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Nitric Oxide, a product of the vascular endothelium, plays a key second messenger role in the convergent mechanism of estrogen and progesterone via the NO-cGMP pathway. Innumerable studies have documented the fluctuations in nitric oxides in response to the varying levels of estrogen and progesterone mostly in animal models . Herein, an attempt was made, perhaps for the first time, to study the same in different phases of the menstrual cycle in healthy human females belonging to the reproductive age group. In this study, fasting blood samples were collected from 71 healthy female volunteers on three different days, each representative of the different phases of the cycle and serum estrogen, progesterone and the nitrate-nitrite ratio were measured on the respective days. This book will be particularly useful for those involved in clinical researches concerned with infertility and also in evaluating the effects of exogenous hormonal supplementation not only in menopause and other gynecological disorders but also in recent treatment of Alzheimers, amenorrheic bone loss etc.

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Dr. Sharmistha Chatterjee, MBBS, MD. Studied MBBS at R.G.Kar Medical College, University of Kolkata and MD in Biochemistry at Medical College, West Bengal University of Health Sciences, Kolkata. Presently, Assistant Professor, Department of Biochemistry, College of Medicine and Sagore Dutta Hospital, Kolkata.

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