Abstract
The polycystic ovary syndrome, described first as the association
of bilateral polycystic ovaries and amenorrhoea, oligomenorrhoea,
hirsutism and obesity, was later shown to be a complex metabolic syndrome.
The first purpose of this study was to investigate the occurrence
of hyperinsulinaemia and the severity of insulin resistance and
glucose tolerance disorders in polycystic ovary syndrome by means of
the oral glucose tolerance test and the euglycaemic hyperinsulinaemic
clamp. The next goal was to investigate whether women with polycystic
ovary syndrome would benefit from insulin-sensitising drugs, and
in particular to compare the effects of metformin and a contraceptive
pill containing ethinyl oestradiol and cyproterone acetate. Altogether,
81 women with polycystic ovary syndrome and 34 healthy control subjects
were involved in the study.
Marked impairment of insulin sensitivity in obese subjects
with polycystic ovary syndrome, including a decrease of both cellular
oxidative and non-oxidative utilisation of glucose, and a slight non-significant
decrease of insulin sensitivity in non-obese subjects was observed.
Both non-obese and obese subjects with polycystic ovary syndrome
exhibited increased abdominal obesity compared with the controls,
confirming the fact that obesity, in particular abdominal obesity,
is an important contributor in the development of insulin resistance
in this syndrome.
Metformin alleviated hyperandrogenism by essentially decreasing
ovarian, but not adrenal androgen secretion. The improvement of
hyperandrogenism and ovarian function seemed to be mediated by the
improvement of hyperinsulinaemia, which resulted itself from subtle
improvements in both hepatic insulin extraction and insulin sensitivity.
Metformin decreased abdominal obesity and the release of free fatty
acids from adipose tissue, and improved ovarian cyclicity and fertility.
The transient decrease in serum leptin levels observed may have
some role in the improvement of ovarian function. The contraceptive
pill significantly improved hyperandrogenism and hirsutism, and
it slightly affected glucose metabolism. Thus, it could be the treatment
of choice in women with hirsutism problems and no fertility hopes.
Metformin could be the drug of choice for women with polycystic
ovary syndrome who wish to conceive. Because of its beneficial metabolic
effects, the value of metformin in reducing the risk of cardiovascular
diseases in polycystic ovary syndrome needs to be further studied