ANTEPARTUM/ROUTINE OBSTETRICS Flashcards
Know what is done at each prenatal visit in the course of pregnancy
When is a ‘New OB’/first prenantal visit conducted in gestational age?
10-12 wga
In a New OB visit, what do we do in order to confirm pregnancy dating?
Ultrasound
What routine labs are performed in a NOB visit?
CBC
RPR
HIV
Hb electrophoresis
VZV
Rubella
GC/CT
Urine Culture
Hep B, C
Blood typing
Rh Status
Ab Screening
Aneuploidy Screening
Carrier Screening
When should Rh status be established?
With the first prenatal visit labs
What major diseases do we screen for carrier screening and when?
At the first prenatal visit (10-12 wga), we screen for CF and SMA
When do we conduct aneuploidy screening for the baby?
First prenatal visit labs
What vaccines do we recommend for the first prenatal/OB visit?
Influenza and COVID Vaccines
What do we look at in the second prental exam at 15-20 wga?
- Update H&P and problem list as appropriate
- FHR
- Anatomy Scan (18-22 wga)
- MSAFP maternal screen for alpha feto protein
When do we conduct the first anatomical ultrasound?
18-22 wga
What are we screening for with MSAFP?
MATERNAL SERUM ALPHA-FETOPROTEIN (MSAFP) The MSAFP screens for “open neural tube” defects. Open spina bifida (or “open spine”) and anencephaly are examples of open neural tube defects.
What does elevated AFP in pregnancy often indicate?
Neural tube and abdominal wall defects
What does decreased AFP in pregnancy be indicative of?
Trisomy 21 or 18
What is discussed in a 24 week prenatal visit?
- Update H&P and problem list as appropriate
- Fundal Height
- Labor pain management/contraception counseling (do you want an epidural or spinal? Do you want an IUD or nexplanon?)
What is done at a 28 wga visit?
- Update H&P and problem list as appropriate
- Fundal Height
- TDAP vaccine
- Rhogam if Rh negative
- CBC and 1 hr glucose screening
When do we normally conduct the 1 hr glucose screening?
If no hx of DM or GDM, then we do it at the 28 wga visit
When do we give Rhogam?
We give rhogam to an Rh negative mother at 28 weeks and after labor (within 72 hrs) and whenever there is an opprotunity for maternal fetal blood interaction such as with an amniocentesis, c-section, trauma, etc.
What is conducted at a 36 wga visit?
- update h&P as necessary
- Fundal height
- Fetal Presentation
- GBS
- For high risk pts, repeat HIV, Hep B, GC/CT, RPR (syph)
- Discuss Delivery timing as indicated (induction of labor, cessarian, etc)
What is conducted at a 38-41 wga visit?
- Update H&P as needed
- Fundal Height
- s/c induction as needed
When would we conduct GDM early?
For patients with BMI >25 or >23 in asian amerians AND one of the following:
-Physical inactivity
-first degree relative with DM
-AA, Latino, Native, Asian American, Pacific Islander
-Previous infant >4000g
-Previous GDM
-HTN
-PCOS
-HDL <35 or TAGs >250 or hx of CVD
-A1c>5.7, impaired glucose tolerance, or impaired fasting glycose
What A1c do we use as the threshold for early glucose intolerance testing?
over and equal to 5.7
What is considered an abnormal 1 hr glucose test?
greater than 130-140, cut off varies by institution (130, 135, and 140 are often the cut offs)
What criteria do we look at for a 3 hr glucose test?
We use either the carpenter-coustan or NDDG which have diff thresholds (NDDG has overall higher thresholds for what they consider glucose intolerant)
What are some clinical features to look out for when you suspect a mother with GDM?
She may present asymptomatically, efema, polyhydramnios, large for gestational age fetus (>90th percentile)
What is our first line approach to a mother with nausea and vomitting in pregnancy?
- Switch prenatal vitamins to folic acid supplementation only
- Ginger capsule 250 mcg 4x qd
- Consider p acupressure with wrist bands
If first line approach to nausea and vommitting fails, what pharmalogical option will we consider next?
Vitamin B6 (pyridoxine) alone or in combination with Doxylamine
What pharmalogical options can we consider if first line and vitB6 fail for nausea and vommiting in pregnancy?
Dimenhydrinate, Diphenhydramine, proclorperazine, promethazine
At how many wga can you do cell free DNA screening?
Minimum of 9 weeks
Why would cell free dna and placental cells from CVS show variation from the fetus/be incorrect?
Mosaicism
When can a dx of intrauterine fetal demise be given?
after 20 weeks gestation
A patient with an IUFD after 20 wga has what managment options?
- Expectant Managment: most women (80%) will pass the fetus within 8 weeks of fetal demise, most likely 2 weeks
- Induction of labor if desired, vaginal misoprostil or oxytocin infusion
- Vacuum aspiration
Note the D and C is not indicated because D and C is for first trimester pregnancy loss
What are the major signs of DIC in pregnancy?
Prolong Prothrombin time, low platelets, elevated creatinin from acute renal injury
Look for:
-Platelet Count: LOW
-Fibrin Markers: elevated
-Prothrombin time: elevated/prolonged
-Fibrinogen Levels: variable
Recall that DIC is a condition characterized by systemic activation of the clotting cascade, platelet consumption, and subsequent exhaustion of clotting factors that leads to widespread thrombosis and hemorrhage. Often associated with trauma, shock, and sepsis.
DIC SCORE CALCULATOR:
https://qxmd.com/calculate/calculator_649/dic-score
In retention of IUFD over 2 weeks, what leads to DIC in some patients?
The systemic absorption of thromboplastin produced by the placenta and deceased fetus
What are our main causes of antepartum hemmorhage after 20 wga?
Common causes of antepartum hemorrhage are bloody show associated with labor, placenta previa, and placental abruption.
Rare causes include vasa previa and uterine rupture.
What are major risk factors for placental abruption?
-Previous abruption
-htn
-trauma
-smoking
-Cocaine
-PROM