Post-term New-born
Description
▪ A post-term pregnancy is one that extends beyond 42 weeks’ gestation.
The post-term infant may be LGA, AGA, SGA, or dysmature, depending
on placental function.
Aetiology
▪ The cause of prolonged pregnancy is unknown. Factors associated with
post maturity include anencephaly and trisomy 16 to 18.
Pathophysiology
1. If the placenta continues to function well, the foetus will continue to
grow, which results in an LGA infant who may manifest problems such
as birth trauma and hypoglycaemia.
2. If placental function decreases, the foetus may not receive adequate
nutrition. The foetus will utilize its subcutaneous fat stores for energy.
Wasting of subcutaneous fat occurs, resulting in fetal dysmaturity
syndrome. There are three stages of fetal dysmaturity syndrome.
▪ Stage 1- Chronic placental insufficiency
2.
▪ Dry, cracked, peeling, loose, and wrinkled skin
▪ Malnourished appearance
▪ Open-eyed and alert baby
▪ Stage 2– Acute placental insufficiency
4.
▪ All features of stage 1 except point iii
▪ Meconium staining
▪ Perinatal depression
▪ Stage 3– Subacute placental insufficiency
6.
▪ Findings of stage 1 and 2 except point iii
▪ Green staining of skin, nails, cord, and placental membrane
▪ A higher risk of fetal intrapartum or neonatal death
3. The new born is at increased risk for developing complications related
to compromised uteroplacental perfusion and hypoxia (e.g., meconium
aspiration syndrome MAS)
4. Chronic intrauterine hypoxia causes increased fetal erythropoietin and
red blood cell production resulting in polycythaemia.
Description
▪ A post-term pregnancy is one that extends beyond 42 weeks’ gestation.
The post-term infant may be LGA, AGA, SGA, or dysmature, depending
on placental function.
Aetiology
▪ The cause of prolonged pregnancy is unknown. Factors associated with
post maturity include anencephaly and trisomy 16 to 18.
Pathophysiology
1. If the placenta continues to function well, the foetus will continue to
grow, which results in an LGA infant who may manifest problems such
as birth trauma and hypoglycaemia.
2. If placental function decreases, the foetus may not receive adequate
nutrition. The foetus will utilize its subcutaneous fat stores for energy.
Wasting of subcutaneous fat occurs, resulting in fetal dysmaturity
syndrome. There are three stages of fetal dysmaturity syndrome.
▪ Stage 1- Chronic placental insufficiency
2.
▪ Dry, cracked, peeling, loose, and wrinkled skin
▪ Malnourished appearance
▪ Open-eyed and alert baby
▪ Stage 2– Acute placental insufficiency
4.
▪ All features of stage 1 except point iii
▪ Meconium staining
▪ Perinatal depression
▪ Stage 3– Subacute placental insufficiency
6.
▪ Findings of stage 1 and 2 except point iii
▪ Green staining of skin, nails, cord, and placental membrane
▪ A higher risk of fetal intrapartum or neonatal death
3. The new born is at increased risk for developing complications related
to compromised uteroplacental perfusion and hypoxia (e.g., meconium
aspiration syndrome MAS)
4. Chronic intrauterine hypoxia causes increased fetal erythropoietin and
red blood cell production resulting in polycythaemia.
