Anatomical and physiological change in pregnancy

Dept. of Obs And Gyane ,Chittagong Medical college.
For 4th year MBBS Student

1. Anatomical & Physiological Anatomical & Physiological
changes in Pregnancychanges in Pregnancy
Dr.Fahmida Rashid Swati
Assistant Professor
Dept.of Obstetrics & gynaecology
Chittagong Medical College

3. •Pregnancy-
fertilization+
development of 1/>
embryo /fetus in a
woman's uterus.

4. Changes in Pregnancy
•1.Anatomical
•2.Physiological
•3.Biochemical
Genital
Organ
All System of
body
Maternal Adaptation
Increasing Demand of
growing fetus

5. Anatomical Change In Pregnancy

6. Changes in Genital organsChanges in Genital organs

7. •VULVA:
•Oedematous
↑ Vascularity → Superficial Varicocities

( Multiparae)
•Labia Minora
Pigmented
Hypertrophied

8. Vagina
•Wall –
Hypertrophied+Oedematous+↑Vascularity
→Bluish Colour( venous plexus)

•Secretion- Copious,thin,curdy white
•P
H -
Acidic(3.5-6)
Jacqemier,s Sign

9. Uterus
Pelvic organ <12wks
Abdominal >12 wks

10. Wight-60 gm
Size-7.5 cm
Cavity-5-10ml
Wight-900-1000gm(×20 )
Size-35 cm
Capacity-500-1000ml
Non pregnant
Pregnant

11. Change occurs in All 3 Parts of
uterus
•1.Body
•2.Isthmas
•3.Cervix

12. •Uterine expansion& increase weight

•Growing fetus
•↑ in connective tissue
•↑ size and no. of blood vessels
•↑Hypertrophy &hyperplasia of Muscle

13. Body -↑ Growth & enlarged by
Change in muscle -
1.Hypertrophy & hyperplasia (E+P)
2.Stretching of muscle fibre-
Elongate beyond 20 weeks( distension )
Wall - thinner , size- 1.5cm or less.
•Feeling of uterus-
Soft &elastic(non pregnant –Firm)
Fundus enlarge >Body

14. Arrangement of the muscle fibres
1)Outer- longitudinal
(2) Inner circular – sphincter like - around
internal os
(3) Intermediate – Thickest and strongest
Criss-cross fashion
Blood vessels run.
Figure of ‘8’ form.
.
living ligature

16. Pregnant uterus:
• Uterine = Ovarian Vessel
•Ut Vs>Ov Vs(non Pg)
•Spiral(High 20 wks)→Straight.
•Diameter –double
•Blood flow- ↑8 fold(20 wks)
{E+P}
•Vein-Dilated ,Valve less
•Lymphatic-Numerous channel
open up.
Vascular
System :

17. Shape
Pyriform
Early MONTH
Globular
12 weeks
Pyriform TO Ovoid

By 28 wks
Non pregnant:
Pyriform
Spherical
Beyond 36 wks

18. Position
 A/V positions exaggerated up to 8 weeks,lie
on bladder → erect.
Lateral Obliquity-
Uterus-Dextrorotation after 12 wks
{Due to rectosigmoid in lt. post.}
Cervix-Levorotation

19. Uterine Peritoneum-
Uterosacral ligameent & Base of Broad lig.
Raise upto Pelvic Bream
Lower lateral wall –Remain Uncovered

20. Contraction(Braxton-Hicks)
•Starts - early weeks ,not conscious about it
•Spontaneous, irregular, infrequent,
spasmodic ,painless without any
effect on dilatation of cervix.
•elicited by –BME/Rubbing
•Near term-Frequent,↑ intensity
•merge with labour contraction.

21. Endometrium(Decidua of Pregnancy)
•↑ structural & Secretory(P) after
implantation -- known as desidual reaction,

•Layers-
•A.Superficial compact layer-
implantation occur
•B.Intermediate spongy layer
•C.Thin basal layer.

22. Function:
a. good nidus for
implantation .
b.Supply nutrition .
c.Help in Deeper
penetration
d.Formation of basal
plate of placenta.

