Anatomical and Physiological Changes During Pregnancy PDF

Anatomical and physiological changes during Pregnancy  Introductory Comments   Not possible to cover “all” the changes that occur during pregnancy!  We will highlight some of the important changes that occur, affecting some of the major organ systems  Key concept: one nee...

Anatomical and physiological changes during Pregnancy  Introductory Comments   Not possible to cover “all” the changes that occur during pregnancy!  We will highlight some of the important changes that occur, affecting some of the major organ systems  Key concept: one needs to know “normal” to be able to diagnose and manage the common problems in pregnancy!  This may be of personal importance some day!  Anatomical and physiological changes during Pregnancy:  During pregnancy hormones increase. primarily Progesterone, and Estrogen, causing a variety of physiological changes, which become increasingly more prominent as pregnancy continues.  There are two reasons for these changes: 1. to provide a suitable environment for the nutrition, growth and development of the fetus. 2. to prepare the mother for the process of pregnancy and delivery. Weight Gain in Pregnancy  Normal weight gain can be 9.5-14.5 kg in average patient and more in twin pregnancy.  Excess weight gain associated with variety of complications.  organs 1. Uterus: it increases in weight from 60 to 1000 g.  It increases in size from 6.5 to 32 cm.  Uterine expansion is caused by the growing fetus and increase in the connective tissue and the size and number of blood vessels 2. Cervix  During pregnancy, the cervix is closed. A mucous plug forms over the cervix providing a protective barrier between the vagina and the uterine content.  During labor, the cervix shortens and dilates to allow for passage of the fetus.  Breast Changes  Increased blood flow to breasts  Increased size  Increased ductal growth, Musculoskeletal Changes in Pregnancy  Ligament laxity throughout pregnancy, which may predispose to joint injury especially in the weight bearing joints of the back, pelvis and lower extremity.  Progressively more back pain.  Stretching of the abdominal muscles.  Dropping of the pelvic floor muscles as much as 2.5 cm. Postural changes Postural changes to accommodate for abdominal growth:  Forward head, rounded shoulders, increased lumbar lordosis, hyper-extended knees, and pronated feet.  Changes of the center of gravity result in change of balance.  Muscular changes as shortened hip flexors, low back muscles, and pectoralis.  Elongation may occur in the abdominal muscles, neck, and upper back muscles. This may promote stretch weakness or adaptive shortening.  Extra weight is placed on the pelvic floor.  Waddling gait may be observed due to softening of the ligaments (especially the sacroiliac and symphysis pubis).  No loss of bone density during pregnancy, but with repeated pregnancy there is tendency to bone decalcification.  Skin Changes  Striae gravidarum: due to overstretching of the skin, the elastic fibers may rupture together with small blood vessels, so red streaks appear. They are usually marked below the umbilicus, breast, buttocks and thighs. After labor, the red striae become silvery.  Hyperpigmentation effects Linea nigra (a line of pigmentation between the umbilicus and symphysis pubis) Mask of pregnancy (butterfly area): The skin on the upper cheeks and, often, on the forehead and upper lip, Increased nipple pigmentation.  Increased fine hair growth while pregnant  Palmar erythema  Gastrointestinal Changes  The enlarging uterus causes a gradual dis- placement of stomach and intestines. At term the stomach has attained a vertical position rather than its normal horizontal one.  These mechanical forces lead to increased intragastric pressures as well as a change in the angle of the junction, lead to (heart burn).  Common Changes in Pregnancy  Nausea and vomiting of pregnancy or “morning sickness” etiology is unknown  Increased tendency for gallbladder dysfunction with possible need for surgery,  Constipation  Respiratory system  As the uterus enlarges, the diaphragm is elevated as much as 4cm, and the rib cage is displaced upward and widens.  Abdominal muscles have less tone and are less active during the pregnancy, causing respiration to be more diaphragmatic. Cardiovascular System  As the uterus enlarges and the diaphragm becomes elevated, the heart is displaced upward and somewhat to the left with rotation on its long axis, so that the apex beat is moved laterally. The size of the heart appears to increase by about 12% Cardiac output increases around 50%  Renal Changes in Pregnancy  As the uterus enlarges, the urinary bladder is displaced upward and flattened in the anterior- posterior or diameter.  Pressure from the uterus leads to increased urinary frequency. Bladder vascularity increases and muscle tone decreases, increase in capacity up to 1500ml.  Loss of urinary control.  Varicosity  Some patients can develop significant discomfort from the dilated veins in the lower half of the body, interfering with exercise, and even normal daily activity. These women may benefit significantly from hydrotherapy.  Swimming, and gentle exercises in a swimming pool helps reduce the side effects of vein dilation by pushing fluids back into the body's trunk, and core.