- During pregnancy, the female body undergoes many physiological changes to support the growing fetus. These include changes in the genital organs, breasts, skin, weight gain, fluid balance, blood volume, cardiovascular and respiratory systems, metabolism, and hormones. The endocrine system works to regulate these changes through increased levels of progesterone, estrogen, cortisol and other hormones produced by the ovaries, placenta, and pituitary gland. These changes help create a favorable environment for the fetus to develop over the course of the pregnancy.

1. PHYSIOLOGICAL CHANGES
DURING PREGNANCY
PRESENTER: Dr. Tanya Das
MODERATOR: Dr. Junu Bajracharya

2. GENITAL ORGANS
• VULVA:
• VAGINA:
- Hypertrophied, oedematous, increased
vascularity
- Jacquemier’s sign
- Secretion – thin, copious and curdy white
- pH- 3.5-6
- Preponderance of navicular cells in cluster

3. • CERVIX:
- Goodell’s sign
- Hypertrophy and hyperplasia of cervical
glands
- Mucus plug formation
- Marked endocervical mucosa proliferation-
appears as cervical erosion
- Secretion is copious and tenacious-
physiological leucorrhoea of pregnancy

4. • ISTHMUS:
- Hypertrophy and elongation to about 3 times
original length
- Incorporated into uterine cavity beyond 12
weeks
- Sphincter action of circular muscles

5. • UTERUS:
ENLARGEMENT
-7.5cm to 35 cm; 60 grams to 1100 grams; 5-10 ml
to 5 litres
- Body of uterus- hypertrophy and hyperplasia of
muscles; stretching of muscle fibres
- Arrangement of muscle fibres
:outer longitudinal
: inner circular
: intermediate- interlacing network of muscles

7. VASCULARITY
- Uterine artery diameter doubles and blood flow
increases to 8 times at 20 weeks of pregnancy
- Vasodilatation due to estradiol and progesterone
SHAPE
- Pyriform shape in early months, globular at 12 weeks,
pyriform again by 28 weeks, spherical by 36th week
- Antiverted upto 8 weeks, erect afterwards
- Dextro-rotated uterus with levo-rotated cervix
CONTRACTIONS- Braxton- Hicks

8. • FALLOPIAN TUBE AND OVARY:
- Placed vertical by the side of the uterus
- Tubes become congested, muscles are
hypertrophied
- Epithelium flattened and pathches of decidual
reaction seen
- Corpus luteum maximum at 8th week, colloid
degeneration occurs at 12th week

9. BREAST
• Increased size and vascularity( hypertrophy
and proliferation of ducts and alveoli)
• Hypertrophy of connective tissue stroma
• Increased vascularity
• Increased pigmentation of the nipple and
areola
• Secondary areola appears
• Montgomery tubercles appear on the areola(
dilated sebaceous glands)
• Secretion(colostrum) can be squeezed out of
breast at about 12th week

11. CUTANEOUS CHANGES

12. WEIGHT GAIN
• Total weight gain in pregnancy- averages 11 kg
for a healthy women
• Mainly increases in 2nd trimester, 0.5kg/week
• Causes: growing fetus
:uterus
:accumuation of fat and protein
:increased blood volume
:increased extracellular fluid

14. New Recommendations for Total and Rate of Weight Gain
During Pregnancy, by Prepregnancy BMI(IOM guidelines)
Pre-Pregnancy BMI BMI(kg/m2)
(WHO)
Total weight gain
range (Ibs)
Mean range in
( Ibs/ week)
underweight <18.5 28-40(12.7-18.14kg) 1-1.3
Normal weight 18.5-24.9 25-35(11.3-15.8kg) 0.8-1
overweight 25.0-29.9 15-25(6.8-11.33kg) 0.5-0.7
Obese (includes all
classes)
>30.0 11-20(4.9-9.07kg) 0.4-0.6

15. BODY WATER METABOLISM
• Amount of water retained at term-6.5 ltrs
• Pregnancy- a state of hypervolemia
• Retention of Na, K, and water:
- Changes in osmoregulation
- Increased estrogen and progesterone
- Increased renin and angiotensin activity
- Increased aldosterone
- Control by AVP

16. HEMATOLOGICAL CHANGES
NON-
PREGNANT
PREGNANCY
NEAR TERM
TOTAL
INCREMENT
CHANGE
BLOOD
VOLUME(ml)
4000 5500 1500 +30-40%
PLASMA
VOLUME(ml)
2500 3750 1250 +40-50%
RED CELL
VOLUME(ml)
1400 1750 350 +20-30%
TOTAL Hb(gm) 475 560 85 +18-20%
HEMATOCRIT 38% 32% diminished

17. PARAMETERS NON-PREGNANT PREGNANCY
(near term)
CHANGE
Total Protein(gm) 180 230 Increased
Plasma protein
concentration
(gm/100ml)
7 6 Decreased
Albumin
(gm/100ml)
4.3 3 Decreased
Globulin
(gm/100ml)
2.7 3 Increased
Albumin:globulin 1.7:1 1:1 Decreased
Plasma Protein changes during pregnancy

