Metformin Effects on Metabolic, Vitamin B12, Iron, Erythropoietin, and Hematological Parameters in Women With PCOS

Summary

This double-blind, placebo-controlled, parallel-group randomized controlled trial evaluated changes in metabolic, vitamin B12, iron-status, erythropoietic, and hematological parameters among women with polycystic ovary syndrome (PCOS) receiving metformin therapy. Women aged 18-40 years with a diagnosis of PCOS confirmed by a specialist in Obstetrics and Gynecology were randomly assigned in a 1:1 ratio to either a metformin intervention group or a matching placebo group. Participants in the metformin group received a total daily dose of 1500 mg metformin, administered in three divided doses with meals, while participants in the control group received a matching placebo. Both groups continued to receive routine clinical care. Clinical and laboratory assessments were performed at baseline, 3 months, and 6 months. The study evaluated metabolic measures, including fasting blood glucose, serum insulin, HOMA-IR, total cholesterol, triglycerides, LDL-C, HDL-C, and body mass index. Iron-status measures included serum iron, total iron-binding capacity, ferritin, and transferrin saturation. Serum vitamin B12 and erythropoietin were also assessed, together with hematological parameters including hemoglobin, hematocrit, red blood cell indices, white blood cell counts and differential counts, and platelet count. The study enrolled 400 participants, with 200 participants initially allocated to each treatment group. After loss to follow-up, 300 participants completed the required assessments and were included in the final longitudinal analysis, with 150 participants in each group. The study was designed to characterize longitudinal changes in metabolic, nutritional, iron-related, erythropoietic, and hematological parameters during six months of metformin therapy in women with PCOS.

Timeline

Start

2025-08-01

Primary completion

2026-02-01

Completion

2026-08-01

Publications

• Results Escobar-Morreale HF. Iron metabolism and the polycystic ovary syndrome. Trends Endocrinol Metab. 2012 Oct;23(10):509-15. doi: 10.1016/j.tem.2012.04.003. Epub 2012 May 10.
• Results Greibe E, Trolle B, Bor MV, Lauszus FF, Nexo E. Metformin lowers serum cobalamin without changing other markers of cobalamin status: a study on women with polycystic ovary syndrome. Nutrients. 2013 Jul 5;5(7):2475-82. doi: 10.3390/nu5072475.

Drugs

Indications