Obstetric 3 Flashcards
pregnancy and radiography
- avoid plain film radiographs in 1st trimester, esp trunk or back
- abdominal lead shield gives some protection
pregnancy and CT
not recommended in any trimester
pregnancy and MRI
considered low risk and preferential to CT
pregnancy and dx ultrasound
- commonly used, but video display may increase thermal effects
- esp in 3rd trimester
dilutional anemia =
increased blood volume, even with compensatory increase in EPO and RBCs
EPO/RBC norm for pregnancy:
~ 10.5 g/dL
EPO/RBC norm for normal women:
~ 12-16 g/dL
chorionic villus sampling used for
early detection of genetic disorders
chorionic villus sampling risks
1-2% chance of miscarriage
amniocentesis performed when
16-18 weeks
amniocentesis risks
- most sources cite 0.5-1% chance of miscarriage
- depends on baby health, timing, high risk pregnancy
What is done in chorionic villus sampling?
- sample of chorionic villi are removed from the placenta for testing
- taken through cervix or abd wall
- usu performed at 10-13 weeks
What are chorionic villi?
- wispy projections of placental tissue
- share the baby’s genetic makeup
How is an amniocentesis performed?
amniotic fluid removed from uterus for testing or treatment
Why is an amniocentesis performed?
- genetic testing
- fetal lung testing
- dx of fetal infection
- tx
When is amniocentesis used as tx?
can accumulate too much fluid and some must be drained
precautions with pregnancy and lactation: drugs
- anything that can cross the placental barrier may be harmful to the baby
- restrictions during lactation
What types of restrictions during lactation are there for drugs?
- if allowed, should be taken 30-60 minutes after breastfeeding AND
- 3-4 hrs before next feed
What are the FDA categories in pregnancy?
Category A Category B Category C Category D Category X
Category A pregnancy
controlled human studies show no fetal risks
Category B pregnancy
animal studies show no fetal risks (no human studies available)
Category C pregnancy
- no adequate human or animal studies
- risk cannot be ruled out
Category D pregnancy
- evidence indicates fetal risk
- benefits thought to outweigh the risks
Category X pregnancy
- contraindicated in human pregnancy
- risks outweigh any potential benefits
