Endocrine Abstracts

Introduction: Polycystic ovarian syndrome (PCOs) is a common cause of ovarian dysfunction in women with anovulation. Vitamin D plays a physiologic role in reproduction including ovarian follicular development and luteinization via altering anti-müllerian hormone (AMH) signalling, follicle-stimulating hormone sensitivity and progesterone production in human granulosa cells. Low vitamin D levels may exacerbate the symptoms of PCOS, including insulin resistance, ovulatory, menstrual irregularities, infertility, obesity and elevate the risk of cardiovascular diseases.

Aim: Aim of the study is to estimate the impact of vitamin D supplementation on insulin resistance, using HOMA IR calculation, in PCOs patients.

Materials and methods: The study includes 60 patients with PCOs and normal levels of vitamin D (between 50–100 ng/ml) divided in four groups. Before treatment, we measured fasting glucosae and insulin levels and calculate HOMA IR to all patients. Then we divided patients in four treatment groups: MD- treated with MET (metformin) plus LGD(low glycaemic diet-1800 Kcal), MDW- treated with MET plus LGD plus vitamin D supplementation 14000 ij/weekly, MDD2- treated with MET plus LGD plus vitamin D supplementation 2000 ij/daily and MDD4- treated with MET plus LGD plus vitamin D supplementation 4000 ij/daily. During period of six months we followed progesterone levels on 21th day of menstrual cycle. After six months of treatment we evaluated fasting glucosae, fasting insulin and HOMA IR.

Results: After treatment mean values of HOMA IR in MD group was reduced from 2.93±1.43 to 2.31±1.01(reduced for 21%), in MDW group was reduced from 2.84±0.93 to 2.30±1.22 (reduced for 19%), in MDD2 group was reduced from 2.89±1.21 to 2.19±1.44 (reduced for 24%) and in MDD4 group was reduced from 2.99±1.40 to 1.97±0.95(reduced for 34%) (P<0.05). Also number of biochemical confirmed ovulations, during six months of treatment, was the highest in MDD4 group, 2.45 ovulations per patients, then in MDD2 group, 1.61 ovulations/patients, while in the MD i MDW groups were similar 1.14 and 1.11 ovulation/patients.

Conclusion: In patients with metformin and diet treated polycystic ovarian syndrome, weekly supplementation with vitamin D have no additional effect on the reduction of insulin resistance. However, daily supplementation with vitamin D has a significant effect on the additional reduction of insulin resistance, especially at a dose of 4000 IU per day. Also, the same dose significantly improves ovulation in patients who are already treated with metformin and diet.