Module 5 Third Trimester Unit A-D

Question 1

How would you determine an EDB and current gestational age for a patient who presents for initial prenatal care in the third trimester, or if you had no idea which trimester the person was in? What if the person was sure of their LMP? What if they had no idea about LMP? What other ways could you corroborate the EDB?

Answer 1

Careful history taking
-LMP / discuss cycle characteristics
-Dates of positive pregnancy tests
-Onset of pg symptoms / quickening

Fundal height can help support date information
Ideally, dating U/S to be done ASAP → limitations to accuracy this far along
Dates are known to imprecise but can guide what needs to be caught up upon & how to proceed with pregnancy testing/care going forward

Question 2

How would you decide whether to change a due date in the third trimester?

Answer 2

Difference between ultrasound and LMP must be greater than 21 days for 28 weeks and beyond

Question 3

Given normal pregnancy physiology, what should the clinician expect for blood pressures in the third trimester?

Answer 3

Should return to pre-pregnancy level

Question 4

How does maternal position affect blood pressure in the third trimester?

Answer 4

-Lying on left side can reduce in, crossing legs, etc.
-Proper position: pt should have arm at heart level & not talk during measurement
-Lying on back: pg uterus presses on vena cava → can result in hypotensive syndrome, dizziness, tachycardia & nausea.

Question 5

What method should the clinician use to assess weight gain in the third trimester?

Answer 5

Look at total weight gain/trends and see if it tracks along what it should.

Question 6

How do clinicians manage common discomforts in the third trimester, including subjective and objective data collection, development of assessment/differential diagnoses, determination of normalcy, development of a plan, and patient education? (You should be able to navigate that process for each of the common discomforts listed below.)

Answer 6

Supine hypotension
Dependent edema
Leg cramps (including differentiating from DVTs)
Shortness of breath
Urinary frequency, nocturia, incontinence
Carpal tunnel
Back and pelvic pain
Varicosities
Insomnia/restless leg syndrome

Question 7

Which STI screening tests are repeated in the third trimester and in which patients?

Answer 7

HIV: high risk
Syphilis: high risk, positive 1st trim., high local cases, no hx of testing
Gonorrhea: continued high risk
Chlamydia: <25 or high risk
HBV: high risk or symptoms

Question 8

Who should be screened for GBS with a vaginal/rectal swab in late pregnancy and what is the acceptable gestational age range for screening?

Answer 8

36-37.6 for those who have not had baby sick with GBS infection in the past or positive urine at any point in the pregnancy..

Question 9

Who should NOT be screened for GBS with a vaginal/rectal swab in late pregnancy?

Answer 9

Those who had positive urine at any point.
Those who have had a previous baby that has contracted a GBS infection.

Question 10

What is the difference between fetal movement counting and fetal movement awareness? What is the evidence for each?

Answer 10

Counting is instructing the patient to focus and count (usually up to 10) the movements they are feeling. This can be time-consuming and has no evidence that it reduces IUFD.

Awareness is just general awareness that most patients will have. Awareness of normal awake times, and normal sensation is a good indicator of baby’s health.

Question 11

How should clinicians instruct patients if they choose to encourage formal fetal movement counting? How should clinicians instruct patients about fetal movement awareness?

Answer 11

Pick a time that is when baby is usually active. Count kicks and how long it takes to get to 10 kicks.

Be aware of when baby is normally active, if feeling like it is less, do kick counts and call provider.

Question 12

What is the normal range of fundal height in relation to gestational age in the third trimester?

Answer 12

Is still technically +/- 2cm but fetal position, dropping into the pelvis, etc can alter.
Concerning: Oligo, IUGR, etc. SO have a low threshold.

Question 13

What are the factors in the third trimester that can affect fundal height assessments?

Answer 13

Concerning: Oligo, IUGR, etc. SO have a low threshold.
Engagement can also cause a lower fundal height in third trimester

Question 14

What should a clinician include in a response to a third trimester patient who asks how big their baby is?

Answer 14

They are rough estimates, with the margin of error about the same for each.

Question 15

What are the steps in Leopold’s Maneuvers? What question(s) is each maneuver designed to answer?

Answer 15

1st-Fundus (head=round/hard and independent from body; butt=moves with body, small and firm)
2-sides (smooth is back)
3-C grip
4-Flexion/extension

Question 16

What are other clinical indicators of fetal presentation, aside from Leopold’s Maneuvers?

Answer 16

Location of fetal heart rate (want to be below umbilicis)
Where mom feels kicks (want to be up by fundus)
Have the felt any large, summersault type movements lately?

Question 17

What is the normal range for fetal heart rate in the third trimester?

