antenatal care and screening demonstration Flashcards
Function of first trimester
Gestational age
- Multiple pregnancies
- Miscarriage
- Abnormalities e.g. ectopic pregnancy/ hydatidiform mole
what can be seen on first trimester
- 4.5 weeks: fluid filled gestational sac
- 5 weeks: Yolk sac
- 5.5 weeks: Fetal pole\
- 6 weeks: Fetal heart pulsation
What is the Crown rump length?
- Once fetal pole has been identified can be measured
- From one end of embryo to another
- Length corresponds to age of embryo so allows estimated delivery date to be estimated
Downs screening in first trimester?
Ultrasound (NT) and combined biochemical testing
- hCG and PAPP-A
Downs screening in second trimester?
- Blood tests
- Between 15-20 weeks
- AFP
- HCG
- UE3: unconjugated eostriol
- Inhibin A
When are major neural tube detected and what is used to detect them?
- In second trimester: 15-20 weeks
- AFP used to detect them
How does Neural tube defect testing work?
-AFP used to detect them
o A fetal glycoprotein produced by the yolk sac, fetal GI tract and liver
o AFP peaks in fetus in 2nd trimester and in mother at 30 weeks gestation
o Maternal serum AFP >2.0 over the median is considered abnormal
Main function of second trimester ultrasound?
- Detects most but NOT ALL major abnormalities
- Mainly structural abnormalities rather than chromosomal
- Can see cord insertion
- Will often lead to difficult questions regarding termination of pregnancy
some examples of neural tube defects?
- cystic zygoma
- diaphragmatic hernia
- Dilated renal pelvises
what abnormalities can be associated with umbilical cord?
Exomphalos: abdominal contents herniate into the umbellical cord
Gastroschisis: bowel herniates outside of abdominal wall
What measurements are taken to assess fatal growth?
- Head
- Abdomen
- Femur
What additional measurements can be taken to assess fatal growth?
- LIQUOR VOLUME: fluid around babies head
2. Placental site
