Birth Defects and Teratology Flashcards

Vocabulary flashcards covering birth defects, classification, principles of teratology, specific teratogenic agents, limb/facial anomalies, and prenatal diagnosis methods.

Birth Defect

Any structural anomaly present at birth, caused by genetic abnormalities, environmental exposures, or unknown etiology.

Malformation

Defects of organs or body parts due to an intrinsically abnormal developmental process.

Deformation

Abnormalities of the position of body parts due to extrinsic intrauterine mechanical forces that modify a normally formed structure.

Disruption

Defects of organs or body parts that result from destruction of or interference with normal vascular development.

Dysplasia

Anomalies that result from the abnormal organization of cells into tissue.

Syndrome

A group of anomalies occurring together that have a specific common cause, indicating that a diagnosis has been made and the risk of recurrence is known.

Association

The nonrandom appearance of two or more anomalies that occur together more frequently than by chance alone, but whose cause has not been determined.

CHARGE Association

An association pattern comprising Colobomas, Heart defects, Atresia of the choanae, Retarded growth, Genital anomalies, and Ear abnormalities.

VACTERL Association

An association pattern comprising Vertebral, Anal, Cardiac, Tracheo Esophageal, Renal, and Limb anomalies.

Major Malformations

Malformations that have medical and/or social implications, often require surgical repair, or are life-threatening (e.g., neural tube defects, orofacial clefting).

Minor Malformations

Anomalies that have mostly cosmetic significance, rarely require surgical intervention, and represent normal variation in the general population (e.g., ear tags, simian crease).

Period of Embryogenesis

The third to eighth weeks of gestation, which represents the most sensitive period for inducing birth defects.

Pneumonia Alba

A form of chronic pneumonia seen in stillborn and newborn infants dying of congenital syphilis.

Cleft Lip

An upper lip malformation with or without cleft palate, seen in 1/900 births and occurring more frequently in males.

Cleft Palate

A malformation with or without cleft lip that is seen in about 1/2500 births and may involve only the uvula or extend through the soft and hard palate.

Cleft Hand or Foot

A rare lobster-claw deformity where 1 or more central digital rays or digits are absent, dividing the hand or foot into 2 opposing parts, usually with remaining digits fused.

Club Hand

Congenital absence of radius where the radius is partly or totally absent, causing the hand to deviate to the radial side and the ulna to bow.

Club Foot

Talipes equinovarus; a common anomaly seen more frequently in males where the sole of the foot is turned inwards, adducted, and plantar flexed at the midtarsal joint.

Brachydactyly

An uncommon inherited dominant trait characterized by abnormal shortness of fingers or toes due to size reduction of the phalanges.

Polydactyly

A common inherited dominant trait characterized by the presence of extra fingers or supernumerary digits.

Syndactyly

One of the most common malformations characterized by fused or webbed digits resulting from failure of differentiation between 2 or more digits.

Congenital Hip Dislocation

A common phenomenon seen more frequently in females where the hip joint capsule is abnormally relaxed at birth with underdevelopment of the acetabulum and femoral head.

Sympodia

Also known as sirenomelia; a condition in which the lower limbs are fused, always associated with a disturbance in pelvic formation.

Arachnodactyly

A condition seen in Marfan's syndrome characterized by thin fingers and toes with elongated phalanges, metacarpals, and metatarsals.

Diethylstilbestrol (DES)

A synthetic hormone exposure implicated in malformation of the uterus, uterine tubes, and upper vagina, and carcinogenic to female offspring later in life (16 to 22 years).

Thalidomide

A sedative-hypnotic agent whose intrauterine exposure causes meromelia and other limb malformations, as well as defects of the external ears, heart, and digestive tract.

Cordocentesis

A method of prenatal diagnosis also known as percutaneous umbilical blood sampling.

Chorionic Villus Sampling (CVS)

A invasive prenatal diagnostic technique used to sample fetal placental tissue.