual
cycle irregularity, hyperandrogenism and infertility.
A contentious issue is the appropriateness to deny fertility
treatment based upon a cut-off for body mass index (BMI), when
BMI is a crude measure of metabolic risk and the risks of
conception at a high BMI are not absolute. This also has to be
balanced against the decline in fertility with age which may have an
To what extent should young women who are found to have
polycystic ovaries on ultrasound scan but without any features of
the syndrome be advised about the potential for developing
problems in the future?
Should relatives of individuals with PCOS be screened for either
PCOS or metabolic syndrome (the latter may apply to male
anovulatory infertility / hyperandrogenism / menstrual
irregularity / ovulation induction / polycystic ovary syndrome
Please cite this paper as: Balen AH. Polycystic ovary syndrome (PCOS). The Obstetrician & Gynaecologist 2017;19:119–29. DOI:10.1111/tog.12345
Polycystic ovary syndrome (PCOS) is a far reaching
condition that has a number of reproductive and general
health implications; furthermore, it is the commonest
endocrine condition to affect women with an estimated
prevalence of 10–15% (depending on the population studied
and the diagnostic criteria used – see below).
of PCOS include menstrual cycle disturbance and features of
hyperandrogenism (hirsutism, acne and alopecia), with
associated fertility problems, obesity and psychological
There is signiﬁcant heterogeneity of presentation,
such that signs and symptoms manifest across a spectrum
and their severity may vary (Box 1). Ovarian
hyperandrogenism is thought to have genetic origins with
ampliﬁcation in some by hyperinsulinaemia secondary to
insulin resistance, which in turn may be promoted by
The primary presenting complaint itself is subject to
change depending on the age and needs of the patient; for
example, acne may be the primary concern during
adolescence, whereas reduced fertility may be the main
concern for an older woman. PCOS may also be associated
with an increased risk of developing type II diabetes,
metabolic syndrome and endometrial cancer.
symptoms of PCOS may have a profound impact on
Options for treatment include
lifestyle advice and a range of therapies depending upon
the constellation of an individual’s problems.
PCOS appears to be underdiagnosed and, as a result,
patients may not be managed appropriately.
management of PCOS may require the collaboration of a
variety of healthcare professionals, ranging from primary care
ª 2017 Royal College of Obstetricians and Gynaecologists
The Obstetrician & Gynaecologist