Small for gestational age

Dr.V.RavimohanSpR

• Definition

• Implications

• Causes

• Diagnosis

• management

Definition

SGA refers to a fetus that has failed to achieve a specific biometric or estimated weight threshold by a specific gestational age.

10 th centile

Abdominal circumference

Estimated fetal weight

One of most frequently sited suboptimal care is the failure

to suspect growth restriction in a mother with a previous history

to detect to act on to monitor

Implications

• stillbirth

• birth hypoxia

• neonatal complications

• Neurodevelopment delay

• type 2 (non-insulin-dependent) diabetes and hypertension in adult life.

Small for gestational babies

Fetal growth restriction

30%

constituninal small babies

70%

constituninal small babies

Fetal growth restriction

Small for gestational babies

constitutional70%

Fetal growth restriction

30%constitutional

Fetal growth restriction

Ott Wj.The diagnosis of altered fetal growth.Obstet Gynecol Clin North Am 1988;15:237-63Ott Wj.The diagnosis of altered fetal growth.Obstet Gynecol Clin North Am 1988;15:237-63

population sensitivity specificity

SFH General 27% 88%

customised fundal chart

General 48%

ultrasound scan biometry(AC)

High risk 72.9–94.5% 50.6–83.8%

Improving sensitivity…

– Use customised ultrasound charts(maternal weight, maternal height, ethnic group and parity)

– Use growth velocity in addition to size

biometric testsbiometric tests biophysical testsbiophysical tests

designed to predict size fetal wellbeing

•abdominal palpation •symphyseal fundal height •ultrasound biometry•ultrasound estimated fetal weight

•Doppler•Amniotic fluid index•CTG

diagnosis of SGA more indicative of FGR than SGA

NEWT

slideshare.net

Management

• (I) aetiology(ex.chromosomal defects)

• (ii)arrange surveillance

• (iii) delivery-» when? » how? » where?

Causes of Growth restriction

54%

20%

12%

8%6%

Severe UP dysfuction

Chromosomal abnormality

Structural malformation

Congenital infection

miscellaneous

High risk pregnancy management options 2nd edition p300High risk pregnancy management options 2nd edition p300

 Chromosomal abnormalities

10 th Centile 7%

5thCentile 19%

Surveillance

• Umbilical artery doppler is the primary surveillance tool– frequency of monitoring in SGA fetuses

with normal Doppler need not generally be more than once every fortnight.

Doppler indices

S/D ratio Systolic peak velocity

diastolic peak velocity

Resistance index Systolic-end diastolic peak velocity

systolic peak velocity

Pulsatility index Systolic-end diastolic peak velocity

Mean systolic velocity

Doppler

Absent/Reverse EDFEDF present

Delay delivey till 37w*

>34 weeksdeliver

<34 weeks(i)Admission

(ii)Closed surveillance(iii)steroids

<34 weeks with RED/AED

• Daily CTG/Biophysical profile/Venous doppler

• Consider delivery » Pathological CTG» Biophysical score <4» Reversal of doppler velocities in ductus venosus

during atrial contraction or umbilical vein pulsations

• My web site:www.mrcogexam.net

• MY blog :http://mrcogfacts.blogspot.com/

Survival by birth weight

Survival by gestation

Growth Restriction Intervention Trial (GRIT)

• Hypothesis:early delivery,to pre-empt intrauterine hypoxia,would alter brain development compared with delaying delivery for as long as possible ,to gain maturity.

588 babies(fetal compromise

between 24-36 weeks)

Immediate delivery(296)

Delivery when obstetrician no longer uncertain

(292)

OR 1.1(0.7-1.8)

Im m ed ia te d e live ry 5 5(1 9 % ) D e la yed d e live ry 4 4 (1 6 % )

D e a th a n d se ve re d isa b ility a t 2 yrs

Conclusion

• The present study should discourage doctors who deliver fetuses (<30 weeks) before at which they delivery can be delayed no longer.

Mode of delivery

Indications for LSCS

(I)late decelerations in antenatal CTG

(II)Reversed End diastolic flow

(III)thick meconium during induction of labour

Clinical obstetrics and Gynaecology 40:4:1997;p822

Summary

• Definition

• Implications

• Causes

• Diagnosis

• management