The document summarizes various metabolic changes that occur during pregnancy across several body systems. There is an increased total metabolism and basal metabolic rate to support the growth of the fetus. Protein metabolism shifts to an anabolic state to support increased protein needs. Carbohydrate metabolism involves increased insulin resistance and secretion to ensure glucose supply to the fetus. Fat storage increases by 3-4 kg to support energy needs. Iron metabolism is in an inevitable deficient state to meet the 1000mg of iron needs transferred to the fetus and placenta. Respiratory and renal systems expand to accommodate the growing uterus while hormonal changes like human chorionic gonadotropin and placental lactogen influence maternal physiology.

2. METABOLIC CHANGES
General Metabolic Changes
 Total metabolism is increased due to the needs of
the growing fetus and the uterus
 Basal metabolic rate is increased to the extent of
30% higher than that of the average for the non-
pregnant women.

3. PROTEIN METABOLISM
 Positive nitrogenous balance throughout
pregnancy i.e in ANABOLIC STATE.
 At term, the fetus and the placenta contain about
500 gm. of protein and the maternal gain is also
about 500 gm.
 As breakdown of amino acid to urea is suppressed,
the blood urea level falls to 15-20 mg%.

4. CARBOHYDRATE METABOLISM
 Insulin secretion is increased in response to
glucose and amino acids.
 Hyperplasia and hypertrophy of beta cells of pancreas.
 Plasma insulin level is increased due to a number of
anti insulin factors. These are estrogen,
progesterone, human placental, lactogen(hPL),
cortisol, prolactin, FFA, leptin, and TNF-alpha.
 Increased tissue resitance to insulin.
 Increased insulin level favours lipogenesis (fat
storage).This mechanism ensures continuously supply
of glucose to the fetus.

5.  Overall effects is maternal fasting hypoglycemia
(due to fetal consumption) and postprandial
hyperglycemia and hyperinsulinemia (due to
anti insulin factors).

7. FAT METABOLISM
 3-4 kg of fat is stored during pregnancy in abdominal
wall, breast, hips and thighs.
LIPID METABOLISM
 HDL level increases by 15%.
 LDL is utilized for placental steroid synthesis.
 Activity of lipoprotein lipase is increased.
 LEPTIN- a peptide hormone secreted by adipose tissue and
placenta regulates the body fat metabolism.

10. IRON METABOLISM
 Iron is absorbed in ferrous form from duodenum and
jejunum and is released into the circulation as
transferrin.
 10% of ingested iron is absorbed.
 Total iron requirement during pregnancy is estimated
approximately 1000mg.This is distributed in fetus and
placenta as 300mg, expanded red cell mass as 400mg
and obligatory loss of 200mg through normal routes.
 The iron in the fetus and placenta is permanently lost
during delivery(45mg/day) and rest is returned to the
store.

11.  There is a saving of 300 mg of iron due to amenorrhea for
10 months.
 In the second half of pregnancy, the daily requirement
increases about 6-7mg/day.
 The amount of iron absorbed from the diet and that
mobilized from the store are inadequate to meet the
demand. Serum ferritin level actually reflect the body iron
stores.
 In the absence of iron supplementation, there is drop in
haemoglobin, serum iron and serum ferritin concentration
at term pregnancy.
 Thus pregnancy is an inevitable iron deficiency state.

12.  Total body iron content average in normal adult
females is 2gm
 Iron requirement for normal pregnancy is 1 gm
 200 mg is excreted
 300 mg is transferred to fetus
 400 mg is need for mom
 Total volume of RBC inc is 350 ml
 1 ml of RBCs contains 1.1 mg of iron
 350 ml X 1.1 mg/ml = 400 mg
 Daily average is 6-7 mg/day
 Small intervals between pregnancies are most
concerning.

14. SYSTEMIC CHANGES
RESPIRATORY CHANGES
 Shape of the chest and the circumference increases in
pregnancy by 5-7 cm.
 Progressive increase in oxygen consumption, which is
caused by the increased metabolic needs of the mother and
fetus.
 The mucosa of the nasopharynx becomes hyperaemic and
oedematous and causes nasal stuffiness and rarely
epistaxis.
 A state of hyperventilation occurs during pregnancy
leading to increase tidal volume.
 The woman feels shortness of breath.

15. Respiratory ChangesRespiratory Changes
 Respiratory capacityRespiratory capacity
increasesincreases
 Shortness of breathShortness of breath
 Pulmonary reservePulmonary reserve
decreasesdecreases
 Increased risk ofIncreased risk of
muscle sorenessmuscle soreness
 Tendency toTendency to
hyperventilatehyperventilate
RESULTRESULT adjust the intensity level and duration of exerciseadjust the intensity level and duration of exercise

17.  ACID BASE BALANCE: Hyperventilation causes
changes in acid base balance.
 Pregnancy is in a state of respiratory alkalosis.