23. •Isthmus:
•1
st
trimester-hypertrophy,soft & elongated .
•>12 wks-Unfolds until it incorporated with
uterine cavity.
•As sphincter in early pregnancy.
•Incompetent--abortion( encirclage operation)

24. •Cervix:Bulky
•Stroma:H+ H,Fluid accumulate
•Vascularity –↑ – Bluish colour.
•Gland- H+H
•Cervix-Marked soft (Goodel,s Sign)-
-Diagnostic of pregnancy
- facilitate dilatation during laour.
•Epithelium-Marked proliferaation

25. Cervix
Secretion :
Copious & tenacious-
physiological leucorrhoea (P)
mucus plug(protective barrier ).
Directed –posterior until
engagement of head.

26. •Overy-
•Corpus luteum-maximum at
8wks(2.5cm),Cystic,Bright orange →yellow→
pale →colloid degeneration at 12 wk.
•Regressed – as hCG ↓.
Fallopian Tube:
length -↑,congested
Muscles - hypertrophy

27. •Corpus luteum
•Secrete E & P ,
• maintain environment for growing ovum .
formation and maintenance of decidua
Inhibit ripening of the follicles
•both ov. & Ut. cycle of normal menses remain
suspended.

28. •Size: ↑
( H+H & proliferation of duct&
Alveoli & connective tissue).
•Myoepithelial cell-prominent.
•Vascularity-↑
(bluish vein under skin)
•Stria-due to streching.
Change in Breast

29. Change in Breast
Nipple
Larger ,erectile,deeply Pigmented
Montogomery,s Tubercle
Hypertrophied Sebaceous Gland(5-15)
Secondary areola
Secretion:
Colostrum
(Sticky-at 12 wk,thick & yellow-
16 wk)

30. Changes in cutaneous system

31. Cutaneous -Pigmentation
more marked below umbilicus, breasts and
may , buttocks and thighs
Abdomen
Linea nigra : midline brownish black pigmented ,
xiphisternum to symphysis pubis
Straie graviderum : depressed
linear marks, varying length-breadth .

32. butterfly pigmentation
Face (cholasma gravidarum / pregnancy mask)
extreme form of pigmentation around the
cheek, forehead and around the eyes

33. Weight Gain
In early weeks -lose weight because of nausea
and vomiting
Wt GAIN = 17%
= 12 kg T
1
= 1-2 kg
T
2
= 5-6 kg
T
3
= 5-6 kg

34. Weight gain at term distribution :
Reproductive weight gain :
6 kg
Net maternal weight
gain :
6 kg
Fetus – 3.3 kg,
placenta – 0.6 kg and
liquor – 0.8 kg
uterus – 0.9 kg and
breast -0.4 kg,
accumulation of the fat and
protein – 3.5 kg
↑ blood volume – 1.3
kg
↑ ECF – 1.2 kg

36. Physiological change in pregnancy

37. Changes occur in pregnancy to
1. Support the foetus
2. Prepare mother for delivery
Changes are due to
1. Hormonal changes
2. Increasing size of uterus and
foetus
3. Anatomical changes

38. Systems affected
Body water metabolism
Hematological
Cardiovascular
Metabolic
Respiratory
Gastrointestinal
Hepatobiliary
Renal
Endocrine
CNS

39. Body water metabolism
•Water retained – 6.5 liters
•Fetus+placenta+Amniotic fluid=3.5 L
•Pregnancy –state of hypervolemia
•Due to Na+ retension.
•Resetting of osmotic thresholds for thirst and
ADH secretion.
•Cause-polyuria in early pregnancy

40. HEMATOLOGICAL CHANGES
Blood volume
 markedly raised.
starts from 6
th
week,
 maximum 40-50% above the nonpregnant
level at 30-32 weeks

41. Plasma Volume:
Starts to ↑ by 6 weeks
Rate of ↑ parallels to blood volume
↑ 50% of pre-pregnant level.
Total plasma volume ↑ 1.25 L

42. RBC And Haemoglobin :
RBC ↑ 20-30%.
↑ demand of O
2
transport .
 plasma 50% and RBC 20-30% - haemodilution
So , Hb% ↓ 2 gm.% .

