SGA Flashcards
What are the major risk factors for SGA (OR>2.0)?
1.Maternal age >40yrs
2.Maternal SGA
3. Chtn
4. Dm w/ vascular disease
5. APL syndrome
6. Moderate to severe kidney disease
7. Prev sga baby
8. Prev SB
9. Prev unexplained preterm SB
10. Paternal SGA
11. Smoking >11cig/day
12. Cocaine
13. Daily vigorous exercise
- reassess risks at 20-24weeks:
14. PAPP-A <0.4MoM
15. Echogenic bowel
16. Poor weight gain
17. Unexplained APH
18. Severe PIH
19. Heavy bleeding
Need only one for surveiĺlance!
What are the minor risk factors for SGA (OR <1 to <2.0)?
- Maternal age 35 and above
- Nulliparity
- African-American/Indian/Asian ethnicity
- BMI <20 or >25
- IVF singleton pregnancy
- Pre-eclamsia
- Pregnancy interval <6mth or >60mths (5yrs)
- Heavy T1 bleeding
- Smoker 1- 10cig/day
- Moderate alcohol intake
- Maternal caffeine intake >300mg per day
- Low fruit intake prepregnancy
- Low socioeconomic status
- Unmarried
- Domestic abuse
- reassess risks at 20-24weeks:
16. Mild PIH
17. Placental abruption
18.
Need at least 3 for surveillance!
What is the surveillance for women with a major or 3 minor risk factors for SGA?
**1Major - serial efw and UmAD starting at 26-28 weeks
** 3/more Minor- UtAD screening at 20-24 weeks
If the UtAD is abnormal at 20-24 on dopper assessment. What next?
- compare to what would be done initially was normal?
Abnormal UtAD at 20-24 weeks —- do SEFIAL efw and UmAD at 26-28weeks.
If the UtAD was normal then do ONE scan for efw and UmAD in T3.
What is echogenic bowel associated with?
SGA
Fetal demise
A. How is SGA diagnosed?
B. How often are measurements made to assess for SGA?
A. <10th centile for EFW and AC.
- use of customized charts adjusted for maternal wt, ht, ethnicity and Parity improve prediction.
B. 2 measurements of EFW and AC must be AT LEAST 3 weeks apart to minimize false pos rates
T/F. Serial growth velocity measures are superior to a single measurement in estimating FGR and poor perinatal outcomes?
True. 2 readings AT LEAST 3wks apart reduces the false positive rates
What is the expected AC and EFW mean growth rates after 30 weeks?
10mm/14days - AC
200mg/14days - EFW
14 days as assessment are usually every 2 weeks!
An AC mean growth rate of ____indicates FGR?
<5mm/14days
T/F. Amniotic fluid volume useful to diagnose FGR?
False
T/F. The use of uterine a. doppler is limited to predict FGR?
True
How would you investigate a severely SGA fetus detected on anomaly scan?
- Detailed anatomy scan with Umbilical Artery Doppler assessment.
- Karyotyping if structural anomalies are detected before 23 weeks.
—- because chromosomal abnormalities are seen in up to 19% of SGA fetuses
—– most common chromosomal defect is triploidy fetuses before 26 weeks, and trisomy 18 in those after 26 weeks
What percentage of SGA occurs secondary to infections?
Which infections should be screened for?
5%
- cmv
- toxo
- syphilis & malaria in High-risk pops
How do you determine the mode of delivery for an SGA fetus?
SGA plus:
- UmAD AREDV - deliver by csection
- Normal UmAD - IOL
- Abnormal Umbilical a. PI but
PEDV - IOL
- IOL has an increased risk of csection. Monitor with continuous CTG monitoring from the ONSET of uterine contractions.
- Deliver in a unit with access to neonatologists/ paediatricians and a neonatal ICU
- Neonataologist present if extremely preterm or severe FGR.
What is the purpose of fetal surveillance?
To predict fetal academia, thereby allowing TIMELY delivery before 1) irreversible end organ damage and 2)intrauterine death.
What is the timing of delivery for an SGA fetus?
Delivery by 37 weeks (the latest in all scenarios!!!)
- Normal efw & UmAD = 37 weekss
—-deliver >34 weeks if:
——static growth over 3-4wks
——- MCA PI < 5th centile - PEDV with PI or R1 >2SDs = 37wks
——- deliver >34 wks if:
————-static growth over 3wks - AREDV = deliver BY 32 wks
— Consider delivery at 30-32 wks even if ductus venosusnis normal
—- RECOMMEND delivery <32wks if:
——— 1) abnormal ductus venosus doppler AND/OR 2) abnormal CTG
provided GA>24 & EFW>500g
In a preterm, SGA fetus, which doppler assessment should be used for surveillance and to time delivery? Why?
The ductus venous doppler (DtV)
DtV dopper has a moderate predictive value for acidaemia and adverse outcome.
What does a reduced MCA PI indicate?
It is an early sign of Fetal Hypoxia in SGA fetuses
- due to the brain sparing effect where chronic hypoxia - vasodilation & increased diastolic - decreased MCA doppler indices
Why is MCA not used to determine the time of delivery?
Because the MCA doppler has limited accuracy to predict:
-Acidaemia and
-Adverse outcomes
What’s the benefit of UmAD measurements? How often is surveillance?
They reduce perinatal morbidity and mortality in patients at high risk for SGA.
- UmAD surveillance is every 14 days once normal.
— if severe SGA, the more often surveillance may be warranted.
Which UmAD indices (PI, RI, systolic/diastolic ratio and diastolic average ratio) is best to predict adverse perinatal outcomes?
*pulsatility index (PI), resistance index (RI)
UmAD RI has the best discriminatory ability to predict a range of perinatal adverse outcomes.
How often is UmAD surveillance when PEDV or AREDV?
PEDV- twice weekly
AREDV - daily
