Module 4 Second Trimester Unit A-D Flashcards
How would you determine an EDB and current gestational age for a patient who presents for initial prenatal care in the second trimester? 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?
If the patient has a sure LMP date, then we use the same decision making as the first trimester.
With an unsure LMP, the U/S is required for EDC
Which fetal structures are used for dating ultrasounds in the second trimester?
BPD = biparietal diameter
HC = head circumference
AC = abdominal circumference
FL = femur length
Why are earlier dating ultrasounds more accurate than later dating ultrasounds?
The later in pregnancy that a dating ultrasound is performed, the greater the amount of uncertainty and error inherent in the calculation of the EDB. This is because all conceptuses begin at the same size but fetal growth becomes more and more variable as pregnancy progresses.
How would you decide whether to change a due date at different gestational ages in the second trimester?
It is rare to need to change the dates in the second trimester. If the patient has a sure LMP and/or an early U/S. That EDB should be used. If the patient has a questionable LMP and/or no early U/S, then the date may need to be changed.
14-15 6/7 must be 7d+ diff
16-21 6/7 must be 10d+ diff
22-27 6/7 must be 14d+ diff
28+ must be 21d+ diff
Imagine a patient is unhappy with the EDB you have set. How will you respond?
The bottom line is that you should not change a due date unless it meets the guidelines but you will want to be supportive and kind, providing individualized and respectful education, and listening carefully to the patient’s concerns.
What do you expect for a second-trimester blood pressure compared with the person’s baseline: higher, lower, or unchanged? What is the physiologic reason?
The arteries continue to be relaxed and peripheral vascular resistance continues to be lower than nonpregnant people so decreased blood pressure is normal until about 32 weeks gestation. Thus throughout the second trimester, you should continue to expect blood pressure to be a bit lower than the person’s normal.
How will you assess maternal weight gain in the second trimester? What factors will you consider?
Refer to weight gain chart
Nausea and vomiting are often gone or greatly diminished, leading to improved appetite and a broader range of foods the person is interested in eating. In some people, this can cause a jump in weight, and in others, it can cause a leveling off as tolerance to more nutritional foods increases. Improved energy levels sometimes allow pregnant people to resume their physical activity regimen.
How will you convey your assessment of weight gain, using principles of respectful patient-centered care?
Pregnant individuals often report feeling shamed and scolded about weight gain. Clinicians have a responsibility to assess weight gain and provide information and counseling about the relationship between weight gain patterns and optimal perinatal outcomes. But shaming and scolding are not likely to be successful.
What elements of a urine dip will you assess? What are some common variations of normal you might see?
A little bit of protein apparent on a urine dip can be normal (trace or even 1+ in some situations). This can be due to the presence of vaginal secretions in the urine or just an isolated finding.
Glucose is unlikely to be a significant finding on a urine dip. Increased GFR leads to changes in renal tubular function and glucose reabsorption during pregnancy. These changes make glycosuria common during pregnancy with at least half of all pregnant people having detectable or even marked glycosuria. Importantly, glycosuria during pregnancy does not correlate with abnormal glucose tolerance or altered carbohydrate metabolism.
If the patient is still experiencing significant nausea and vomiting, it can be helpful to assess specific gravity and ketones. If the patient reports dysuria, urinary urgency, or frequency that seems different than pregnancy-related urinary symptoms, assessing for nitrites and leukocyte esterase on a urine dip might be useful in addition to sending a clean-catch urine for urinalysis and culture & sensitivity. Sometimes urine-dip leukocytes can indicate possible vaginitis based on the presence of vaginal secretions in the urine.
How do clinicians manage common discomforts in the second 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.)
See common discomforts document
Which labs will you order in the late second trimester? Why is each of them done at this point in pregnancy?
CBC or H/H: assess for anemia
GDM: test for GDM
repeat antibody for Rh Negative: determine need for referral to MFM
How will you interpret and follow up on those results? 2nd trimester H/H, GTT, Rh testing.
True Anemia H/H: <10.5/<32%
GDM: The positive test is >130, 135, OR 140 mg/dL
Indirect combs normal result=Negative
Who needs RhoGAM in the late second trimester and why?
Antepartum prophylaxis at 26 to 28 weeks of gestation
Antepartum fetal-maternal hemorrhage (suspected or proven)
Actual or threatened pregnancy loss at any stage of gestation
Ectopic pregnancy
After the birth of an Rh-positive baby
Why?: The manufacturer’s information states that Regular RhoGAM (300 µg) will protect against exposure to up to 15 mL of Rh-positive red blood cells. If there is an exposure of more than 15 mL of Rh-positive red blood cells, the patient will require multiple doses of RhoGAM.
What should you do if it is unclear whether a person needs RhoGAM? What is the routine dose for 26-28 weeks?
If there is any question about the possibility of fetal-maternal hemorrhage, it is generally preferred to give it.
Note: Some patients will not receive it because of religion or not wanting children in the future.
Dose: 300ug
Where is the uterine fundus usually found at each gestational week in the second trimester? What method will you use to measure it at each gestational week?
12: At or slightly above level of symphysis (Palpation in relation to symphysis)
14: Several fingerbreadths above the symphysis (Palpation in relation to symphysis)
16: Midway between symphysis and umbilicus (Palpation in relationship to symphysis and umbilicus)
20: At level of umbilicus (Palpation in relation to umbilicus)
22-28: GA cm from symphysis to fundus (Tape measure from symphysis to fundus)