18. LEUKOCYTES AND IMMUNE SYSTEM
• Decrease in humoral and cell-mediated
immunity to accommodate foreign semi
allogeneic fetus.
• Neutrophilic leucocytosis
• ESR increased

19. PARAMETERS NON-PREGNANT PREGNANCY(near
term)
CHANGE
Platelets 1,80,000 Static or 15%
reduction of count
Fibrinogen(mg%) 200-400 300-600 +50%
Fibrinolytic activity depressed
Clotting time unaffected
ESR 10 mm/hr 40 mm/hr Increased 4X
CHANGES IN BLOOD COAGULATION FACTORS

20. CARDIOVASCULAR SYSTEM
NON-PREGNANT PREGNANCY
(near term)
CHANGE
CARDIAC OUTPUT
(litre/min)
4.5 6.26 +40%
STROKE VOLUME
(ml)
65 75 +27%
HEART RATE
(per minute)
70 85 +17%
BLOOD PRESSURE Unaffected or mid
pregnancy drop of
diastolic pressure
by 5-10 mmHg
VENOUS PRESSURE 8-10cm 20cm +100%
COLLOID ONCOTIC
PRESSURE(mmHg)
20 18 -14%
SYSTEMIC
VASCULAR
RESISTANCE
-21%
HEMODYNAMIC CHANGES DURING PREGNANCY

23. ENDOCRINAL CHANGES
• PITUITARY :
- Anterior pituitary increases in size and activity
- Posterior pituitary releases oxytocin at the onset of
labour
• THYROID:
- Increases in size and activity: physiological goiter
- Most pregnant women are euthyroid
- Thyroid binding globulin concentrations double
- Total T3, T4 are increased( not free T3, T4)
• PARATHYROID:
- Increases in size and activity to regulate calcium
homeostasis

24. • ADRENALS:
- Increase in size and activity
- Total cortisol increased
• PLACENTAL HORMONES:
- Progesterone: produced by the corpus luteum,
levels rise steadily during pregnancy
- Oestrogens: ovary in early pregnancy, later
oetrone and oestradiol produced by placenta

25. METABOLIC CHANGES
• CARBOHYDRATE METABOLISM:
- Pregnancy is hyperlipidemic and glucosuric state
- Insulin secretion is increased in response to glucose
and amino-acids
- After mid-pregnancy, resistance to insulin develops
- Insulin resistance is endocrine driven, via increase in
cortisol and hPL
- Plasma glucose concentrations rise, maintained
between 4.5-5.5 mmol/L
- Plasma glucagon level remains unchanged
- Overall effect is fasting hypoglycemia and post
prandial hyperglycemia and hyperinsulinemia

26. NON-PREGNANT PREGNANCY
(near term)
CHANGE
TOTAL LIPID
(mg/100ml)
650 1000 +50%
LDL and cholesterol
(mg/100ml)
180 260 +40%
HDL
(mg/100ml)
60 70 +15%
TRIGLYCERIDES
(mg/100ml)
80 160 +50%
CHANGES IN LIPID METABOLISM

27. • PROTEIN METABOLISM:
- Positive nitrogen balance
- At term, fetus and placenta contain about 500
gm chiefly distributed in the uterus, breasts and
the maternal blood
- Blood urea level falls to 15-20 mg%
- Amino- acids transported across placenta to the
fetus

28. • IRON METABOLISM:
- Total iron requirement during pregnancy is
estimated approximately 1000mg
- Serum iron concentration falls, absorption from
gut and iron binding capacity increase

29. RESPIRATORY SYSTEM

30. NON-PREGNANT PREGNANCY
(NEAR TERM)
CHANGE
RESPIRATORY
RATE
15 15 Unaffected
VITAL CAPICITY 3200 3300 Unaffected
TIDAL
VOLUME(ml)
475 675 +40%
RESIDUAL
VOLUME( ml)
965 765 -20%
TOTAL LUNG
CAPICITY
5000 4750 -50%
CHANGES IN RESPIRATORY SYSTEM

32. ALIMENTARY SYSTEM
• Gums become congested and spongy and may
bleed to touch
• Muscle tone and motility is diminished
• Cardiac sphincter is relaxed and regurgitation of
acid gastric content into the oesophagus may
produce chemical esophagitis and heart burn
• Diminished gastric secretion and delayed
emptying time of the stomach

33. URINARY SYSTEM
• Kidneys : increase in size
: hydronephrosis
: effective renal plasma flow increased
• Ureter : atony of the ureteric muscles
: vesico-ureteric reflux increased
: leads to urinary stasis and pyelitis
: elongation and kinking of ureter
: outward displacement of ureter
• Bladder: congestion and hypertrophy of muscles
: bladder mucosa becomes oedematous

36. THANK YOU