Prenatal Development

Question 1

What are the 3 prenatal developmental stages?

Answer 1

zygote (fertilization - 2 wks), embryo (3 -8 wks), fetus (9-38 wks)

Question 2

Define zygote and the zygote period.

Answer 2

fertilized egg; begins at fertilization & ends when ovum implants itself in uterus wall (2 week process)

Question 3

Define embryo and embryo period.

Answer 3

term given to zygote once it is completely embedded in uterine wall; critical time of development of 3rd - 8th week; development of heart, cns, eyes, limbs, ears, teeth, palate and external genitalia occurs

Question 4

Define the Placenta.

Answer 4

link between the mother & fetus - allows nutrients to pass to fetus; allows waste material to be removed

Question 5

Define the umbilical cord.

Answer 5

attached to placenta at one end & to the child on the other end (20 inches in length)

Question 6

How big is the embryo by the end of the 8 week period?

Answer 6

1.5-2 inches in length, .66 weights, all organs now present

Question 7

Describe the fetus period.

Answer 7

End of 2nd month - birth; head and internal organs develop first, limbs and digits last.

Question 8

Define proximodistal growth.

Answer 8

Growing near to far.

Question 9

Define cephalocaudal growth.

Answer 9

Growing head to tail.

Question 10

Define Teratogens.

Answer 10

external factors causing malformations or physical defects in fetus.

Question 11

Give examples of teratogens.

Answer 11

prescription and non-description drugs (1 dose lasts 48 hours in adult/ 4-5 days in fetus), chemicals (mercury, hydrocarbons, lead), nicotine, caffeine, alcohol

Question 12

Describe Fetal Alcohol Syndrome and Disorder.

Answer 12

facial malformations, retarded physical growth, impaired language development, attention deficits, learning impairment, mental retardation (FAS is leading cause of MR in the US); FAS - 2-7 per 1K, FASD 20-50 per 1K

Question 13

Give examples of diseases that affect prenatal development.

Answer 13

German measles (Rubella), diabetes, herpes, AIDS: risk of transmission from mother to fetus is 35-60%; transmitted through placenta or the virus being present in the lining of brith canal.

Question 14

Define an abortion.

Answer 14

fetus born before 20th week, weighing less than 500 grams/1 lb

Question 15

Define an immature birth.

Answer 15

fetus born between 20th -28th week weighing 1-2 lbs; some now survive

Question 16

Define a premature birth.

Answer 16

fetus born 29th-36th week weighing 2-5.5 lbs; many now survive

Question 17

Define a mature birth.

Answer 17

fetus born 37-42 week weighing 5.5 lbs +, anything past this is considered a post-mature birth

Question 18

Describe the first stage of labor.

Answer 18

longest stage; may be 12-24 hours; contractions of low intensity, cervix begins to dilate

Question 19

Describe the second stage of labor.

Answer 19

delivery; starts with baby’s head at opening of cervix, ends with birth of baby

Question 20

Describe the third stage of labor.

Answer 20

Afterbirth; placenta and other membranes are expelled.

Question 21

Compare natural birth to Cesarean birth.

Answer 21

3 stages are bypassed for a C-section; 32% of all births; rates have increased 60% from ‘96-2009

Question 22

What is the APGAR scale?

Answer 22

evaluation of heart rate, respiratory, muscle tone, color, reflex irritability; done at 1,5, & 10 minutes; Max score is 10, average is 7, if score is 4 or less, special care is needed