Normal pregnancy and physiologic changes

Question 1

When measuring gravidity, does a multiple gestation count as 1 or 2?

Answer 1

One - counting the number of times pregnant

Question 2

When measuring gravidity would a hydatidiform molar pregnacy count?

Answer 2

Yes

Question 3

What is Goodell’s sign? When does it occur?

Answer 3

• Softening of the cervix

- 4-6 wks

Question 4

What is Chadwick’s sign?

Answer 4

• Blueish discolouration of the cervix and vagina

- Due to engorgement of pelvic vasculature

Question 5

What is Hegar’s sign? When does it occur?

Answer 5

• Softening of the cervical isthmus

- 6-8 weeks

Question 6

What breast changes occur in normal pregnancy?

Answer 6

• Engorgement
• Areolar darkening
• Prominent vascular patterns

Question 7

What is the B hCG rule of 10’s?

Answer 7

• 10 IU at missed period
• Week 10 is the peak at 100,000 IU
• 10,000 IU at term

Question 8

What produces B hCG? What is the function of B hCG?

Answer 8

• Produced by placental trophoblastic cells

- Function: maintains the corpus luteum during pregnancy

Question 9

When is hCG detectable in the serum? The urine?

Answer 9

1) Serum: 9 days post conception

2) Urine: 28 days after first day of LMP

Question 10

What is the expected doubling time for hCG? When does it peak?

Answer 10

• Doubles every 1-2 days
• Peaks at 8-10 weeks (100,000IU) and then plateaus until delivery
• Term level expected to be around 10,000 IU

Question 11

A patient comes in and has an hCG level less than expected for gestational age what is on your differential?

Answer 11

• Ectopic
• Abortion
• Inaccurate dating

Question 12

A patient comes in and has an hCG level higher than expected for gestational age what is on your differential?

Answer 12

• multiple gestation
• molar pregnancy
• trisomy 21
• inaccurate dates

Question 13

During which weeks is the 1st trimester?

Answer 13

0-14

Question 14

When is the second trimester?

Answer 14

week 14-28

Question 15

When is the 3rd trimester?

Answer 15

week 28-42

Question 16

What range is considered to be a normal term pregnancy?

Answer 16

37 weeks - 42 weeks

Question 17

What are some normal physiologic skin changes that occur during pregnancy? (4)

Answer 17

1) ^ pigmentation of perineum, areola, and under eyes on bridge of nose (chloasma)
2) Linea nigra (midline abdo pigmentation)
3) Spider angiomas, palmar erythema (due to ^ estrogen, like in liver disease)
4) Striae gravidarum (stretch marks)

Question 18

What are normal physiologic changes that occur to the cardiovascular system during pregnancy? (3)

Answer 18

1) Increased blood volume, CO, and HR
2) Decreased BP (due to v in PVR and v in venous return from enlarging uterus)
3) Increase in venous pressure (from uterus) ^ risk of varicose veins, hemorrhoids and leg edema

Question 19

What would you expect to see on the CBC of a pregnant women due to normal physiologic changes? (4)

Answer 19

1) Decrease in hemoglobin and hematocrit (dilution)
- > 33% hct (vs 37-47 non preg)
- > 110g/L (vs >120 in non-preg)

2) Increased WBC count (but with impaired fx)
- This is why autoimmune conditions improve in preg

3) Mild thrombocytopenia (no symptom)
- plt > 80k (typically 100-150k)
- normal for adults is > 150k

4) Hypercoagulable state
- Increased risk of DVT, PE
- v risk of bleeding at delivery

Question 20

What are some physiologic changes that occur to the respiratory system during pregnancy? (4)

Answer 20

1) ^ nasal congestion, epistaxis
2) ^ O2 requirement due to metabolic demand
3) Barrel chested (due to elevated diaphragm)
4) ^ minute ventilation, leads to v CO2 and mild respiratory alkalosis (this ^ diffusion of CO2 across placenta from baby to mom)

Question 21

What are the physiologic GI changes that occur during pregnancy? Which hormone causes most of these changes? (3)

Answer 21

1) GERD
- increased intra-abdo pressure
- progesterone decreases tone of sphincter and delays gastric emptying

2) Increased gallstones
- progesterone leading to biliary stasis

3) Constipation and hemorrhoids
- progesterone causing v GI motility

Question 22

Which physiologic GU changes occur in pregnancy? (5)

Answer 22

1) ^ urinary frequency due to ^ urine output
2) ^ incidence of UTI due to urinary stasis
3) Glycosuria can be physiologic in 3rd trimester (must test for GDM)

4) Dilation of ureters and renal pelvis (R>L)
- due to progesterone and uterine enlargement

5) decreased creatinine, uric acid, BUN
- ^ in GFR due to the increase in cardiac output

Question 23

Which two neurologic findings are more common during pregnancy?

Answer 23

1) carpal tunnel
- pressure on median nerve through carpal tunnel
- small space to start, becomes compressed with edema in pregnancy

2) Bell’s palsay
- CN VII palsay
- unknown etiology in pregnancy

Question 24

During pregnancy what results would you expect for:

1) Total thyroxine
2) Thyroxine binding globulin
3) Free thyroxine
4) TSH

Answer 24

1) total thyroxine: Elevated
2) TBG: increased
3) Free T4: normal
4) TSH: normal
* elevated total thyroxine and TBG counteract each other, so free (active) T4 and TSH are both unchanged

Question 25

What adrenal changes occur during pregnancy physiologically? (1)

Answer 25

• increased cortisol (total and free)

Question 26

How does calcium metabolism change in pregnancy? (3)

Answer 26

1) Decreased total maternal Ca2+
- due to decreased albumin

2) Free ionized Ca2+ (active) remains the same
- due to PTH increase
- causes ^ bone resorption and ^ gut absorption

3) Increased bone turnover without loss of bone density
- due to estrogen inhibition