Low Birth Weight

PREMATURITY

&

LOW BIRTH WEIGHT

Dr.Sijal Fadhil Farhood FICMS-MSc Community Med.-MBChB

Preterm birth is the most common cause of death among infants worldwide. About 15 million babies are preterm each year (5% to 18% of all deliveries). In many countries rates of premature births have increased between the 1990s and 2016. Complications from preterm births resulted in 0.74 million deaths in 2013 down from 1.57 million in 1990. is the most common cause of death among infants worldwide.[1] About 15 million babies are preterm each year (5% to 18% of all deliveries). In many countries rates of premature births have increased between the 1990s and 2010s.[3] Complications from preterm births resulted in 0.74 million deaths in 2013 down from 1.57 million in 1990.[11] The chance of survival at fewer than 23 weeks is close to zero, while at 23 weeks it is 15%, 24 weeks 55% and 25 weeks about 80%.[12] The chances of survival without long term difficulties are lower.[13]th is the most common cause of death among infants worldwide.[1] About 15 million babies are preterm each year (5% to 18% of all deliveries). In many countries rates of premature births have increased between the 1990s and 2010s.[3] Complications from preterm births resulted in 0.74 million deaths in 2013 down from 1.57 million in 1990.[11] The chance of survival at fewer than 23 weeks is close to zero, while at 23 weeks it is 15%, 24 weeks 55% and 25 weeks about 80%.[12] The chances of survival without long term difficulties are lower.[13]

Definition :

What is preterm birth?
•

The delivery of a baby before 37 completed weeks' gestation.

Definition ii:
What is Birth Weight?

Birth weight is the body weight of a baby at its birth

Determinants of birth weight

There is a relation between birth weight and gestational age.
28 weeks : 900 g
36 weeks : 2750g

Definition ii:

What is Low Birth Weight?

Low birth weight

Either by a preterm birth (low gestational age at birth) or of the infant being small for gestational age (slow prenatal growth rate), or a combination of both.

Epidemiology of Low Birth Weight

In 1992 preterm live birth was lowered from 28 completed weeks' gestation to 24 weeks' gestation. This boundary varies internationally, however, from about 20 to 24 weeks.

Epidemiology of prematurity

Epidemiology

In Europe and many developed countries the preterm birth rate is generally 5–9%, and in the USA it has even risen to 12–13% in the last decades.


RATES IN IRAQ
In Iraq 15-16% of births are low birth weight just over one third is born premature



Several factors have contributed to the overall rise in the incidence of preterm birth. These factors include increasing rates of multiple births, greater use of assisted reproduction techniques, and more obstetric intervention.



Part of the apparent rise in the incidence of preterm birth, may reflect changes in clinical practice. Increasingly, ultrasonography rather than the last menstrual period date is used to estimate gestational age. The rise in incidence may also be caused by inconsistent classification of fetal loss, still birth, and early neonatal death.

Mortality and morbidity

Worldwide, prematurity accounts for 10% of neonatal mortality. In the U.S. where many infections and other causes of neonatal death have been markedly reduced, prematurity is the leading cause of neonatal mortality at 25%. Prematurely born infants are also at greater risk for having subsequent serious chronic health problems

TYPES OF DELIVERIES

1-Spontaneous preterm births : 40–45% preterm births that follow preterm labour
2- 25–30% are induced preterm births i.e premature rupture of membranes.
3- (30–35%) are preterm births via Cesarean section for obstetrical reasons; (i.e. infection, intrauterine growth retardation)




5% of preterm births occur at less than 28 weeks (extreme prematurity), 15% at 28–31 weeks (severe prematurity), 20% at 32–33 weeks (moderate prematurity), and 60–70% at 34–36 weeks (late preterm

Clinical impact of prematurity

Immediate:

1- Respiratory:

One of the main organs greatly affected by premature birth is the lungs. The lungs are one of the last organs to develop in the womb; because of this, premature babies typically spend the first days/weeks of their life on a ventilator suferring from such conditions as apnoea, RDS and asphyxia..

2- Neurological:

The other main system greatly affected by premature birth is the CNS… because of this, premature babies may suffer from intracranial heamorrhage.





