1. Bongkot Chakornbandit, MD. OB-GYN, HPC 10 Ubon Ratchathani
Low Birth Weight
Bongkot Chakornbandit, MD.
OB-GYN, HPC 10 Ubon Ratchathani

5. เป้าหมายงานอนามัยแม่และเด็กในแผนพัฒนาสาธารณสุข ฉบับที่ 11 (2555-60)
อัตราส่วนการตายของมารดา < 18:100,000 การเกิดมีชีพ
การติดเชื้อ HIV ในหญิงตั้งครรภ์ < 1 %
หญิงตั้งครรภ์มีภาวะโลหิตจางจากการขาดธาตุเหล็ก < 10 %
การขาดออกซิเจนในทารกแรกเกิด ไม่เกิน 30:1000 การเกิดมีชีพ
ทารกแรกเกิดน้ำหนักน้อยกว่า 2500 g < 7 %

6. สถานการณ์ LBW ภาพรวมเขตสุขภาพที่ 10
ปีงบประมาณ

7. UNICEF global databases, 2014

8. Low birth weight … problem of growth

9. Fetal growth 3 phases < 16 wks. : hyperplasia
16 – 32 wks. : cellular hyperplasia & hypertrophy
> 32 wks. : cellular hypertrophy
Fetal weight gain
15 wks. : 5 g/day
24 wks. : 15 – 20 g/day
34 wks. : 30 – 35 g/day

10. Fetal development
Maternal provision of substrate
Placental transfer
Fetal genome

11. Birth weight Vary with ethnicity, geographic region, genetic
Neonatal size
Small for gestational age (SGA)
Appropriate for gestational age (AGA)
Large for gestational age (LGA)

12. SGA Small for gestational age (SGA)
Neonatal weight < 10th percentile for their GA
Constitutional small
Congenital anomaly
Fetal (intrauterine) growth restriction (FGR / IUGR)
Symmetrical IUGR (type I)
Asymmetrical IUGR (type II)
Battaglia FC, Lubchenco LO. A practical classification of newborn infants by weight and gestational age. J Pediatr. 1967;71(2):

13. Definition WHO Birth weight < 2,500 g (5.5 pound) Die > 20 X
Both preterm birth / IUGR
increase neonatal morbidity & mortality
Inhibited growth & cognitive development
Chronic disease later in life

14. Factors for small infant
Same GA
Girls < boys
Firstborn infants < subsequent infants
Multiple pregnancy < singleton
Prepregnancy
Mother’s own fetal growth
Diet from birth to pregnancy
Body composition at conception

15. Smaller babies
Short stature
Living at high altitudes
Young women (teenage pregnancy)
Pregnancy
Mother’s nutrition & diet
Lifestyle (e.g., alcohol, tobacco or drug abuse)
Other exposures (e.g., malaria, HIV or syphilis)
Complications (e.g., hypertension)
Duration of pregnancy

16. Social
Deprived socio-economic conditions
Chronic poor nutrition and health problems
Physically demanding work during pregnancy

17. Low birth weight
Timing problem
Growth problem
Preterm birth
FGR

18. Preterm birth

19. Preterm birth Labor < 37 complete week Late PTB : GA > 34 wk.
Moderate PTB : GA wk.
Very PTB : GA 28 – 32 wk.
Extremely PTB : GA < 28 wk.

21. 40 – 45 % Preterm labor
30 – 35 % PPROM
30 – 35 % Medically indicated
Multifetal gestation

22. Cause of PTB Previous preterm birth Serious maternal disease Infection
Uterine problems / overdistension
Cervical problem
Placental abnormality
Other factors : smoking, drug abuse, teenage pregnancy, malnutrition, anemia

23. Prediction Cervical length (CL) Fetal fibronectin (fFN) Other
Risk scoring system
Cervical dilatation
Home uterine-activity monitoring

24. Prediction Cervical length (CL) Fetal fibronectin (fFN) Other
Risk scoring system
Cervical dilatation
Home uterine-activity monitoring

25. Cervical length (CL) TVS 16-24 wk./ early 3rd trimester
High risk for preterm
CL < 2 cm.
CL < 2.5 cm. with Hx PTB
CL > 3 cm.  low risk for PTB

