obg: The Physiology of Pregnancy (share)

The following hemodynamic changes are characteristic in pregnancy, except:

A) increase in cardiac output

B) decrease in blood pressure in the first half of pregnancy

C) increase in heart rate

D) increase in venous pressure in the lower limbs

E) increase in central venous pressure

E) increase in central venous pressure

EXPLANATION

Hemodynamic changes in pregnancy include increased cardiac output, decreased blood pressure in the first half of pregnancy, increased heart rate and increased venous pressure in the lower limbs. Pregnancy is not characterized by an increase in central venous pressure.

CTG alteration in vena cava inferior syndrome:

A) persistent tachycardia

B) acceleration

C) the fetal heart rate is unchanged

D) the fetal heart rate decelerates

E) reduced oscillation

D) the fetal heart rate decelerates

EXPLANATION

In vena cava inferior syndrome the placental circulation is decreased, therefore the fetal heart rate decelerates, bradycardia can be seen on CTG.

Physiological changes in pregnancy, except:

A) the pH and composition of the saliva changes

B) stomach and intestinal motility increase

C) pyelectasia, especially on the right side

D) serum levels of T3, T4 increase but TSH level is unchanged

E) the ligaments are loosened

B) stomach and intestinal motility increase

EXPLANATION

In pregnancy the composition and the pH of the saliva changes due to hormonal effects. The enlarged uterus compresses the ureters and as it leans towards the right side the compression and enlargment of the ureter is more expressed on the right. The retrograde urine stasis may cause pyelectasia. The pregnant uterus pushes the intestines upwards, and the motility of the intestinal tract decreases. In pregnancy, the levels of serum T3, T4 increase, TSH remains unchanged. The joints are loosened.

Vena cava inferior syndrome features:

A) headache

B) maternal blood pressure decreases

C) phosphene

D) vena cava inferior thrombosis and increased maternal blood pressure

B) maternal blood pressure decreases

EXPLANATION

In vena cava inferior syndrome when the pregnant woman lays back the uterus overlies and compresses the vena cava inferior. Due to the decline in venous backflow, a fast maternal blood pressure drop occurs, dizzyness, sweating and tachycardia may lead to collapse. The decrease in the placental circulation causes fetal bradycardia. Vena cava inferior syndrome is not characterized by headache, visual symptoms, vena cava inferior thrombosis or elevated blood pressure.

The following changes are characteristic in pregnancy, except:

A) acromegaloid symptoms

B) hyperpigmentation

C) increased lumbar lordosis

D) general vessel dilation

E) decrease in cardiac output

E) decrease in cardiac output

EXPLANATION

As a consequence of hormonal changes in pregnancy, acromegaloid symptoms, hyperpigmentation, increased lumbar lordosis and vesseldilation occur frequently. Cardiac output increases in healthy pregnancy.

The carbohydrate metabolism in pregnancy is characterized by:

A) higher fasting blood sugar levels

B) increased insulin resistance

C) lower fasting blood glucose levels

D) reduced insulin resistance

E) increased glucose absorption

B) increased insulin resistance

EXPLANATION

The carbohydrate metabolism of the pregnant woman is characterized by increased insulin resistance.

Required daily calcium intake in pregnancy:

A) 800 mg

B) 500-1000 mg

C) 1200 mg

D) 2000 mg

E) 3 g

C) 1200 mg

EXPLANATION

Daily calcium requirement in pregnancy is 1200 mg.

Daily iron requirements in pregnancy (based on RDA recommendations):

A) 30 mg

B) 100 mg

C) 5-10 mg

D) 300 mg

E) 500 mg

A) 30 mg

EXPLANATION

The daily iron requirement in pregnancy is 30 mg.

Which skin condition is characteristic for pregnancy?

A) depigmentation

B) erythema nodosum

C) lichenificatio

D) increased pigmentation

D) increased pigmentation

EXPLANATION

Characteristic skin change in pregnancy is the increased pigmentation. Especially in those areas that are predominantly pigmented: the vulva, skin under the navel and the nipples. The pigment spot around the eye and the cheekbones is chloasma gravidarum. The cause of pigmentation is the increased production of melatonin. Increased pigmentation will regress after birth.

Protein content of urine collected in 24 hours in normal pregnancy:

A) is abnormal only if it exceeds 500 mg / l

B) is acceptable only if less than 300 mg / l

C) not abnormal up to 1000 mg / l

D) is acceptable only under 150 mg / l

B) is acceptable only if less than 300 mg / l

EXPLANATION

In normal pregnancies, protein content of urine collected within 24 hours is below 300 mg.

Causes of physiological glucosuria in pregnancy:

1) increased mobilization of carbonhydrate storages

2) increased GFR

3) reduced insulin resistance

4) filtered glucose can not be reabsorbed in tubules

5) glucose excretion increases in tubules

A) 1st, 2nd and 3rd answers are correct

B) 1st, 3rd and 4th answers are correct

C) 1st, 4th and 5th answers are correct

D) 1st, 3rd and 5th answers are correct

E) 2nd and 4th answers are correct

F) 2nd, 3rd and 4th answers are correct

E) 2nd and 4th answers are correct

2) increased GFR

4) filtered glucose can not be reabsorbed in tubules

EXPLANATION

In pregnancy, the cause of physiological glucosuria is that glucose excreted via increased glomerular filtration cannot be reabsorbed in the tubules.

