Menstrual Cycle Research Paper

INTRODUCTION

The most blazing feature of female reproductive system is the shedding of uterine epithelium at regular interval along with bleeding which is termed as Menstruation and the cycle of events occurring regularly is menstrual cycle.1

(A physiological cycl)e generally starts at puberty (menarche) and ends at age of 45 years (menopause). A monthly cycle which is related to ovulation and ovarian hormones. It is counted from the day on which menstrual bleeding begins. The average blood loss is35 ml. This cycle is generally 21-35 days long and consist of four phases -:

1. MENSTRUAL PHASE-: uterus sheds its inner lining and this immediate cause of endometrial necrosis is spasm of spiral arteries for several hours. In the meantime, when vessel

It Stimulates respiration and the alveolar Pco2 in women during luteal phase of menstrual cycle.8,9

It is to be recognized that women for an unknown reasons becoming more affected with lung diseases like asthma, obstructive pulmonary disease and fibrosis.10

Based on Lung Function Tests pulmonary diseases are categories into two types -:

1. Obstructive diseases

Diseases of lungs, which mainly produce airway obstruction, are grouped as obstructive airway diseases. It is an impairment of ventilation characterized by diffuse narrowing of bronchial tubes causing obstruction to air flow. It has been seen that forced expiratory volume in first second (FEV1) is decreased in persons suffering from diffuse obstructive disorders that deteriorate their pulmonary function tests. Bronchial asthma, emphysema, chronic bronchitis are important disorders came under this group

2. RESTRICTIVE DISEASES

Diseases which interfere with normal ventilation by restricting the expansion of thoracic cage, lungs and pleura are included in this group. Total lung capacity is decreased in this disease. The conditions like kyphoscoliosis, pleural effusion result in compression of lung and diminished expansion of thoracic

It has been observed by DA Bayliss, DE Millhorn, that Mechanisms underlying the stimulation of respiration by progesterone were similar to those mediating its reproductive effects. They indicate that the respiratory responses to progesterone is mediated at hypothalamic sites through Estrogen-dependent (E2) progesterone receptor (PR) mediated mechanisms requiring RNA and protein synthesis i.e. Gene expression. The E2 dependence of the respiratory response to progesterone is likely a consequence of the demonstrated induction of PR mRNA and PR in hypothalamic neurons by E2.16,17

Progesterone also decreases the alveolar and arterial pCo2 in luteal phase of menstrual cycle and provides strength to smooth muscles by acting as a smooth muscle relaxant.18

For the assessment of pulmonary functions FVC, FEV1, FEV1/FVC % are measured and according to one of the study all those parameters mentioned above are increasing significantly during the luteal phase in which progesterone level is high as compared to other phases of menstrual cycle19

All these evidences show that in luteal phase of menstrual cycle, there is a presence of relationship between changes in pulmonary function with progesterone. Different observations have shown that there is no increase in respiratory function parameters after addition of progesterone during different phases of menstrual