43. Hematology & Coagulation
PARAMETER CHANGE
1. BV +45%
2. Plasma volume+ 55%
3. RBC volume +33%
4. Hemoglobin -17%
5. Hematocrit 35.5%

44. Leucocytes And Immune System
leukocytes depressed - increased susceptibility
of to infection
Total plasma protein- ↑( 180 gm to 230 gm).
But for haemodilution - conc.↓( 7 % to 6 gm.%)
Blood Coagulation Factor - hypercoagulable
Plasma fibrinogen (factor 1) ↑ from 12 wks.

45. Coagulation
Hypercoagulable, ↑ fibrinolysis, ↑platelet
turnover
↑FDP
↑Plasminogen
↓AT III
↑coagulation factors
↑fibrinopeptide A
TEG
↓PT/PTTK
BT
unaltered

46. CARDIOVASCULAR CHANGES
The Heart :
Muscle - hypertrophies → enlargement of the
heart.
Growing uterus push heart up and left .
 HR and SV ↑ as blood volume and oxygen
requirement ↑

47. Examination-
1.Apical impulse in 4
th
ICS & laterally
2.Loud S
1
3.A
2
P
2
changes less with respiration
4.Early mid-diastolic murmur at
left sternal border.
ECG –
1.Sinus tachycardia ( ↓PR & QT interval)
2.ST depression & T inversion in left prericardial
leads
3.Left axis deviation (false)

48. Cardiac Output : ↑ markedly.
lowest - sitting or supine position and
 highest - right / left lateral / knee chest
position.
Capacity of veins - ↑.
Arterial walls relax and dilate(P)

49. Blood Pressure
Mid-trimester- BP ↓; cause fainting.
In late pregnancy - 10% women “supine
hypotensive syndrome”
Pressure of gravid uterus compresses IVC - ↓
the venous return
CO ↓ 25-30% and the
BP ↓ 10-15 percent

50. Compression of aorta & IVC in supine & lateral tilt position
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52. Regional Distribution Of The Blood Flow
Uterine blood flow –
↑( 50 ml/Min to 750 ml/min)
Pulmonary blood flow
(N- 6000ml/min) -↑ by 2500 ml/min
Renal blood flow-
(normal 800 ml)- ↑by 400ml/M
Heat sensation, sweating or stuffy nose
due to ↑ blood flow

53. ECHO –
1. Enlargement of chambers
2. LVH
3. Annular dilatation of all valves except Aortic

(regurgitation)

Chest X Ray –
1. Apparent cardiomegaly
2. Straightening of left heart border

54. PARAMETER CHANGE
1.CO +40%
2. SV +30%
3. HR +15%
4. SBP No changeNo change
5. DBP -15%-15%
6. SVR -15%
7. Femoral venous P +15%
Note: fall in DBP while SBP is unaffected

55. Continued…

56. METABOLIC CHANGES
General Metabolic Changes
Total metabolism -↑( growing fetus and
uterus)
BMR +15% at term
Protein Metabolism
Positive nitrogenous balance
At term –fetus +placenta - 500 gm. of protein
and maternal gain -500 gm.

57. Carbohydrate Metabolism
Insulin secretion - ↑( glucose and amino
acids).
Hyperplasia and hypertrophy – β cells of
pancreas.