27. Fetal fibronectin (fFN)
Glycoprotein in cervicovaginal secretion
Intercellular adhesion to uterine desidual
> 50 ng/ml  high risk for PTB
Contamination by maternal blood & AF

29. Prevention Identify high risk for preterm birth
Reduction teenage pregnancy
Avoid risk factors
Diminish correctable cause
Treat infection
Progesterone
17-hydroxyprogesterone caproate 250 mg. IM weekly (GA wk.)
Micronized progesterone Vg capsule mg nightly (GA wk.)
Cervical cerclage

31. Management Stop labor / Tocolysis Corticosteroid (GA < 32 – 34 wk.)
Antibiotic (PPROM)
Intrauterine transfer
Intrapartum & neonatal care

32. Growth restriction

33. IUGR Fetal weight < 10th percentile for their gestational age
25 – 60% (SGA < 10th) no pathologically growth restrict (consider ethnic, parity, wt. & ht.)
Other definition : wt. < 5th percentile.
Gynecologists ACoOa. ACOG Practice bulletin no. 134: fetal growth restriction. Obstet Gynecol. 2013;121(5):

36. Risk factor & Etiology

38. Maternal effect Increase cesarean section rate Child rearing problem
Mental effect

39. Fetal effect Hypoglycemia Hypocalcemia Polycythemia Hyperbilirubinemia
Meconium aspiration syndrome
Sepsis / infection
Asphyxia
Perinatal death

40. Long term sequelae Increase risk for
Cardiac structural change & dysfunction
Coronary heart disease
Artherosclerosis
Type II DM
Hypertension
Chronic kidney disease

41. Diagnosis
Risk scoring system PE
Body weight
Fundal height
Ultrasound

42. Weight Gain in 2nd & 3rd Trimesters (kg/wk)
Maternal body weight
Prepregnancy BMI
(kg/m2)
Category
Total Weight Gain
Weight Gain in 2nd & 3rd Trimesters (kg/wk)
< 18.5
underweight
12.5 – 18 kg
0.45 – 0.6
Normal weight
  kg
0.36 – 0.45
Overweight kg
0.22 – 0.3
> 30
Obesity
5 - 9 kg

43. Uterine fundal height
Simple
Safe
Inexpensive
Accurate screening method
Jimenez,et al. : GA wks.  GA cm.
Sensitivity < 35%, Specificity > 90%

44. Ultrasound Estimated fetal weight < 10th percentile
AC (Abdominal circumference)
< -2SD
HC/AC ratio

45. Amniotic fluid index
Placental grading
Doppler velocimetry
Brain sparing effect (MCA)
End-diastolic velocity in umbilical artery
Serial ultrasound follow growth velocity

46. Umbilical artery Doppler study

47. Prevention
Depend on cause of IUGR
Pre-gestational status
Nutritional status
Antenatal care / problems
Placental abnormality

48. Pre-gestational status
Improve BMI / pre-pregnancy maternal weight
Improve nutrition in reproductive age group
Prevention of teenage pregnancy
Cessation of drug use
Control underlying disease (DM, HT, CRF, APS)
Prevention anemia
Infection screening & Tx

49. Nutritional status Awareness case Age < 16 yr.
Low socioeconomic status
G 3 within 2 yr.
Eating limitation
Smoking / drinking / drug use
Low BMI (< 18 kg/m2)
Anemia
Weight gain in 2nd & 3rd trimester < 1 kg/mo. (2 lb/mo.)

50. Calories
additional 300 kcal/d
Total kcal/d in normal weight
Total pregnancy need 80,000 kcal
Protein
g/d
Carbohydrate
175 g/d
Iron
7 mg/d (GI absorb 10%)
Total pregnancy need 1,000 mg.

52. Antenatal care / problem
Risk identification
Rest
Control pregnancy complication ; PIH, anemia
US if suspected

53. Intrauterine growth restriction
Awareness in high risk case
Carefully ANC
Ultrasound for structural anomaly screening & fetal growth evaluation (32-34 wk. / suspicious case)
Early detection
Antenatal surveillance
Timing delivery & decrease neonatal adverse outcome