Embryology Anomalies------------------------- Flashcards
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when an embryo implants somewhere other than the uterine lining»_space; first sign typically abdominal pain during early pregnancy
ectopic pregnancy
pregnancy that is due to scarring of uterine tubules, surgery indicated if oviduct in danger of bursting or implantation occurring near a major blood vessel
tubal pregnancy
a type of ectopic pregnancy that often results in normal births via surgery due to maternal hemorrhaging
intra abdominal pregnancies
when remnants of the primitive streak persist and proliferate
sacrococcygeal teratoma
disorganized proliferating chorion (placenta) resulting from an abnomal pregnancy
hydatidiform mole
triploid
fetus present but not viable
very low malignancy potential
partial hydatidiform
46 chromosomes, all of paternal origin
no fetus present
potential invasiveness and even metastatic malignancy
complete hydatidiform
irregular menstrual cycles
oligomenorrhea
villa penetrate into myometrium (muscle layer of uterus)
placenta accreta
full thickness of myometrium
placenta percreta
placenta covers internal uterine os»_space; bleeding during 3rd trimester and Cesarean section required
placenta previa
due to umbilical vessels being longer the cord itself
false knots
inserts at edge of placenta
battledore placenta
inserts into fetal membranes with vessels then transversing between amnion and chorion»_space; easily torn
velamentous insertion
result from tears in the amnion»_space; origin most likely infection or toxic insult
can encircle head or extremities»_space; amputations, ring constrictions or craniofacial abnormalities
amniotic bands
excessive amniotic fluid»_space; can be due to multiple causes
inability to swallow
maternal diabetes
idiopathic
polyhydramnios
too little amniotic fluid
placental insufficiency
compression of fetus
oligohydramnios
results in pulmonary hypoplasia
occurs posterolaterally allowing abdominal contents to enter thoracic cavity
congenital diaphragmatic hernia
children have behavioral and learning difficulties»_space; caused by moderate consumption or 1-2 binges
fetal alcohol effects
growth, physical and mental anomalies associated with children who mother was a chronic alcoholic during pregnancy
fetal alcohol syndrome
constricts uterine blood vessels
nicotine
maternal consumption believed to be most common cause of mental deficiency»_space; more pronounced effects if poor nutrition also a factor
alcohol
cause masculinization of female fetuses
androgens
component of birth control pills and to this syndrome
progesterone
VACTERL
vertebral, anal, cardiac, tracheal, esophageal, renal and limb anomalies
genital tract anomalies in both sexes and increased incidence of adenocarcinoma of the vagina later within the child
diethylstilbesreol
yellowing of teeth, low enamel deposition and diminished growth of long bones
tetracycline
handful of cases reporting 8th cranial nerve damage
streptomycin
causes meromelia
utilized as to treat morning sickness
thalidomide
causes mental retardation and motor dysfunctions
most commonly obtained through fish and seafood
mercury
causes increased miscarriage, multiple anomalies, IUGR and functional deficits
maternal exposure to sub-clinical levels can cause neurobehavioral and psychomotor disturbances
most common source is dust or chips from paints used prior to 1978»_space; many other potential sources as well
lead
produce IUGR and skin discoloration
coolant/insulator used until 1979»_space; persists in environment and accumulates in sports fish
polychlorinated biphenyls (PCBs)
interferes with eye and/or ear development
rubella (German measles)
highly endogenous virus
usually asymptomatic in mothers, but can be lethal in infants or produce mental retardation
cytomegalovirus
asymptomatic in mother, but affects CNS in infants
obtained from raw meats and the feces of domesticated animals, particularly cats
Toxoplasma gondii
evidence for low teratogenic potential
herpes simplex, syphilis, varicella and HIV
maternal infection with pyrogenic viruses
hyperthermia
a cause of birth defects – high does rapidly kills proliferating cells»_space; also a mutagen
radiation
poorly controlled diabetic mother 3-4X greater risk of birth defects, plus higher incidence of stillbirths, neonatal deaths and macrosomia
diabetes
high serum phenylalanine teratogenic for mental retardation, microcephaly and heart defects
teratogenicity alleviated by mother maintaining a low phenylalanine diet
phenylketouria
animal studies link several vitamin and mineral deficiencies to birth defects, but only two widely accepted for humans
nutritional deficiencies
leads to congenital cretinism»_space; results in retarded growth and brain development
iodine deficiency
leads to neural tube disorders
folate deficiency
failure of recanalization leads to…
stenosis
narrowing of lumen
stenosis
lack of lumen
atresia
typically due to loss of blood supply to portion of an organ
atresia
intestines remain herniated into umbilical cord at birth
omphalocele
umbilicus does not properly close»_space; abdominal contents herniate upon increased abdominal pressure
umbilical hernia
incomplete closure of lateral folds resulting in protrusion of viscera
gastroshisis
results in small intestine on right and entire colon on left»_space; fairly common
nonrotation
results in appendix located near liver
subhepatic cecum
small intestine wrapped in a hernia-like mesentery sac
internal hernia
twisting of intestines»_space; creates obstruction
volvulus
cause constriction of artery (loss of blood supply»_space; gangrene) or cause artery to be anterior to intestine (compress on intestine causing obstruction)
mal-rotations
proximal omphaloenteric duct fails to degenerate, leaving a blind-ends pouch»_space; can become inflamed and mimic appendicitis
Meckel’s diverticulum (ileal diverticulum)
produces umbilicus that is open to ileum»_space; allows release of digestive material
omphaloenteric fistula
can become infected»_space; painful with possible drainage through umbilicus
omphaloenteric cysts
can allow blood bleeding through umbilicus
persistent fibrous cord with vitelline artery
urethra, vagina and rectum empty into a single vestibule
persistent cloaca
anal canal ends blindly, or forms fistula with vagina or urethra
anal agenesis, with or without fistula
anus exists anterior to anal pit
anoperitoneal fistula
use of exogenous surfactant
maternal administration of glucocorticoids accelerates surfactant production
premature infants lack surfactant and cannot ventilate properly
infant respiratory distress syndrome