During pregnancy, the following characteristic physiological changes occur in the kidneys and the urinary tract:

1) the ureter tone decreases

2) the peristalsis of the ureter increases

3) pyelectasia

4) the GFR increases

5) the kidney’s ability to dilute the urine is significantly reduced

A) 1st, 2nd, 4th and 5th answers are correct

B) all of the answers are correct

C) 2nd and 4th answers are correct

D) 1st, 3rd and 4th answers are correct

E) 2nd, 4th and 5th answers are correct

D) 1st, 3rd and 4th answers are correct

1) the ureter tone decreases

3) pyelectasia

4) the GFR increases

EXPLANATION

In pregnancy the tone of the ureters decreases, pyelectasia develops and the GFR grows.

Cardiovascular changes in pregnancy:

1) increased heart rate

2) increased systolic volume

3) increase in blood pressure in the second half of pregnancy

4) increased cardiac output

5) increased venous pressure in the lower limbs

A) 1st, 2nd, 4th and 5th answers are correct

B) all of the answers are correct

C) 2nd, 3rd and 4th answers are correct

D) 3rd, 4th and 5th answers are correct

E) 4th and 5th answers are correct

B) all of the answers are correct

1) increased heart rate

2) increased systolic volume

3) increase in blood pressure in the second half of pregnancy

4) increased cardiac output

5) increased venous pressure in the lower limbs

EXPLANATION

In pregnancy the heart rate increases, the systolic output increases, blood pressure is elevated in the second half of pregnancy, the cardiac output increases and the venous pressure increases in the lower limbs.

Characteristic for vena cava inferior syndrome:

1) decrease in maternal blood pressure

2) acceleration of fetal heart rate

3) faintness of the pregnant woman

4) occurs when the pregnant lays on the back

5) increased maternal blood pressure

A) 1st, 2nd and 3rd answers are correct

B) 1st, 3rd and 4th answers are correct

C) 2nd, 3rd and 4th answers are correct

D) 2nd, 4th and 5th answers are correct

E) 3rd, 4th and 5th answers are correct

B) 1st, 3rd and 4th answers are correct

1) decrease in maternal blood pressure

3) faintness of the pregnant woman

4) occurs when the pregnant lays on the back

EXPLANATION

See 7.4. question.

In vena cava inferior syndrome when the pregnant woman lays back the uterus overlies and compresses the vena cava inferior. Due to the decline in venous backflow, a fast maternal blood pressure drop occurs, dizzyness, sweating and tachycardia may lead to collapse. The decrease in the placental circulation causes fetal bradycardia. Vena cava inferior syndrome is not characterized by headache, visual symptoms, vena cava inferior thrombosis or elevated blood pressure.

Select the direction in which physiological parameters change during pregnancy:

A) increases

B) decreases

C) unchanged

D) increases in the first half of pregnancy

E) decreases in the first half and increases in the second half of pregnancy

OBG - 7.19 - heart rate

OBG - 7.20 - systolic blood pressure

OBG - 7.21 - insulin resistance

OBG - 7.22 - diastolic blood pressure

OBG - 7.23 - GFR

OBG - 7.24 - risk of thrombosis

OBG - 7.19 - heart rate - A) increases

OBG - 7.20 - systolic blood pressure - E) decreases in the first half and increases in the second half of pregnancy

OBG - 7.21 - insulin resistance - A) increases

OBG - 7.22 - diastolic blood pressure - E) decreases in the first half and increases in the second half of pregnancy

OBG - 7.23 - GFR - A) increases

OBG - 7.24 - risk of thrombosis - A) increases

Choose the direction in which each laboratory parameter changes in normal pregnancy:

A) increases

B) decreases

C) unchanged

OBG - 7.25 - hemoglobin level

OBG - 7.26 - white blood cell count

OBG - 7.27 - erythrocyte sedimentation rate

OBG - 7.28 - serum iron levels

OBG - 7.29 - clotting time

OBG - 7.25 - hemoglobin level - B) decreases

OBG - 7.26 - white blood cell count - A) increases

OBG - 7.27 - erythrocyte sedimentation rate - A) increases

OBG - 7.28 - serum iron levels - B) decreases

OBG - 7.29 - clotting time - C) unchanged

In healthy pregnancies, elevated white blood cell counts are often observed because the lifetime of white blood cells increase in pregnancy.

A) both the statement and the explanation are true and a causal relationship exists between them;

B) both the statement and the explanation are true but there is no causal relationship between them;

C) the statement is true, but the explanation is false;

D) the statement is false, but the explanation itself is true

E) both the statement and the explanation are false

C) the statement is true, but the explanation is false;

EXPLANATION

The white blood cell count may be elevated in pregnancy, but the lifetime of white blood cells does not increase.