58. Estrogen, progesterone
Hpl, prolactin, contrainsulin factors
cortisol, FFA
hyperinsulinemia (resistance)

lipogenesis, hyperlipidemia, hyperketonemia

Fasting hypoglycemia (foetal consumption)
PP hyperglycemia& hyperinsulinemia
GLUCOSE METABOLISM ensure continuous

glucose supply to
foetus
4

59. Continued…
LIPID METABOLISM
↑HDL, LDL, TG
Hyperlipidemia of pregnancy is not
atherogenic.
3-4 kg fat stored (abdominal wall, breasts,
hips and thighs)

60. Iron Metabolism
Absorbed in ferrous form from duodenum and
jejunum and released into circulation as
transferrin
10 % of ingested iron – absorbed
Total iron requirement - approximately
1000mg
If no iron supplementation → ↓ Hb%, serum
iron and ferritin

61. SYSTEMIC CHANGES
Respiratory System
Chest shape and circumference - ↑ 5-7 cm
O
2
consumption +35% (↑needs of fetus,
uterus, placenta)
Mucosa of nasopharynx - hyperaemic and
oedematous
Hyperventilation - ↑ tidal volume
Shortness of breath
Respiratory alkalosis

63. Changes in Respiratory system
•Diaphragm - elevated and
compressed.
•Lungs - compressed due to
growing uterus.

64. Urinary System
•kidney
Dilatation of the ureter, renal pelvis and calyces.
 length ↑ 1 cm.
Renal plasma flow is ↑ 50-75%
GFR - ↑ by 50% .
↑ creatinine clearance →normal at 8-12 wk
postpartum
•Ureter
Atonic(P)
Dilatation of the ureter above the pelvic brim with
stasis is marked on the right side.

65. Renal
CHANGE CONSEQUENCE
1. Renal plasma flow↑(70%)
GFR ↑ +
Plasma expansion
Renal indices < normal
(creatinine ↓0.5-0.6)
BUN ↓ 8-9)
2. ↑GFR + ↓absorption
threshold
Mild glycosuria(1-10g/dl)
Proteinuria(<300mg/d)
3. Ureter & renal pelvis dilatePyelonephritis
Progesterone + estrogen → +RAAS → Na & H
2
O retention

66. •Bladder
↑ frequency at 6-8 weeks
 subside after 12 weeks
and
 In late pregnancy
-reappears due to pressure
of presenting part on the
bladder .
 Stress incontinence -late
pregnancy(urethral
sphincter weakness)

68. Alimentary System
Gums - congested and spongy ,bleed to touch
Peptic ulcer -reduced.
Atonicity of the gut - constipation
•Liver and gall bladder
Liver functions - depressed
High blood cholesterol level - favour stone
formation

69. Hepatobiliary system
Progesterone →↓ cholecystokinin→↓GB emptying
Altered bile composition
Serum bilirubin & liver enzymes
↑upto upper limit of normal range
Gall
stones

70. NERVOUS SYSTEM
Temperamental changes ,Nausea, vomiting,
mental irritability and sleeplessness
Postpartum blues, depression or psycosis - in
susceptible individual

71. CHANGES IN THE ENDOCRINE SYSTEM
Placental Hormones
Placenta produces - hormones
high E+P from placenta -- breast changes, skin
pigmentations and uterine enlargement in the
first trimester
hCG - immunologic pregnancy tests
hPL - stimulates the growth of the breasts

72. Pituitary Hormones
Prolactin, ACTH, Thyrotropic Hormone and
MSH -↑
FSH ,LH - greatly ↓ ( placental P+E).
Prolactin secretion - suppressed .
Posterior pituitary releases oxytocin in low-
frequency pulses , ↑ at term → stimulates
uterine contractions

73. THYROID
Thyromegaly due to ↑ placental HCG (↓TSH )
↑ T
3
+ T
4
↑TBG (estrogen)
Free T
3
/T
4
unchanged
Euthyroid

74. Changes in Musculo-skeletal system
Ligaments
•Placental production of the hormone relaxin
causes pelvic ligaments and the pubic symphysis
to relax, widen, and become more flexible.
•This increased motility eases birth passage, but
it may also result in a waddling gait during
pregnancy.

75. Postural changes:
During pregnancy, postural changes
occurred.
•These changes include
•forward head,
•rounded shoulders,
•increased lumbar lordosis- LBP 50%
•Center of gravity shift,
•hyperextended knees, and
•pronated feet.

76. •Muscular changes –
shortened hip flexors, lower back
musculature, and pectorals.
• Abdominal muscles, neck, and upper
back muscle groups elongate.

78. END