Answer 17

110-160

Question 18

Why and how will you differentiate maternal from fetal heart rates?

Answer 18

Sound, and how low they are. Should always verify
palpate MHR

Question 19

How is a nonstress test conducted? How will you interpret it? What is the follow-up for a nonstress test that is not reactive for 20 minutes? For 40 minutes?

Answer 19

EFM and need two 15x15 accelerations within 20 min.
If they are not reactive within 20 min, you can extend monitoring to 40 min.
After 40 min if still non-reactive, BPP is performed.

Question 20

Why do we assess amniotic fluid volume? What are the ways we assess it? What are normal amniotic fluid volume results?

Answer 20

Ultrasound by max vertical pocket or AFI. This is part of a BPP.
Single deepest pocket vertical depth of 2.1-8 cm
Amniotic fluid index of 5-25 cm

Question 21

What criteria are included in a biophysical profile? What are the criteria for scoring each?

Answer 21

Movements: 3+ in 30 min
Breathing: 1+ lasting 30 seconds+
fluid level: Single deep pocket > 2cm
Tone: 1+ flexion/extenion of limbs or opening/closing hand
NST (optional): reactive

Question 22

Which BPP scores are considered reassuring? Which require collaboration or follow-up?

Answer 22

Reassuring
10/10 (score of 2 for all 5 elements above)
8/10 with normal fluid (score of 2 for amniotic fluid, 2 for all other elements with the exception of a single element). This is commonly seen when the NST is non-reactive but all other elements earn a score of 2.
8/8 without NST (if the NST is omitted which can be done in some situations)

Non-Reassuring:
Any BPP in which the amniotic fluid is abnormal
6/10 with normal fluid (score of 2 for amniotic fluid but 2 other elements are inadequate). This is commonly seen when the NST is non-reactive and the fetus does not fully meet the gross movement or tone requirements.
4/10 or less

Question 23

Why is amniotic fluid assessment so crucial as a scoring component in a BPP?

Answer 23

It indicates that the fetus is experiencing hypoxia and thus shunting the blood away from the kidneys -> causes less urine output aka amniotic fluid.

Question 24

What is a modified BPP and which outcomes require collaboration or follow-up?

Answer 24

NST + amniotic fluid level.
If amniotic fluid level is low, immediate follow up.
If NST is non-reactive, we would usually do full BPP.

Question 25

What is a contraction stress test and when might it be used?

Answer 25

Can be done with pitocin or nipple stimulation. Want to see how the bbay responds to contractions. If they are having decelerations with contractions, this is a positive/non reassuring CST.

Question 26

What is Doppler flow ultrasonography and when might it be used?

Answer 26

Doppler flow ultrasonography evaluates blood flow through specific vessels for indications of compromise.
This type of testing is most often used to optimize the timing of birth of fetuses in women who develop preeclampsia prior to 34 weeks EGA or those who are preterm and have suspected or confirmed FGR and are at high risk for intrauterine demise secondary to asphyxia

Question 27

What is the recommendation for influenza and Tdap vaccines in the third trimester?

Answer 27

TDAP between 28-36 weeks.
Flu prior to October.

Question 28

What are some ways that clinicians can respectfully and effectively discuss vaccine recommendations with patients who are vaccine-hesitant?

Answer 28

Non judgemental, shared decision making, be clear and unambiguous, motivational interviewing.

Question 29

When should patients return for each visit in the third trimester (assuming the traditional visit schedule)? What activities will take place at each visit?

Answer 29

Q2 weeks until 36 and then every week.
CBC, RPR and HBV (if high risk), HIV, glucose at 28 weeks
37 weeks GBS, repeat G&C (if high risk)
Assess fundal height, fetal heart rate, blood pressure and weight.

Question 30

What are the warning signs a patient should be advised to report during the third trimester?

Answer 30

Headache that is unrelieved by over-the-counter pain relievers or gets worse over time
Visual changes
Uterine cramping or more than 4-6 contractions per hour prior to 36 weeks
Vaginal bleeding
Leaking of fluid from the vagina
Decreased fetal movement

Question 31

What prenatal education topics are often discussed to help patients prepare for labor, birth, the postpartum period, and newborn care?

Answer 31

Planned place of birth (usually discussed earlier in pregnancy and finalized no later than the early third trimester)
Desires for specific labor and birth choices and experiences
Symptoms of labor onset and when to notify the clinician or birth location staff
Wide range of early labor experiences, including challenges in determining the onset of active labor
Self-care during early labor
Postpartum contraception plan
Infant feeding plan
Newborn care elements such as eye prophylaxis, vitamin K, vaccinations, circumcision, safe sleep, and car seats