Physiologic changes during pregnancy can be local, affecting the reproductive organs, or systemic. The reproductive organs like the uterus, cervix, vagina, and breasts undergo changes to accommodate fetal growth. Systemic changes include increased blood volume, heart rate, and respiration rate. Hormonal changes impact many body systems and help the body adapt to support the developing fetus. The physiologic changes during pregnancy are normal adaptations essential for a healthy pregnancy.

1. PHYSIOLOGIC CHANGES
DURING PREGNANCY
112/2/2019
By Ephrem Yohannes

2. Outline
 Objectives
 Definition of physiologic changes during pregnancy
 Classification of physiologic changes during pregnancy
 Causes of physiologic changes during pregnancy
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3. Objectives
After completion of this session students will be able to:
 Define of physiologic changes during pregnancy
 List classification of physiologic changes during pregnancy
 Discuss causes of physiologic changes during pregnancy
312/2/2019

4. Physiologic Changes during Pregnancy
 There may be:
a) Local (to the reproductive organs) or
b) Systemic
 Are caused by several factors:
Maternal endocrine /hormonal
Fetal and placental endocrine
Fetal metabolic rate and physical demands
The women‘s physical adaptation to the changes
412/2/2019

5. 1. Changes of the reproductive organs
A. Uterus
At term, the uterus increased five times its normal size
Its length , depth , width, weight ,blood flow increases
In thickness of the walls from 1to 0.5cm will decrease
It displaced the abdominal contents
Its size usually reaches its peak at 38 weeks gestation
512/2/2019

6. B. Cervix
 It undergoes a marked softening (Goodell's sign)
 Increased in vasicularity and edematous
 Color bluish (pale pink –violet)
 A mucus plug, known as "operculum" is formed in the cervical canal
 What is the source and importance of this operculum?
Changes of the reproductive organs …cont’d
612/2/2019

7. C. Vagina:
 Color changes from normal light pink to a purple blue/deep violet
which is known as the "Chadwick's sign." due to increased circulation to
the vagina early in pregnancy
 Decreased in PH due to lactobacilli
 Increases in discharge how?
Changes of the reproductive organs …cont’d
712/2/2019
 (by the effect of progesterone hormone)
(changes glycogen to lactic
acid)

8. D. Ovaries
 The FSH :
 Ceases its activity due to the ⇧sed levels of estrogen and progesterone
 Prevents ovulation and menstruation
Changes of the reproductive organs …cont’d
812/2/2019

9. Changes of the breasts
 In early pregnancy, it feels full or tingle, and increase in size as pregnancy
progresses due to increase in estrogen ,progesterone and prolactin
 The areolas of the nipples darken and the diameter increases
 The surface vessels of it become visible due to increased
circulation/Hyper pgimentation
 By the 16th wk the breasts begin to produce colostrum
Changes of the reproductive organs …cont’d
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10. 1012/2/2019

11. Systemic
1. Changes of the skin /integumentary system
 Results from alterations in hormonal balance and mechanical stretching
 Includes :
Linea Nigra
 A dark line that runs from the umbilicus to symphysis pubis
 It is a hormone- induced pigmentation
 After delivery, it begins to fade, but it may not ever completely disappear
 Why if it doesn't completely dis appear?
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12. 1212/2/2019

13. 1. Changes of the skin /integumentary system…
 Striae Gravidarum (Stretch Marks)
 Pink /reddish steaks on sides the abdomen
 It may be due to the action of the adrenocorticosteroids
 It reflects a separation within underlying connective tissue of the skin
 It occurs over areas of maximal stretch--the abdomen, thighs, and breasts
 It will usually fade after delivery although they never completely disappear
Systemic…cont’d
1312/2/2019

14. Mask of Pregnancy (Chloasma)
 Is the brownish hyper pigmentation of the skin over the face and
forehead/ cheen
 It gives a bust look, especially in dark-complexioned women
 It begins about the 16th week of pregnancy and gradually increases
 Hyper pigmentation /darken over : nipple, Umbilicus, Axilla, perineal
 Sweat Glands?
Systemic…cont’d
1412/2/2019

15. 2. Changes of the circulatory system
 Blood Volume:
 ⇧ses gradually by 30 to 50 % (1500 ml OR 3 units)
 This results in ↓se concentration of RBCs and hemoglobin
 This explains why they need for iron during pregnancy
 Blood count is interpreted as anemia if the hemoglobin falls below
10.5 grams per 100 ml and HCT drops below 30%
 Utero-placental blood flow was found to increase progressively
during pregnancy. Estimates range from 500 to 750 mL/min
Systemic…cont’d
1512/2/2019

16. Systemic…cont’d
It returns to non-pregnant levels by 6 days post-
delivery.
There is often a sharp rise of up to 1 liter in
plasma volume, within maternal circulation, 24
hours after delivery
Heart rate is increased above non-pregnant
values by 15%
1612/2/2019