3-Cardio vascular:
Bradycardia and hypotension
4-Haematological:
Anaemia and bleeding tendency
5-Gastrointestinal
6-Metabolic: Hypoglycaemia
7-Renal Reduced G Filtration
8-Temperature regulation
9-Immunity
10-Opthalmic

Clinical impact of prematurity

Late:
Chronic lung diseaes
CNS especially cerebral palsy
Poor growth

LIMIT OF VIABILITY

The earliest gestational age at which the infant has at least a 50% chance of survival is referred to as the limit of viability. As NICU care has improved over the last 40 years, viability has reduced to approximately 24 weeks, although rare survivors have been documented as early as 21 weeks. As risk of brain damage and developmental delay is significant at that threshold even if the infant survives, there are ethical controversies over the aggressiveness of the care rendered to such infants. The limit of viability has also become a factor in the abortion debate

PRETERM PATHWAYS

4 different pathways can result in preterm birth :


1-Precocious fetal endocrine activation.
2-Uterine over distension.
.3-Decidual bleeding
4- Intrauterine inflammation/infection.

Kangaroo Care

• Implications of low birth weight

perinatal & infant mortality

Increasing incidence globally

Human wastage

Emotional suffering

Very high cost of NICU care

PREVENTION

PREVENTION

A- Direct Intervention:
1- Identification of women at risk:
a- maternal malnutrition
b- heavy work load
c- medical illnesses
d- infections especially urinary
e- raised blood pressure

PREVENTION

A- Direct Intervention:
1- Identification of women at risk:
f- too many pregnancies
g- close spacing between births
h- multiple pregnancy
i- under 18 & over 35


PREVENTION
A- Direct Intervention:
1- Identification of women at risk:
J- Short stature
k- Poor weight gain in pregnancy
l- ethnicity
m- pscychological stress
n- Rural residence
o- previous LBW
P- OTHERS..ALCOHOL

PREVENTION

B- Indirect Intervention:
1- Family planning
2- Sanitation
3- Avoid smoking
4- Nutritional care
5- Combating poverty and deprevation




SMOKING & LBW

• 1-Decreases maternal appetite

• 2-Direct toxic effect
• 3-Nicotine is a vasoconstrictor leading to placental insufficiency
• 4-raised carbon monoxide levels

Leading Causes of Death:

1- Atelectasis,Hyaline membrane disease and surfactant deficiency.
2- Life threatening malformations
3- Pulmonary heamorrhage
4- Intracranial bleeding following anoxia and trauma
5- Pneumonia and infections

Latest Recommendations

It is recommended that labor not be medically induced before 39 weeks unless required for other medical reasons. The same recommendation applies to cesarean section


There is significant evidence that long term (> one year) use of folic acid supplement preconceptionally may reduce premature birth

The chance of survival at less than 23 weeks is close to zero, while at 23 weeks it is 15%, 24 weeks 55% and 25 weeks about 80%.The chances of survival without long term difficulties is less. In the developed world overall survival is about 90% while in low income countries survival rates are about 10%

About 75% of nearly a million deaths due to preterm delivery would survive if provided warmth, breastfeeding, treatments for infection, and breathing support. If a baby has cardiac arrest at birth and is before 23 weeks or less than 400 gms attempts at resuscitation are not indicated

In a 2012 policy statement, the American Academy of Pediatrics recommended feeding preterm infants human milk, finding "significant short- and long-term beneficial effects," including lower rates of necrotizing enterocolitis (NEC).

Iraq

A high percentage of LBW in the Iraqi community points to deteriorating health status of pregnant women, younger age at marriage,inadequate prenatal care .

Harvard Report

Today levels of LBW in Iraq has reached unprecedented rates, ranging from
31-50% of all births have been recorded by international bodies in Dyala , Anbar
and suburbs of Baghdad due to war.

Historical Figuers

Johannes Kepler (born in 1571 at 7 months gestation).
Isaac Newton (born in 1643), small enough to fit into a mug)
Winston Churchill (born in 1874 at 7 months gestation).


Contemporary Figures
Stevie Wonder Who is blind due to retinopathy of prematurity

Winston Churchill

Newton

Thank You