Practice Committee
of the American Society for Reproductive Medicine does not recommend Metformin alone
for ovulation induction as a first line therapy in women with PCOS. The guidelines
were published in Journal Fertility and Sterility Epub ahead of print.
Metformin is
a biguanide used as an oral insulin lowering agent in type2 diabetes, but also
used enthusiastically in women with PCOS because of shared pathophysiology of
insulin resistance in both.
A review of
clinical data has however failed to support its use as first-line therapy in
PCOS and for treating hirsutism.
A review of
RCTs showed that metformin alone only increases the ovulation rate but letrozole
and clomiphene citrate alone are more effective in terms of ovulation,
pregnancy and live-birth rates.
When
Metformin alone was compared with Clomiphene alone, evidence suggested that it
is less effective for ovulation and live-birth rates.
Metformin is
recommended as a second line therapy in combination with gonadotrophins for clomiphene
citrate resistant and/or obese PCOS patients. However, there is good evidence
that live pregnancy rate remains the same with this combination.
Metformin
can only be used as first line therapy if facilities are not available to
monitor the more effective therapies of clomiphene citrate and letrozole.
A 2016 analysis of evidence to help WHO formulate global treatment guidelines for the
management of anovulatory infertility in women with polycystic ovary syndrome
(PCOS) also does not recommend metformin alone as first-line therapy. Its use
is recommended as an adjunct to GnRH-agonist long protocol IVF or ICSI
treatment to reduce the risk of ovarian hyperstimulation syndrome.
Metformin
should be stopped as soon as pregnancy is achieved because it does not help in
reducing routine pregnancy complications. The Endocrine Society and NICE Guidelines on PCOS state that the routine use of metformin during pregnancy in
women with PCOS is unwarranted, although it may be useful to treat gestational
diabetes, and therefore recommended against the use of metformin for the
prevention of pregnancy complications.