17. Cardiac Output:
 ⇧ses about 30% during the 1st and 2nd trimester
 Why cardiac decompensation is more common at 28 to 35 weeks ,
during labor and immediately after delivery ?
At 28 to 35 weeks of pregnancy the cardiac load are at their peak
During labor & immediately after delivery there is rapid
hemodynamic changes occur
 Change in output is reflected in the heart rate
 It usually increases by 10 beats per minute
Systemic…cont’d
1712/2/2019

18. Venous Return:
 The lower extremities are often hampered in the last months of
pregnancy due to the expanding uterus restricting physical movement
and interfering with the return of blood flow
 This results in swelling of the feet and legs
Systemic…cont’d
1812/2/2019

19. 3. Changes of the respiratory system
 The RR rises to 18 to 20 to compensate for ⇧sed maternal oxygen
consumption, which is needed for demands of the uterus, the placenta,
and the fetus
 Women may feel out of breath and may need to sit a moment to
catch their breath
 Nasal stiffness and epitaxis are common
 Diaphragm displaced up ward( up to 4cm)
 Increased chest diameter
 Lung volume and capacity increases
Systemic…cont’d
1912/2/2019

20. 4. Changes of body temperature
 A slight increase in body temperature in early pregnancy is noted
 The temperature returns to normal at about 16th week of gestation
 The patient may feel warmer or experience "hot flashes" caused by
increased hormonal level and basal metabolic rate
Systemic…cont’d
2012/2/2019

21. 5. Changes of the urinary system
 The kidneys work extra excreting the mother's own waste products plus
those of the fetus due to this enlarge
 There is an ⇧se in urinary output and a ↓se in the specific gravity
 The patient may develop urine stasis and pyelonephritis in the right
kidney.
 due to pressure on the right ureter resulting from displacement of the
uterus slightly to the right by the sigmoid colon
 Frequent urination is a complaint during the 1st through 3rd trimester
 As the uterus rises out of the pelvic cavity in early pregnancy, pressure
on the bladder ↓ses and frequency diminishes.
Systemic…cont’d
2112/2/2019
why?

22. 6. Changes of the skeletal system
 There is a realignment of the spinal curvatures to maintain balance
 It is due to ⇧se in size of the uterus and pressure on the abdominal wall
 The patient walks with head and shoulders thrust backward and chest
protruding outward to compensate
 This gives the patient a "waddling" gait and lordosis causes back ache
 There is a slight relaxation and ⇧sed mobility of the pelvic joints, which
allows stretching at the time of delivery
Systemic…cont’d
2212/2/2019

23. 7. Changes of the gastrointestinal system
 Anatomical change:
 As the pregnancy progresses, the uterus enlarges, it rises up and out of
the pelvic cavity
 This action displaces the stomach, intestines, and other adjacent organs
 Increased Appetite(pica)
 Gums edematous and softening why?
 Dental carries due to↓se in PH
 Epulis gravidram :swelling and softening of gingivitis
Systemic…cont’d
2312/2/2019
Due to ⇧ intragastric pressure.
normal 48 hours post delivery

24. Stomach
 Heartburn (pyrosis) due to relaxation of the cardiac sphincter and
may increase nausea and regurgitation
 Slow gastric emptization
 Delayed gastric acid secretion rate /hydrochloric acid and pepsin
 Increased gastric mucus secretion.
 Why?
Systemic…cont’d
2412/2/2019

25. Intestine
 Peristalsis is slowed b/se of the production of progesterone, which
↓ses tone and mobility of smooth muscles
 This slowing enhances the absorption of nutrients eg. Fe
 Movement through the large intestines is also slowed due to an
increase in water consumption from this area and ⇧ses the chance for
constipation
Systemic…cont’d
2512/2/2019

26. Colon
 Constipation
 Hemorrhoids
Gallbladder
 Increase residual volume
 Increased biliary cholesterol saturation i.e. stone formation
Liver
 Increased concentration of phosphate and cholesterol
Systemic…cont’d
2612/2/2019

27. 8. Hematology
 Increased:
WBCs
RBCs and
Coagulation
 Decrease platelets
Systemic…cont’d
2712/2/2019

28. 9. Changes of selected glands of the endocrine system
 Increased:
Estrogen
Progesterone
Melenocyt
Oxytocin : by posterior pituitary
 Prolactin: by anterior pituitary
Adrenal gland
Systemic…cont’d
2812/2/2019

29.  Thyroid gland :enlarged but euthyroid
 Parathyroid Gland:
 Increases in size slightly
 It meets the increased requirements for calcium needed for fetal growth
 Placenta increases:
 HPL, Estrogen , Progesterone those causes insulin resistance
 FSH and LH : decreases
 ACTH and TSH : not affected
Systemic…cont’d
2912/2/2019

30. 10. Immune system
 IgG
 IgA decrease up to 30wks ,then become normal
 IgM
11. Changes in body weight
 Normal weight gain is about 24 to 30 pounds during pregnancy
 Results from:
Fetus
Placenta
Ux
Breast
Fat
Blood
Extra cellular fluid
Systemic…cont’d
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