PHYSIOLOGICAL CHANGEGS PHYSIOLOGICAL CHANGEGS OF PREGNANCYOF PREGNANCY

AHMED ABDULWAHABAHMED ABDULWAHAB

Maternal physiologic adjustment to Maternal physiologic adjustment to pregnancy are designed to support the pregnancy are designed to support the requirements of fetal needs without affecting requirements of fetal needs without affecting maternal well-being.maternal well-being.

The normal values of several hematologic, The normal values of several hematologic, biochemical,biochemical, and physiologic indices during and physiologic indices during pregnancy differ markedly from those in the pregnancy differ markedly from those in the non pregnant range and also according to non pregnant range and also according to duration of pregnancy. duration of pregnancy.

ALIMENTARY TRACT.ALIMENTARY TRACT. Appetite is usually normal without changesAppetite is usually normal without changes Pica. Dietary craving or aversion for non Pica. Dietary craving or aversion for non

nutritional substances .nutritional substances . Mouth , ptyalism usually associated with Mouth , ptyalism usually associated with

nausea of pregnancy.nausea of pregnancy. Dentition , gum become soft and edemtous.Dentition , gum become soft and edemtous.

STOMACH.STOMACH. Tone and motility decreases because of the Tone and motility decreases because of the

effect the PROGESTERONE hormone and effect the PROGESTERONE hormone and emptying time of the stomach is prolonged emptying time of the stomach is prolonged

Gastro esophageal junction sphincter tone Gastro esophageal junction sphincter tone decreases leading to heart burns decreases leading to heart burns

Gastric acid secretion decreases and peptic Gastric acid secretion decreases and peptic ulcer disease decreases.ulcer disease decreases.

Small bowel motility decrease and increases Small bowel motility decrease and increases iron absorption .iron absorption .

Colon, there is decrease motility resulting in Colon, there is decrease motility resulting in constipation ,increase water and sodium constipation ,increase water and sodium absorption and dilatation of hemorrohdial absorption and dilatation of hemorrohdial veins .veins .

Liver Liver Signs of normal pregnancy that may mimic Signs of normal pregnancy that may mimic

liver disease liver disease

Spider angiomata and palmer erythema due Spider angiomata and palmer erythema due to increase estrogen level .to increase estrogen level .

Decrease albumin and increase alkaline Decrease albumin and increase alkaline phosphatase .phosphatase .

Nausea and vomiting usually in first Nausea and vomiting usually in first trimester trimester

Respiratory system .Respiratory system . Mechanical changes .Mechanical changes . Subcostal angles transverse chest diameter, Subcostal angles transverse chest diameter,

and chest circumference increases and the and chest circumference increases and the diaphragm level is pushed up .diaphragm level is pushed up .

Lung volume and pulmonary function .Lung volume and pulmonary function . Tidal volume increase inspiratory capacity Tidal volume increase inspiratory capacity

increases, vital capacity decreases increases, vital capacity decreases

Skin .Skin . Vascular changes , due to estrogen.Vascular changes , due to estrogen. Spider angiomata ,palmer erythema.Spider angiomata ,palmer erythema. Striae gravidarum Striae gravidarum Pigmentation changes ,increases Pigmentation changes ,increases

melanocyte- stimulating hormones .melanocyte- stimulating hormones . Darkening of nipples, areolae ,umbilicus, Darkening of nipples, areolae ,umbilicus,

axillae , perineum and linea nigra axillae , perineum and linea nigra

Chloasma or mask of pregnancy.Chloasma or mask of pregnancy. Pigmented navi.Pigmented navi. Abdominal wall there is separation of the Abdominal wall there is separation of the

recti muscles recti muscles

Urinary system.Urinary system. Anatomic changes.Anatomic changes. Kidneys increase in both length and weight.Kidneys increase in both length and weight. Renal pelvis increase resulting in Renal pelvis increase resulting in

physiological hydro nephrosis .physiological hydro nephrosis . Ureters dilate starts by 8 weeks gestation.Ureters dilate starts by 8 weeks gestation. Right ureter is larger than the left causing Right ureter is larger than the left causing

hydroureter and urinary stasis .hydroureter and urinary stasis .

Dilatation is commonly above the pelvic brim.Dilatation is commonly above the pelvic brim. Consequences. Consequences. Increase risk of pyelonephritis and asymptomatic Increase risk of pyelonephritis and asymptomatic

bacteriuria bacteriuria Renal function tests.Renal function tests. Renal plasma flow, glomerular filtration rate and Renal plasma flow, glomerular filtration rate and

creatinine clearance are all increase more than creatinine clearance are all increase more than 50%,50%,

Blood urea creatinine and uric acid all decreaseBlood urea creatinine and uric acid all decrease

Glucosuria is common in normal pregnancy Glucosuria is common in normal pregnancy and has no correlation with blood sugar and has no correlation with blood sugar level .level .