22. URINAY SYSTEM
 KIDNEY
 Dilatation of the ureter, renal pelvis and calyces. The
kidneys enlarge in length by 1 cm.
 Renal plasma flow is increased by 50-75%, maximum by
the 16 weeks and is maintained until 34 weeks. Thereafter it
falls by 25%.
 Glomerular filtration rate (GFR) is increased by 50% all
throughout the pregnancy
 URETER
 ureters become atonic due to high progesterone level.
 Dilatation of the ureter above the pelvic brim with stasis
is marked on the right side specially in primigravidae.

23. • BLADDER
• There is marked congestion with hypertrophy of the
muscles and elastic tissues of the wall.
• Increased frequency of micturition is noticed at 6-8 weeks
of pregnancy which subside after 12 weeks and In late
pregnancy, frequency of micturition once more reappears
due to pressure on the bladder as the presenting part
descends down the pelvis.
 Stress incontinence may observe in late pregnancy due
to urethral sphincter weakness

26. ALIMENTARY SYSTEM
 Gums become congested and spongy and may bleed to
touch.
 Muscle tone and motility of entire GIT are diminished.
 Risk of peptic ulcer disease is reduced.
 Atonicity of the gut leads to constipation
 LIVER AND GALL BLADDER
 Liver functions are depressed
 Marked atonicity of gall bladder (progesterone effect).
 High blood cholesterol level during pregnancy, favour
stone formation.

27. Difference in GIT in Pregnancy and
Non pregnant state

28. NERVOUS SYSTEM
 Temperamental changes are found during pregnancy and
in the puerperium
 Nausea, vomiting, mental irritability and sleeplessness are
probably due to some psychological background
 Postpartum blues, depression or psychosis may develop in
a susceptible individual
 Carpel tunnel syndrome may appear in the late
months of pregnancy due to the compression of the
median nerve underneath the flexor retinaculum.

30. CALCIUM METABOLISM AND
SKELETAL CHANGES
 Increased demand of Ca by the growing fetus to the
extent of 28 g.
 Daily requirement of calcium is about 1-1.5 g
 Ca absorption from intestine and kidneys are doubled
due to rise in level 1,25 dihydroxy cholecalciferol.
 Relaxation of pelvic ligaments and muscles occurs because
of the influence of estrogen and relaxtin reaches maximum
during last weeks of the pregnancy
 Increased lumber lordosis during later months of the
pregnancy due to enlarged uterus produces backache and
wadding gait

33. ENDOCRINE SYSTEM
Placental Hormones
Protein hormones
 Human chorionic gonadotrophin (HCG)
 Human placenta lactogen (HPL)
 Human chorionic thyrotrophin (HCT)
 Human chorionic corticotrophin (HCC)
 Pregnancy specific b-1 glycoprotein (PS b G)
Steroidal hormones
 Ostrogens – oestriol, oestradiol and oestrone
 Progesterone

35.  Human chorionic gonadotrophin (HCG)
 Secretion of progesterone by the corpus
luteum of pregnancy.
 HCG stimulates Leydig cells of the male fetus
to produce testosterone in conjunction with
fetal pituitary gonadotropins. It is thus
indirectly involved in the development of male
external genitalia.
Human Placental Lactogen (hPL)
Partial development of animal’s breast & lactation
Acts like GH; ↓insulin sensitivity & ↓glucose
utilization, & release free fats in mother to provide
more glucose to fetus. Potent angiogenic hormone.

36. Steroidal hormones
 Oestrogen
 Progesterone
 Together maintenance of pregnancy. Oestrogen causes
hypertrophy and hyperplasia of the uterine myometrium,
thereby increasing the accommodation capacity,
vascularity and blood flow of the uterus.
 Progesterone in conjunction with oestrogen stimulates
growth of the uterus
 Development and hypertrophy of the breasts. Hypertrophy
and proliferation of the ducts are due to oestrogen
 Both the steroids are required for the adaptation of the
maternal organ to the constantly increasing demands of
the growing fetus
 The steroids are involved in the complex pathway in
initiation of normal labour

37. Pituitary Hormones
 The secretion of prolactin, adrenocorticotrophic hormone,
thyrotrophic hormone and melanocyte-stimulating
hormone increases
 Follicle stimulating hormone and luteinzing hormone
secretion is greatly inhibited by placental progesterone and
estrogen.
 The effects of prolactin secretion are suppressed during
pregnancy
 Posterior pituitary gland releases oxytocin in low-frequency
pulses throughout pregnancy. At term the frequency of
pulses increases which stimulates uterine contractions

38. Thyroid Function
 Gland increases in size by about 13 percent due to
hyperplasia of glandular tissue and increased vascularity
 Increased uptake of iodine during pregnancy
 Pregnancy can give the impression of hyperthyroidism,
thyroid function is basically normal
 The basal metabolic rate is increased mainly because of
increased oxygen consumption by the fetus and the work of
the maternal heart and lungs