about physical changes of pregnancy

1. PHYSIOLOGICAL
CHANGES IN
PREGNANCY: PART -
1
PRESENTER – DR. KAJAL GUPTA
MODERATOR – DR. MAYURI AHUJA

2. INTRODUCTION
Physiological changes begin soon after fertilisation and continues throughout pregnancy.
Following changes will be discussed:
Reproductive tract
Breast
Skin
Metabolic changes

3. VULVA AND VAGINA
 increase in vascularity and hyperaemia in the skin and
muscles of the perineum and vulva
 Increased vascularity leads to violet discolouration of vagina
and cervix
 epithelial thickening, connective tissue loosening, and
smooth muscle cell hypertrophy.
 all women show greater hiatal distensibility of vagina to
facilitate delivery.

4. • Vaginal ph decreases during pregnancy (~3.5)
• due to increase doderlline bacteria more glycogen is
converted into lactic acid .

5. CERVIX
 About 1 month after
conception, the cervix begins to
soften and had bluish tone.
 increase vascularity edema and
collagen change
 hypertrophy and hyperplasia of
the cervical glands

6.  Rearrangement of collagen-rich tissue aids the cervix in retention
of the pregnancy and dilatation.
 Endocervical mucosal cells produce copious amounts of tenacious
mucus
 It obstruct the cervical canal to protect the uterine contents
against infection
 At labour onset, , this mucus plug is expelled, resulting in a bloody
show
CERVIX

7. SIGNS IN PREGNANCY
Chadwick’s Sign
A dark blue to purple –red congested
appearance of vaginal and cervical
mucosa
Hegar’s Sign
Occurs in first trimester
Softening of uterus at isthmus
Goodell’s sign
Softening of uterus after 6 weeks

9. CERVICAL RIPENING
 connective tissue remodelling
 lowers collagen and proteoglycan concentrations
raises water content
 result of progesterone

10. UTERUS
UTERINE ENLARGEMENT
 stretching ,hypertrophy and hyperplasia of muscle cells
 stimulated by estrogen and progesterone
it occurs maximum in fundus
Fibrous tissue accumulates
• MYOMETRIUM
muscle layer of uterus thicken and strengthen during first half of pregnancy
 Gradually becomes thin in second half.
By term, the myometrium is only 1 to 2cm thin.

11. UTERUS
NON PREGNANT
UTERUS
PREGNANT UTERUS
Muscular structure Almost solid Relatively thin walled
weight Approx. 70 grams Approx. 1100 grams at term
volume ≤ 10ml 5L at term (avg)

12. • By the end of 12 weeks, the enlarged
uterus extends out of the pelvis.
• It gradually increases in size reaching
xiphi-sternum at 38 weeks
• The longitudinal axis of the uterus
corresponds to the pelvic inlet axis.

13. BRAXTON HICKS CONTRACTIONS
 In second trimester, can be
detected by bimanual examination
 unpredictable and sporadic and
usually nonrhythmic
 may cause some discomfort and
account for false labour.
 Intrauterine pressure : 5-25mm of
Hg.

15. UTEROPLACENTAL BLOOD FLOW
• Placental perfusion depends on total uterine
blood flow (uterine, ovarian and collateral)
• Uteroplacental blood flow increase
progressively
• Approx. 450 mL/min in the mid trimester
• Nearly 500 to 750 mL/min at 36 weeks.
• Fall in vascular resistance accelerates the
flow velocity
• Shear stress in vessels lead to
circumferential vessel growth.
• Nitric oxide—a potent vasodilator has role

16. OVARIES AND FALLOPIAN TUBE
 Ovulation ceases during pregnancy
 maturation of new follicles is suspended.
 corpus luteum functions during the first 6 to 7 weeks of pregnancy
 diameter of the ovarian vascular pedicle increased from 0.9 cm to
approx. 2.6 cm at term..
 The fallopian tube musculature, myosalpinx, undergoes little
hypertrophy

17. BREAST
 Breast become tender in early pregnancy.
 From second month, the breasts grow in size.
 Colostrum- can be seen as early as 12weeks of pregnancy
 Colostrum is deficient in potassium, fat and carbohydrate.
 Colostrum is rich in immunoglobulin and vitamins.

18.  Hypertrophy and proliferation of
ducts due to estrogen
 increaseda lveoli due to estrogen
and progesterone.
 Hypertrophy of connective tissue
 Increased ducts due to effect of
estrogen.

