Introduction To Obstetrics Flashcards
What are the 4 categories of maternal physiological changes?
- Physical growth
- Circulatory system
- Respiratory system
- Metabolism and endocrine
The uterus grows from ___ g in size to __kg in size during pregnancy
2g - 1kg
The uterus can hold ___ml of volume normally and up to _____ml of volume during pregnancy
10ml
5000ml
There is significant weight gain that pregnant women undergo. Where do these weight gains occur and approximately how much is gained for each
- blood volume, ECF, ICF : 3kg
- uterus : 1.4kg
- placenta : 1kg
- Fetal growth : about 3kg
- breast tissue : 1kg
- Fat and Protein: 12 kg
During pregnancy the mother undergoes circulatory system changes. What part of these changes cause an “Increase”?
Increase in
- blood volume
- venous distension
- RBC
- WBC
- clotting factors
Why does blood volume increase in pregnant women?
This is to accommodate the circulatory needs of the mother and fetus. It allows for perfusion of maternal organs and in preparation of blood loss during delivery
What percentage does blood volume increase during pregnancy?
40-50%
How much does venous distention increase during pregnancy and what complication risk does it run?
- 150%
- development of DVT and PE; especially under conditions like prolonged bed rest
What percentage does RBC count increase during pregnancy?
33%
Normal WBC count is _____ and increases to ______ during pregnancy
4,400 to 12,000 cells/ul
Blood pressure drops during which trimester of pregnancy and then normalizes back?
In the second trimester and normalizes in 3rd
Why does the heart size grow during pregnancy. And by how much does the heart grow?
- the heart grows to boost cardiac output by 40% to meet the increased metabolic demands
- the heart grows 10 - 15%
How much does the heart rate increase during pregnancy?
15 - 20 BPM
Why can ectopic beats and SVT appear during pregnancy?
It can be due to the increased CO and HR
Why might left axsis deviation occur during pregnancy?
Caused by the pressure exerted on the diaphragm by the growing uterus
How much of the bodies oxygen demand increases during pregnancy?
Increases by 20% and half of this demand is by the uterus
What respiratory adjustments are made to the nasal track during pregnancy and why?
- nasal stuffiness and increased mucous production
- due to enhanced vascularity in the mucous membranes and nasal passages which can lead to frequent nose bleeds
How does progesterone play a role in respiratory changes during pregnancy?
- It lowers the CO2 level threshold in the medulla
- leads to bronchodilation and reduced airway resistance
- increases Tidal volume and Minute ventilation by 50%
Pregnant women experience a decrease in partial pressure CO2 and Bicarbonate levels. This leads to what?
Respiratory alkalosis
What does the hormone relaxin do?
Leads to the relaxation of ligament usually around the pelvic area to facilitate childbirth and accommodate the expanding uterus
What changes occur in carbohydrate demand during pregnancy?
The demand for carbs increase to supply glucose to the fetus
How does pregnancy affect maternal insulin sensitivity?
Insulin sensitivity decreases due to pregnancy hormones, this is to ensure adequate glucose supply to the fetus and preventing maternal hypoglycaemia
How can changes in carbohydrate metabolism during pregnancy lead to gestational diabetes?
The decrease in insulin sensitivity during pregnancy can lead to gestation diabetes in women predisposed to glucose regulation issues
