Birth defects

1.5% of all births show significant congenital abnormalities

2 000 recognised syndromes

Some are associated, e.g. VATER, vertebral, anal, tracheo-oesophageal fistula, renal

Birth defects include disorders caused by labour

Congenital disorders develop before birth from abnormal embryogenesis or genetics

 

Causal relationships

Maternal age

Maternal nutrition

Maternal illness, congenital abnormality incidence doubles in diabetes mellitus

Maternal drug therapy, thalidomide, steroids linked to cleft lip and palate

Maternal drug abuse

Birth order, neural tube defects more common in first pregnancy

Congenital infection, rubella virus – cataracts, deafness, heart defects. Cytomegalovirus – neurological problems

 

CNS

Anencephaly                                                                          Hydrocephalus

Microcephaly                                                                         Neural tube defects

Spina bifida                                                                           Foetal alcohol syndrome

 

CVS

Half of all birth defects

Atrial septal defects

Ventricular septal defects

Patent ductus arteriosus

Tetralogy of Fallot - pulmonary stenosis, VSD, deviation of the aortic origin to the right, hypertrophy of right ventricle.

 

RS

Choanal atresia (without opening or narrowing) - prevents the passage of air from the nasal passages into the pharynx

Microgathia - small lower jaw may result in posterior displacement of the tongue

Diaphragmatic hernia - loops of bowel may herniate into the chest causing significant respiratory difficulties

 

Locomotor system

Developmental dysplasia of the hip (congenital dislocation)

Extra fingers

Webbing of fingers

Missing limbs or part of limbs

 

GIT

Cleft lip / palate

Atresia (narrowing) of the oesophagus

Trachea / oesophagus fistula

Intestinal obstruction - may be complete or incomplete, distal or proximal to the ampulla of Vater

Omphalocele - defect in the umbilical ring allows bowel to protrude

 

GU

Hypospadias – urethral orifice situated on the ventral surface of the penis, anywhere from glands to base

Ureteric reflux

Non descended testes