19.  The nipples become
considerably larger, more
deeply pigmented
 Areolae become broader and
more deeply pigmented and
more erectile

20.  Scattered through areola, the
glands of Montgomery
 Hypertrophic sebaceous glands.
 Enlargement of these called
Montgomery tubercle

21. SKIN CHANGES
 STRIAE GRAVIDARUM
In mid pregnancy, reddish, slightly depressed streaks develop in the
abdominal skin and in the skin over the breasts and thighs.
 STRIAE ALBICANS
In multiparas, glistening, silvery lines ,representing previous stretch
marks.

22. .

23.  LINEA NIGRA
In the midline of the anterior
abdominal wall
Dark brown-black pigmentation the
Due to increased melanocyte
secreting hormone.

24.  Brownish patches of varying size appear on the face and neck,
giving rise to chloasma or melasma gravidarum—the mask of
pregnancy.
 Angiomas / vascular spiders, common on the face, neck, upper
chest, and arms.
 Minute, red skin papules with radicles branching out from a central
lesion.
 All the skin changes are due to increased estrogen except increase
basal body temperature which is due to progesterone.

26. METABOLIC CHANGES
Basal Metabolic Rate
 Increases by 20% by third trimester
30% in twins
 Total energy demand associated in pregnancy is 77000 kcal
 85, 285, and 475 kcal/d during the first, second, and third trimester,
respectively

27. • Pregnancy is an anabolic state.
• Total serum calcium decreases
• Foetus is dependent on mother for: glucose, thyroxine,
calcium
• Vit. D requirement during pregnancy: 10mcg(400IU)/day
• Calcium requirement in pregnancy: 1200mcg/day

29. WEIGHT GAIN
 weight gain of approx. 12.5 kg
mainly by -
 uterus and its contents
 breasts
 expanded blood and extravascular extracellular fluid
volumes.
 smaller fraction from accumulation of cellular water, fat, and
protein.

31. PROTEIN METABOLISM
• The products of conception, uterus and maternal blood are relatively
rich in protein
• placenta concentrates amino acids into the fetal circulation by facilitated
transport
• placenta also involved in protein synthesis, oxidation, and
transamination of some nonessential amino acids
• average requirements
• 1.22 g/kg/d of protein for early pregnancy
• 1.52 g/kg/d for late pregnancy.

32. WATER RETENTION
 Due to reset in osmotic threshold for thirst
 Vasopressin secretion
 Drop in plasma osmolarity of 10 mosm/kg.
 The amount of extra water that gets accumulated during
pregnancy (approx. 6.5 L)

33. CARBOHYDRATE
 mild fasting hypoglycaemia, postprandial hyperglycaemia, and hyperinsulinemia .
 peripheral insulin resistance, for supply of glucose to the fetus.
 insulin sensitivity in late normal pregnancy is 30 to 70 percent lower
 Insulin resistance is maximum between 24 to 28 weeks
 hormones such as progesterone, placentally derived growth hormone, prolactin,
human placental lactogen (HPL) and cortisol has role in this.
 Hepatic gluconeogenesis is augmented.
 Plasma concentrations of free fatty acids, triglycerides, and cholesterol are also
higher in the fasting state.

34. LIPID
 there is increase levels of lipid , lipoproteins and apolipoprotein in plasma
 increase insulin resistance due to estrogen.
 Triacylglycerol and cholesterol levels in very low-density lipoproteins (VLDLs),
low-density lipoproteins (LDLs), and high-density lipoproteins (HDLs) are
increased during the third trimester

35. ELECTROLYTES
 During normal pregnancy
1000 mEq of sodium
300 mEq of potassium
(nearly retained)
 serum concentrations are diminished slightly ( expanded plasma volume)
 Magnesium
both total and ionized magnesium concentrations are significantly lower
during normal pregnancy.

36. CALCIUM
 Total serum calcium levels, decrease during pregnancy.
 Serum ionized calcium level remains unchanged
 the fetal skeleton needs approximately 30 g of calcium (80% is
deposited in third trimester)
 demand is largely met by a doubling of maternal intestinal calcium
absorption mediated partly by 1,25-dihydroxyvitamin D3 and
adequate dietary intake.

37. IODINE
 Requirements increase during normal pregnancy
1.Greater thyroid hormone production for maternal euthyroidism
2.Transfer thyroid hormone to the fetus
3.Fetal iodine requirements , fetal thyroid hormone production
augmented renal clearance of iodine
4.Glomerular filtration rate increases by 30 to 50 percent.