Aminoaciduria .Aminoaciduria . Increase excretion of water soluble vitamin Increase excretion of water soluble vitamin

folate and vitamin B 12folate and vitamin B 12

Cardiovascular system.Cardiovascular system. There is a change in the position of the There is a change in the position of the

heart.heart. Normal changes in heart sound include.Normal changes in heart sound include. Exaggerated splitting of S1Exaggerated splitting of S1 Gallop pulse in 90% of normal pregnancy Gallop pulse in 90% of normal pregnancy Systolic ejection murmur .Systolic ejection murmur . Mammary souffleMammary souffle

EKG is unchanged except for left axis EKG is unchanged except for left axis deviation.deviation.

Increase cardiac output by 40% due to Increase cardiac output by 40% due to increase in both stroke volume and heart increase in both stroke volume and heart rate .rate .

Cardiac output depends on maternal Cardiac output depends on maternal position ,it is lowest when in supine position ,it is lowest when in supine position . Supine hypotension syndrome.position . Supine hypotension syndrome.

Blood pressure .Blood pressure . There is a progressive decrease in both There is a progressive decrease in both

systolic and diastolic pressure , after 24 systolic and diastolic pressure , after 24 weeks the pressure gradually increase and weeks the pressure gradually increase and return to non pregnant level by term.return to non pregnant level by term.

Central venous pressure remain Central venous pressure remain unchanged .unchanged .

Hematological changes .Hematological changes . Plasma volume increase 50% by term it Plasma volume increase 50% by term it

begins by 10 weeks and plateaus at 30 begins by 10 weeks and plateaus at 30 weeks gestation there is more increase in weeks gestation there is more increase in multiple pregnancy or larger fetuses .multiple pregnancy or larger fetuses .

Red blood cell increases by 30% at term .Red blood cell increases by 30% at term . Physiological anemia result because the Physiological anemia result because the

plasma volume increases more than RBC.plasma volume increases more than RBC.

Leukocyte and platelets.Leukocyte and platelets. White blood cell mostly PMN granulocytes White blood cell mostly PMN granulocytes

increases progressively in pregnancy.increases progressively in pregnancy. Platelets slightly decrease.Platelets slightly decrease. Coagulation system.Coagulation system. Pregnancy is a hyper coagulable state.Pregnancy is a hyper coagulable state. Fibrinogen increase by 50% .Fibrinogen increase by 50% . Factors V11 ,V111,1X,and X all increasesFactors V11 ,V111,1X,and X all increases

Iron metabolism .Iron metabolism . Absorption depends on pregnancy state and Absorption depends on pregnancy state and

bone marrow iron stores ,40% absorption in bone marrow iron stores ,40% absorption in the iron deficient state .the iron deficient state .

The total iron requirement is 1000 mg and The total iron requirement is 1000 mg and the daily requirement is 3.5 mg .the daily requirement is 3.5 mg .

Maternal iron deficiency does not affect fetal Maternal iron deficiency does not affect fetal iron stores because of active iron transport iron stores because of active iron transport across the placenta.across the placenta.

Endocrine and metabolic changes.Endocrine and metabolic changes. Thyroid gland .it increase in size.Thyroid gland .it increase in size. Thyroid binding globulin increases as a result of estrogen Thyroid binding globulin increases as a result of estrogen

stimulation of the liver .stimulation of the liver . The active unbound form remain unchanged or slightly The active unbound form remain unchanged or slightly

decrease.decrease. The following thyroid hormones do not cross the placenta The following thyroid hormones do not cross the placenta

T3, T4,and TSH , thyroid immunoglobulins crosses the T3, T4,and TSH , thyroid immunoglobulins crosses the placenta as well ass anti thyroid medicationplacenta as well ass anti thyroid medication

Adrenal gland.Adrenal gland. Total and free cortisol increase by two foldTotal and free cortisol increase by two fold Aldosterone secretion is markedly increase .Aldosterone secretion is markedly increase . Deoxycortisone level increases.Deoxycortisone level increases. Pancreas there hypertrophy and hyperplasia Pancreas there hypertrophy and hyperplasia

.. Fasting blood glucose is lower than in non Fasting blood glucose is lower than in non

pregnant state pregnant state