Download 12-PHYSIOLOGICAL CHANGEGS OF PREGNANCY

PHYSIOLOGICAL CHANGEGS
OF PREGNANCY
AHMED ABDULWAHAB
 Maternal physiologic adjustment to
pregnancy are designed to support the
requirements of fetal needs without affecting
maternal well-being.
 The normal values of several hematologic,
biochemical, and physiologic indices during
pregnancy differ markedly from those in the
non pregnant range and also according to
duration of pregnancy.
 ALIMENTARY TRACT.
 Appetite is usually normal without changes
 Pica. Dietary craving or aversion for non
nutritional substances .
 Mouth , ptyalism usually associated with
nausea of pregnancy.
 Dentition , gum become soft and edemtous.
 STOMACH.
 Tone and motility decreases because of the
effect the PROGESTERONE hormone and
emptying time of the stomach is prolonged
 Gastro esophageal junction sphincter tone
decreases leading to heart burns
 Gastric acid secretion decreases and peptic
ulcer disease decreases.
 Small bowel motility decrease and increases
iron absorption .
 Colon, there is decrease motility resulting in
constipation ,increase water and sodium
absorption and dilatation of hemorrohdial
veins .
 Liver
 Signs of normal pregnancy that may mimic
liver disease
 Spider angiomata and palmer erythema due
to increase estrogen level .
 Decrease albumin and increase alkaline
phosphatase .
 Nausea and vomiting usually in first
trimester
 Respiratory system .
 Mechanical changes .
 Subcostal angles transverse chest diameter,
and chest circumference increases and the
diaphragm level is pushed up .
 Lung volume and pulmonary function .
 Tidal volume increase inspiratory capacity
increases, vital capacity decreases
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Skin .
Vascular changes , due to estrogen.
Spider angiomata ,palmer erythema.
Striae gravidarum
Pigmentation changes ,increases
melanocyte- stimulating hormones .
 Darkening of nipples, areolae ,umbilicus,
axillae , perineum and linea nigra
 Chloasma or mask of pregnancy.
 Pigmented navi.
 Abdominal wall there is separation of the
recti muscles
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Urinary system.
Anatomic changes.
Kidneys increase in both length and weight.
Renal pelvis increase resulting in
physiological hydro nephrosis .
 Ureters dilate starts by 8 weeks gestation.
 Right ureter is larger than the left causing
hydroureter and urinary stasis .
 Dilatation is commonly above the pelvic brim.
 Consequences.
 Increase risk of pyelonephritis and asymptomatic
bacteriuria
 Renal function tests.
 Renal plasma flow, glomerular filtration rate and
creatinine clearance are all increase more than
50%,
 Blood urea creatinine and uric acid all decrease
 Glucosuria is common in normal pregnancy
and has no correlation with blood sugar
level .
 Aminoaciduria .
 Increase excretion of water soluble vitamin
folate and vitamin B 12
 Cardiovascular system.
 There is a change in the position of the
heart.
 Normal changes in heart sound include.
 Exaggerated splitting of S1
 Gallop pulse in 90% of normal pregnancy
 Systolic ejection murmur .
 Mammary souffle
 EKG is unchanged except for left axis
deviation.
 Increase cardiac output by 40% due to
increase in both stroke volume and heart
rate .
 Cardiac output depends on maternal
position ,it is lowest when in supine position
. Supine hypotension syndrome.
 Blood pressure .
 There is a progressive decrease in both
systolic and diastolic pressure , after 24
weeks the pressure gradually increase and
return to non pregnant level by term.
 Central venous pressure remain unchanged
.
 Hematological changes .
 Plasma volume increase 50% by term it
begins by 10 weeks and plateaus at 30
weeks gestation there is more increase in
multiple pregnancy or larger fetuses .
 Red blood cell increases by 30% at term .
 Physiological anemia result because the
plasma volume increases more than RBC.
 Leukocyte and platelets.
 White blood cell mostly PMN granulocytes
increases progressively in pregnancy.
 Platelets slightly decrease.
 Coagulation system.
 Pregnancy is a hyper coagulable state.
 Fibrinogen increase by 50% .
 Factors V11 ,V111,1X,and X all increases
 Iron metabolism .
 Absorption depends on pregnancy state and
bone marrow iron stores ,40% absorption in
the iron deficient state .
 The total iron requirement is 1000 mg and
the daily requirement is 3.5 mg .
 Maternal iron deficiency does not affect fetal
iron stores because of active iron transport
across the placenta.
 Endocrine and metabolic changes.
 Thyroid gland .it increase in size.
 Thyroid binding globulin increases as a result of estrogen
stimulation of the liver .
 The active unbound form remain unchanged or slightly
decrease.
 The following thyroid hormones do not cross the placenta
T3, T4,and TSH , thyroid immunoglobulins crosses the
placenta as well ass anti thyroid medication
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Adrenal gland.
Total and free cortisol increase by two fold
Aldosterone secretion is markedly increase .
Deoxycortisone level increases.
Pancreas there hypertrophy and hyperplasia
.
 Fasting blood glucose is lower than in non
pregnant state