birth defects and markers

gastroschisis

intestines herniate out the abdominal wall and are not membrane enclosed, common in mothers under 20

spina bifida

neural tube defect occurring in 1/1000 births

cleft palate

failure of palatal shelves to fuse, in 1/700 births and associated with over 400 syndromes

tetralogy of fallot

4 heart defects in 1 (VSD, overriding aorta, pulmonary stenosis, right ventricular hypertrophy), strong association with 22q11.2 deletion syndrome

congenital pulmonary airway malformation

multicystic mass of abnormal lung tissue, not usually genetic

omphalocele

a defect of abdominal wall where there is possible herniation of organs into a sac covered by a membrane, associated with trisomies 13 and 18 and BWS

renal agenesis

absence of 1+ kidneys, is sporadic

congenital diaphragmatic hernia

respiratory and GI, herniation of abdominal contents into chest, genetic with trisomy 13,18, microdeletions, cornelia de lange, and Fryns syndrome

anencephaly

absence of major portions of brain, detected by first trimester NT scan, trisomies 18 and 13

tracheoesophageal fistula

connection between trachea and esophagus is abnormal, usually detected after birth

cardiac rhabdomyoma

benign cardiac tumors, strongly associated (60-95%) with tuberous sclerosis

polydactyly

extra fingers/toes, can range from 1-50% recurrence due to autosomal dominant inheritance

clubfoot

abnormal inward rotation of foot/ankle, isolated/multifactorial, oligohydramnios, positional, trisomies 13 and 18 and over 250 other syndromes

hydrops

abnormal fluid accumulation in 2+ compartments, detectable in any trimester

echogenic bowel

bowel is brighter than bone, can be normal, associated with infection, CF, or trisomy 21

choroid plexus cyst

small cyst in choroid plexus of lateral ventricles, either normal variation or trisomy 18 sign

absent/hypoplastic nasal bone

short or absent nasal bone, can be normal variant (more frequent in certain ancestries) or associated with trisomy 21

echogenic intracardiac focus

bright spot in fetal heart due to calcium deposit, normal variant (seen more in Asian ancestry) but could also be associated with trisomy 21

short femur

femur length below expected percentiles, could be normal, genetic (trisomy 21, skeletal dysplasia), or a sign of fetal growth restriction

pyelectasis

urinary where there is a dilation of renal pelvis/urinary tract, could be normal variant or associated with trisomy 21