Physiologic changes of pregnancy . DINA AKEEL

AIMS TO GAIN AN UNDERSTANDING OF THE PHYSIOLOGICAL CHANGES THAT OCCUR DURING PREGNANCY

Organ systems Cardiovascular system Pulmonary system Genital tract Urinary system Endocrine system Gastrointestinal Tract Skin

CHANGES ARE DUE TO ALTERATIONS IN HORMONAL PRODUCTION CIRCULATION METABOLISM

HORMONES OESTROGEN Produced in corpus luteum Produced by placenta after 12 weeks Responsible for growth particularly of uterus and breasts

progesterone Produced in corpus luteum and then the placenta Relaxes smooth muscle Inhibits uterine contractions until uterus is prepared for labour Regulates storage of body fat

Maternal changes - anatomical and physiological Cardiovascular changes increase in SV increase in cardiac output increase in HR at given work load increase in blood volume (mostly during latter half of pregnancy) Uterus may compress large blood vessels reducing venous return

Circulatory System The cardiovascular system includes the heart, blood, arteries, and veins. It delivers oxygen and nutrients to all parts of the body, and to the growing baby. As a result, the pregnant soldier's heart becomes more efficient at pumping the blood to her body and to the baby. When exercising, the soldier should not exercise to the point of exhaustion or breathlessness. This is a sign that your body cannot get the oxygen supply it needs, which effects the oxygen supply to the baby as well. The soldier should not engage in activities that involve low oxygen states, such as scuba diving or mountain climbing. Is exercise safe for the baby? One of the major concerns about exercise during pregnancy is the question of diversion of maternal blood flow away from the uterus to the skeletal muscles during moderate and vigorous activity. It is believed that in moderate recreational exercise, the diversion is approximately 50 percent and in competitive athletic events can be 70-80 percent. There is no research documentation of harm to the fetus, from the diversion of uterine blood flow, in soldiers who participate in regular moderate-to-high intensity exercise. The probable reason for this lack of detrimental fetal outcomes is the feto-protective, more-than-additive combination of increased blood plasma due to both aerobic training effect and pregnancy. This over-expansion reduces the fall in visceral gut blood flow and helps maintain fetal circulation during exercise. The increased red blood cells associated with exercise, as well as compensatory mechanisms of the placenta in well-conditioned, highly-fit soldiers, also helps account for the ability of the cardiovascular system to deliver needed nutrients.

Supine hypotension related to Venal cava syndrome This leads to dizziness, air hunger, nausea

Total body water Increases 6-8 L Increases by 40 % Normal body water 2/3 intracellular 1/3 extracellular ¾ interstitial ¼ intravasular 2/3 increase is extravascular

Respiratory system Mechanical Consumption Stimulation diaphragm Increase in needed oxygen Stimulation Progesterone stimulation

Physiologic changes - increase respiratory rate RESPIRATORY SYSTEM increase respiratory rate increased oxygen consumption common are nasal stuffiness, nosebleeds due to Increased vascular swelling to nose Changes that occur in the resp system are necessary to meet the inc o2 needs of the dev fetus. See slide. Hayfever symptoms Increased vascular swelling to nose/ may cause nose bleeds, difficulty breathing etc, Cool mist humidifiers Commercially prepared saline spray Capillaires inside the nose get engorged with blood during pregnancy causing nasal congestion and epistaxisis. Diaphram elevates 4 cm. Transverse diameter increases 2 cm. Anterioposterior diameter increases 2cm. Oxygen consumption increases 15-25% Tidal volume increases 50% Respiratory rate increases slightly Increased vascularity entire upper tract 14

Respiratory Consumption O2 consumption Increases 15-20 % 50 % of this increase is required by the uterus Despite increase in oxygen requirements, with the increase in Cardiac Output and increase in alveolar ventilation oxygen consumption exceeds the requirements. .

Physiologic changes - Digestive system slow due to progesterone GASTROINTESTINAL Digestive system slow due to progesterone Nausea and vomiting Ptyalism: increase salivation Heartburn Hemorrhoids Prolonged gallbladder emptying time may lead to gall stones Bile salt buildup may lead to itching. Digestive system slow due to progesterone May be due to increased HCG and estrogen Many theories about cause of nausea Gi changes are a result of the hormonal changes and inc fundal size puts pressure on internal organs Ptyalism – inc salivation 16

Gastrointestinal Tract Displacement of the stomach and intestines Appendix can be displaced to reach the right flank Gastric emptying and intestinal transit times are delayed secondary to hormonal and mechanical factors Vascular swelling of the gums Hemorrhoids due to elevated pressure in veins

