The Relationship of Insulin Resistance and Polycystic Ovary Syndrome: Effects of Metformin Therapy and ovarian Drilling

Document Type : Original Article

Authors

1 Department of Physiology , Faculty of Medicine, Assiut University

2 Department of Obstetrics & Gynecology, Faculty of Medicine, Assiut University

Abstract

Background: Polycystic ovary syndrome (PCOS) is a complex reproductive
endocrine-metabolic disorder and insulin resistance (IR) is a common feature of it.
Objective: To clarify the pathophysiological mechanisms of POCS, highlight its basic
relationship with IR and to investigate the efficacy of metformin therapy and ovarian
drilling in these cases. Patients and Methods: Thirty two PCOS patients (sixteen
received metformin 850 mg twice daily for four months[group 1] and sixteen
underwent laparoscopic ovarian drilling [group 2]) and fifteen healthy controls were
included in this study. Body mass index (BMI) evaluation followed by ultrasound
examination for measurement of antral follicles count (AFC) in both ovaries, oral
glucose tolerance curve, fasting blood glucose, insulin and glucose / insulin ratio
(G/I) were measured in addition to serum total testosterone (T), leutinizing hormone
(LH) and insulin like growth factor-1 (IGF-1) for all subjects. These parameters were
reevaluated again 4 months after either types of treatment. Results: PCOS patients
had significant increase BMI, T, LH, IGF-1, fasting blood glucose, insulin level and
AFC but G/I ratio was significantly lower. Significant negative correlations between
fasting G/I ratio and either of BMI, T, and AFC respectively were evident. Impaired
fasting glucose level at baseline was observed in PCOS patients while after metformin
and laparoscopic drilling it was significantly improved. Metformin significantly
decreased BMI, serum T, LH levels, IGF-1 and AFC and increased the G/I ratio
versus pretreatment values. Also, ovarian drilling has similar but less obvious effects.
Conclusion: IR plays a vital pathophysiological role in PCOS patients as manifested
by causal relationship between insulin resistance and metabolic and reproductive
changes of PCOS. Metformin and ovarian drilling potentially improve these changes.