Obstetrics Measurements

Question 0

Fetal age

Answer 0

Begins at the time of conception

Question 1

Gestational age

Answer 1

AKA menstrual age

Calculated from last normal menstrual period (40 weeks)

Question 2

Assessing gestational age

Answer 2

Sets delivery date

Schedule screening or invasive tests

Evaluate fetal growth

LMP is helpful but measurements is what we use

Question 3

Measurements

Answer 3

Take each measurement at least 3 times to reduce operator error

Question 4

Beta- hCG

Answer 4

Pregnancy hormone

keeps the uterus from having a period

for each week of pregnancy there is an expected value

Question 5

Gestational sac

Answer 5

Examine location of sac in the uterus to predict how likely it is for a miscarriage

Intrauterine gestational sac should be visualized by transvaginal US w/ beta-hCG values b/w 1000 and 2000 IU and abdominal exam 5500-6500 IU

Question 6

Visible ❤️activity

Answer 6

43 days (6.1w)

Question 7

Normal ❤️ rate

Answer 7

at 6 weeks 90-110 bpm

At 9: 140-170 bpm

At 8-9 weeks if no ❤️beat: no bleeding = 3% loss
Bleeding = 13% loss

At 5-8 weeks, bradycardia less than 90 bpm) is associated w/ a high risk of miscarriage