| SYSTEM |
FUNCTION |
MECHANISM |
| Cardiovascular |
a) Higher peripheral oxygen demands (from
50 ml/min to 500 ml/min)
b) Cardiac Output increases by 40% (Heart
rate increases at the beginning up to 10 –
15 bpm and systolic volume by 10 to 12%)
c) Peripheral resistance decreases from
week 12 to week 24, becoming normal later
d)Blood returning to the heart is more
oxygenated
e) Resting respiratory rate is reduced whilst
vital capacity is preserved |
a) Oxygen uptake increases from 15 to 20 % during the 2nd half of pregnancy
This is caused by growing oxygen uptake from the uterus, placenta and fetus
b) Resting HR in the pregnant woman increases by the increase in gonadotropin
hormone, the lower activity of the parasympathetic system, and reduced
concentration of blood catecholamine
c) This is caused by vasodilation produced by hormones
d) Minute volume increases more than oxygen uptake
e) This is caused by a slight increase in inspiratory capacity |
Blood
|
a) Plasma volume increases gradually until the 32 weeks (30 to 60%),
b) Red blood cells number and size increase.
c) The veins increase their capacity and peripheral vascular resistance decreases. |
a) This causes a hemodilution of the blood causing the physiological anemia of
pregnancy
b) Produced by increased renal erythropoietin
c) Produced by effect of progesterone |
| Respiratory |
a) Resting hyperventilation to compensate alkalosis (increased ventilation from 6 L/min to 9 L/min). |
a) This is produced by the increment of the tidal volume, which removes more CO2 from blood, this raises PH.Also, it helped by chemoreceptors enhanced sensitivity to CO2 in order to prevent fetal ischemia and acidosis |
| Renal and urinary |
a) Dilated ureters and renal pelvis producing an increase of the dead space and a delay in the elimination of urine
b) Increased kidney size
c) Diastolic decreases 5 to 10 mmHg
d) Increased renal plasma flow, in the first quarter (600ml/min to 836ml/min). |
a) This is caused by aldosterone and estrogen release, which balance progesterone.
b) Caused by progesterone activity
c) Increased renin secretion and activation of the axis renin-angiotensin-aldosterone
d) The increased glomerular filtration. Later, it decreases |
| Gastro-intestinal |
a) Nausea, vomiting
b) Predisposition to tooth decay and gum hyperemia
c) Delay in time for gastric evacuation producing constipation
d) Pirosis |
a) Associated with hormone secretion (gonadotropins and estrogens)
b) Related to hormone concentration in saliva
c) The growing of the uterus, moves bowel and stomach.
d)Cardias sphincter relaxation causes the hydrochloric acid in the stomach to reflux into the esophagus |
Metabolic
|
a) Diabetogenic effect of pregnancy
b) Change in blood lipid profile
c) Increased resting metabolic rate |
a) This is due to some hormones like cortisol, estrogens and lactogen from
placenta can have blocking effects on insulin (insulin resistance)
b) Pancreas can naturally produce more insulin, causing gestational diabetes
c) Lipids increase from 600mg/ml to 900mg/ml Produced by the influence of
estrogens and cortisol
d) Caused by the increased demands from gestational state |
| Water Metabolism |
Increment in total body water |
a) Hydrostatic vessels pressure
b) Increase in lower limb blood flow return
c) Capillary permeability
d) Sodium retention |
Dermatological
|
a) Increased pigmentation
b) Possible appearance of stretch marks
c) Increased sweat secretion |
a) Caused by estrogen activity
b) Hormonal activity produces muscle distension and low ligament elasticity
c) Sweating glands tend to have a higher activity due to elevated hormonal secretion |
| Skeletal system |
a) Ligaments become more relaxed (Sacroiliac, Sacrococcygeal
and Pubic joints)
b) Increased lumbar dorsal curvature (lordosis)
c) Pain in zones around peripheral innervations
d) Frequent muscle cramps in the third term, especially in legs |
a) Caused by relaxin
b) Produced by the displacement of the center of mass
c) Produced by liquid retention and relaxation of ligaments by hormonal increase
d) Related to sodium depletion |
| Hormonal changes |
a) Human chorionic gonadotropin
b) Estrogens
c) Progesterone |
a) Human chorionic gonadotropin develops the placenta
b) Estrogens increase the size of the uterus and prepare milk ducts for breastfeeding
c) Progesterone retains pregnancy and develops the lobules of the breast |
| Body Weight |
Increase between 9 and 12 kgs
|
This is due to fetus growth; also mother gains fat mass, liquid, uterus blood volume, amniotic liquid, and placenta and breast tissue |