The occurrence of glycosuria is always abnormal in pregnancy because the higher amount of glucose eliminated due to the increased GFR cannot be reabsorbed in the tubules.

A) both the statement and the explanation are true and a causal relationship exists between them;

B) both the statement and the explanation are true but there is no causal relationship between them;

C) the statement is true, but the explanation is false;

D) the statement is false, but the explanation itself is true

E) both the statement and the explanation are false

D) the statement is false, but the explanation itself is true

EXPLANATION

Physiological glucosuria might be present in pregnancy, due to the fact that the glucose excreted via the increased GFR cannot be reabsorbed in the tubules.

Maternal blood pressure increases in the first half of pregnancy because the cardiac output is increased by nearly 20% at the end of the first trimester related to the pre-pregnancy value.

A) both the statement and the explanation are true and a causal relationship exists between them;

B) both the statement and the explanation are true but there is no causal relationship between them;

C) the statement is true, but the explanation is false;

D) the statement is false, but the explanation itself is true

E) both the statement and the explanation are false

D) the statement is false, but the explanation itself is true

EXPLANATION

In the first half of pregnancy blood pressure decreases, but the cardiac output is nearly 20% higher than pregestational values at the end of the first trimester.

The circadian rhythm of blood pressure often changes in pregnancy because when the pregnant woman lays back the uterus compresses the vena cava inferior and prevent the flow in the pelvic veins.

A) both the statement and the explanation are true and a causal relationship exists between them;

B) both the statement and the explanation are true but there is no causal relationship between them;

C) the statement is true, but the explanation is false;

D) the statement is false, but the explanation itself is true

E) both the statement and the explanation are false

D) the statement is false, but the explanation itself is true

EXPLANATION

The circadian rhythm of blood pressure does not change in pregnancy (except in preeclampsia). Laying back, the uterus may compress the vena cava inferior and thus inhibit the vena cava inferior flow (vena cava inferior syndrome).

The risk of thrombosis is increased in pregnancy because the coagulation time is elongated.

A) both the statement and the explanation are true and a causal relationship exists between them;

B) both the statement and the explanation are true but there is no causal relationship between them;

C) the statement is true, but the explanation is false;

D) the statement is false, but the explanation itself is true

E) both the statement and the explanation are false

C) the statement is true, but the explanation is false;

EXPLANATION

The risk of thrombosis is increased in pregnancy due to the slow venous flow in the lower limbs and not because of the decreased coagulation time.

Pyelectasia of the right kidney is common in pregnancy because the uterus leans to the right and compresses the ureter.

A) both the statement and the explanation are true and a causal relationship exists between them;

B) both the statement and the explanation are true but there is no causal relationship between them;

C) the statement is true, but the explanation is false;

D) the statement is false, but the explanation itself is true

E) both the statement and the explanation are false

A) both the statement and the explanation are true and a causal relationship exists between them;

EXPLANATION

Pyelectasia is more common on the right side because the uterus slightly leans to the right.

The metabolism increases in pregnancy because reduced insulin resistance characterizes pregnancy.

A) both the statement and the explanation are true and a causal relationship exists between them;

B) both the statement and the explanation are true but there is no causal relationship between them;

C) the statement is true, but the explanation is false;

D) the statement is false, but the explanation itself is true

E) both the statement and the explanation are false

C) the statement is true, but the explanation is false;

EXPLANATION

Metabolic rate increases in pregnancy due to increased oxygen demand of the mother and the fetus and the altered function of the thyroid gland. Insulin resistance increases during pregnancy.

Many pregnant women complain of heartburn because in pregnancy gastric tone reduction leads to gastric acid regurgitation in the lower esophagus and causes chemical oesophagitis.

A) both the statement and the explanation are true and a causal relationship exists between them;

B) both the statement and the explanation are true but there is no causal relationship between them;

C) the statement is true, but the explanation is false;

D) the statement is false, but the explanation itself is true

E) both the statement and the explanation are false

A) both the statement and the explanation are true and a causal relationship exists between them;

EXPLANATION

A common complaint of pregnant women is heartburn, occuring due to the regurgitation of gastric acid because of the reduced gastric tone, resulting in chemical oesophagitis in the lower part of the esophagus.

The metabolism increases in pregnancy because the thyroid function is increased and also the oxygen demand of the maternal and fetal tissues is elevated.

A) both the statement and the explanation are true and a causal relationship exists between them;

B) both the statement and the explanation are true but there is no causal relationship between them;

C) the statement is true, but the explanation is false;

D) the statement is false, but the explanation itself is true

E) both the statement and the explanation are false

A) both the statement and the explanation are true and a causal relationship exists between them;

EXPLANATION

See 7.38. question.

Metabolic rate increases in pregnancy due to increased oxygen demand of the mother and the fetus and the altered function of the thyroid gland. Insulin resistance increases during pregnancy.