Physiologic changes - BMR increases by 20-25 % during pregnancy METABOLISM BMR increases by 20-25 % during pregnancy Recommended weight gain – 25-35 lb Overweight – 15-25 lb Underweight – 25-35 lb Need for increased iron, calcium, fat, and protein 1ST TRI 3-4 LBS/MONTH 2ND 1 LB /WK 3RD 8-10 TOTAL TRI 19

Genital Tract Increased vascularity and hyperemia Increased secretions Vagina Perineum Vulva Increased secretions Characteristic violet color of the vagina Chadwick’s sign Increased length to the vaginal wall Hypertrophy of the papillae of the vaginal mucosa

Changes in the cervix Length remains the same Increase in width Softening after third month due to oestrogen Increased vascularity Increased cervical mucosa Increased glandular function

uterus grows to 30x23x20 at term weight increases to 900gms hypertrophy.. Oestrogen causes cells to increase until 20 weeks gestation Hyperplasia:- number of cells increase under the influence of oestrogen .

Relative Uterus Size During Pregnancy Figure 28.15

PLASMA VOLUME Increases from 10th week of pregnancy variable related to parity, fetal weight and number Reaches maximum level approx 50% above non-pregnant levels at 32-34 weeks then maintained

50% rise in plasma volume 20% rise in red cell mass Heamodilution: Physiological anaemia Most apparent at 32-34 weeks

RENAL SYSTEM DILATION OF THE RENAL VESSELS DUE THE EFFECTS OF PROGESTERONE INCREASED RENAL BLOOD FLOW GFR INCREASES BY 60% IN EARLY PREGNANCY

Urinary Changes Kidneys grow and filter more blood as the blood volume increases Become more susceptible to bladder and kidney infections Bladder becomes compressed causing frequent urination and incontinence Help for frequent urination: Keep drinking large amounts of water Plan for bathroom breaks before the urge arises Avoid drinking a lot of fluids before bed Expect to have frequent urination day and night Do Kegel exercises regularly If burning, pain or blood occurs upon urination, tell your health care provider

Wajed Hatamleh RN, MSN, PhD. Physiologic changes - URINARY TRACT Increased glomerular filtration rate Frequency Infection : Smooth muscle of bladder relaxes/stasis Urinary tract changes result form the inc blood volume and glom filtration rate and inc fundal size puts pressure on internal organs More susceptible to infection dt dec blood flow and traumaGFR raises by 50% Increased renal clearance leads to lowered BUN and nonprotein nitrogen values. Renal plasma blood flow increases 50% Glomerular Filtration Rate increases Bicarbonate increased excretion Creatinine increased excretion Renal pelves and ureters dilate Smooth muscle of bladder relaxes/stasis Sugar may spill at 160/protein PIH Wajed Hatamleh RN, MSN, PhD. 28

Hydration is a major concern during maternal exercise. WATER, WATER, WATER Hydration is a major concern during maternal exercise. Provide a ready source of water Encourage frequent water breaks Hydration is a major concern during maternal exercise. ELs must provide a ready source of water for pregnant soldiers and encourage frequent water breaks. EMPHASIZE THIS! Water contributes to the cooling process Ensures adequate increase in blood volume Drink before and during and after exercise Consume at least 2 quarts of water or other fluid per day Very active soldiers should drink water until their urine is clear During hot, humid weather, exercise should only be done in a cooled or air-conditioned room.

Skin changes Chloasma or melasma gravidarum Striae Linea nigra

Skin Changes Stretch marks Dark pigmented line on there abdomen which is called Linea Nigra Pigment changes on their face and neck Small blood vessels in the face, neck and upper chest MOST OF THESE RESOLVE AFTER PREGNANCY Stretch marks are common over breasts, abdomen and hips Many woman get a dark pigmented line on the abdomen called a Linea Nigra which resolves after pregnancy Occasionally, women will have pigment changes on their face and neck. This also resolves after pregnancy. Small blood vessels may appear in the face, neck, and upper chest. These are more common in white women and less common in women of other skin colors. These usually resolve after pregnancy.

Melasma

Melasma

Melasma Also known as the mask of pregnancy More common in dark skin people More pronounced in the summer Fades a few months after delivery Repeated pregnancy can intensify Can occur in normal non-pregnant women with harmless hormonal imbalances or women on OCPs or depo

Striae

Striae Reddish slightly depressed Breasts, thighs, and abdomen In future pregnancies they appear as glistening, silver lines

Linea nigra