1. IN THE NAME OF ALLAH

2. Maternal Physiology

3. Maternal changes during pregnancy
The maternal system may produce a
series of changes in order to adapt to the
needing of fetal growth and development
influenced by placenta hormone and
neuro-endocrine

4. Uterus Changes of reproductive system
Body: become enlargement and soft
from 7×5 ×3cm pre-pregnancy to
35×25 ×22cm at term .
Volume of uterus cavity:
become enlargement from 10ml pre-pregnancy to 5000ml at term .

5. Weight: be increased from 70g pre- pregnancy
to 1100g at term .
Blood supply: blood flow increased
significantly .
upto ml/min,increased 4-6 times and
most of blood flow is transported to the
placenta(80-85%) .

6. Isthmus: be dilated and become soft from 1cm
pre-pregnancy a portion of the uterus
after 12 gestational weeks
Cervix: be soft and coloration or stain
secrete amount of mucus avoiding the
uterus cavity suffer from infection

7. Changes of ovary Stop ovulation .
Corpus luteum formation and maintains for
6-7 weeks .
The function of corpus luteum is
substituted by the placenta .
Corpus luteum atretic gradually after 3-4
months gestation.

9. Cardiovascular system
Heart:
move upward and left.
Cardiac Output
increase by 30%, reach to peak at 28nd – 32th week
Blood pressure
early or mid pregnancy Bp↓.late pregnancy Bp↑ .Supine hypotensive syndrome

10. Cardiac Output Maternal cardiac output is highest in which position?
lateral recumbent
Lowest?
Standing

11. Vascular Changes
SVR( Systemic vascular resistance) decreases until mid-pregnancy, then rises slightly but remains 20% below non-pregnant values
BP follows in parallel, especially DBP( mmHg)
SBP: 5-10 mmHg
diastolic blood pressure

12. Respiratory Physiology
changes in chest:
Transverse diameter increases 2 cm
Circumference increases 5-7 cm
Diaphragm rises 4 cm

13. The Respiratory system
Respiratory rate: no change
vital capacity: no change
Tidal volume: ↑ 40%
Functional residual capacity:↓
O2 consumption: ↑ 20%
Tidal volume

14. Respiratory Physiology
FEV1 (forced expiratory volume) is unchanged
TV increases about 40%; since RR is unchanged, that increases minute ventilation 40%
Increased MV leads to:
Increased alveolar oxygen
Slightly increased arterial oxygen ( )
Decreased alveolar and arterial CO2 (27-32)
maximum voluntary ventilation 
forced expiratory volume in

16. Physiologic changes in pregnant woman
Hematology
Blood volume
Increase by 30%-45% at 30nd –34th (peak)
Relatively diluted
Composition
Red cells
Hb:13→11g/dL, HCT:38%→ 31%.
White cells: slightly increase
Coagulating power of blood: ↑
Albumin: ↓,35 g/L

17. Hematologic Changes Blood Volume increases by? 40-50% Peaks at?
30-34 weeks
RBC Mass increases?
20% without iron supplementation
30% with iron supplementation

18. Hematologic Changes
What are the total iron demands for a normal term pregnancy in a woman without preexisting iron depletion?
1000 mg :
300 mg fetus and placenta
500 mg maternal red cell increase
200 mg compensate for normal daily losses

19. Hematologic Changes
Iron demands increase in later gestation (6-7 mg/day near term)
Iron supplementation is needed to avoid iron depletion during pregnancy

20. Hematologic Changes Mild decrease in mean platelet count
Increased platelet destruction
Diluted
Up to 8% will have gestational thrombocytopenia
Platelet count ,000/mm3
No increased bleeding complications
Return to normal after delivery

21. Hematologic Changes Mean WBC count increases
T helper 1 and natural killer cells decrease,
T helper 2 increase
Decreased concentrations of
IgG, IgM, IgA
1st trimester 8000 ( )
2nd and 3rd trimester 8500 ( )
In labor may rise to 26,000-30,000

22. Coagulation System (factors I, VII, VIII, IX, X).
Procoagulant factors increased
Natural inhibitors of coagulation decreased
Reduced plasminogen activator
Decreased fibrinolysis
Defense against puerperal hemorrhage
Increased risk of thromboembolism

23. 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
Pyrosis is common due to the reflux of secretions
Vascular swelling of the gums
Hemorrhoids due to elevated pressure in veins

24. GI Physiology Common symptoms: heartburn, increased appetite
Constipation may be increased
Overall inhibition of GI motility
Many physiologic changes attributed to progesterone
سوزش معده-یبوست

25. GI Physiology Esophagus no change in motility
Reduced Lower esophageal sphincter (LES )resting pressure (decreases with gestational age)
Lower esophageal sphincter pressure in patients with gastroesophageal reflux

26. GI Physiology
Stomach
Conflicting data on acid production, gastric emptying
increase in total emptying time

27. GI Physiology Intestines
decreased transit time shown in multiple studies, probably progesterone-mediated
Theoretical changes in absorption related to slower transit time and longer exposure of intestinal contents to the mucosa
could be beneficial - allow more time for absorption
could be detrimental - allow bacterial overgrowth

28. Hepatic Physiology Increased protein synthesis (estrogen effect)
increased clotting factors, binding globulins
hemodilution decreases albumin concentration
50% of normal pregnancies have dilated esophageal veins (portal-systemic shunt)
Hepatomegaly is abnormal; palmar erythema and spider veins common
متسع شده

29. The urinary system Kidney Renal plasma flow (RPF):↑35%
Glomerular filtration rate (GFR):↑ 50%
Ureter : diluted
Bladder : Frequent micturation

30. Thyroid Function in Pregnancy
Increased TIBG (via liver)
Increased total T4 and T3
free levels unchanged
HCG suppresses TSH