1: Fetal Development

time from the first day of the last menstruation

Last Menstrual Period (LMP)

time from the moment of conception; age of developing fetus

Post-conceptual Age/ Embryonic Age

how many weeks less is GA than LMP?

2

how many weeks are full term GA?

37-42 (40wks for calculations)

Chronological Age

days, weeks, or months since birth

a birth that takes place < 37 weeks GA

premature

a birth that takes place < ____ weeks GA is considered premature

37

how to calculate the corrected (adjusted) age?

subtract # of weeks premature from chronological age

how many wks is the embryonic stage?

3-8

how many wks is the germinal stage?

0-2

how many wks is the fetal stage?

9 weeks - birth

what human development stage is most sensitive to teratogens?

embryonic

what are teratogens?

Drug, environmental substance, or maternal condition that is capable of interfering with the development of the fetus

teratogens typically result in a…

birth defect

prevention of birth defects

• Early and regular prenatal appointments

• 400 micrograms of folic acid daily, starting at least a month before getting pregnant

• Do not smoke, drink alcohol, or use recreational drugs

• Discuss medications with MD

• Prevent illness during pregnancy

development continues in what direction?

(during embryonic phase)

cephalocaudal

what starts to develop week 3 GA?

endoderm, mesoderm, ectoderm

endoderm turns into? (3wk embryonic phase)

digestive tract

mesoderm turns into? (3wk embryonic phase)

muscles, skeleton, circulation

ectoderm turns into? (3wk embryonic phase)

skin & nervous system

what starts to develop week 4?

• heartbeat present

• neural Tube Closure

• limb buds form

what starts to develop week 6?

• placental circulation functional through umbilical cord

• brain division and cerebral hemispheres

• CV system functioning

• eyes with eyelids

• vertebrae begins to form

what starts to develop week 8?

• eyes, ears, nose, mouth, fingers, toes, heart, formed

• embryo looks like a human and all tissues formed

at what wk can you call it a fetus?

9

T/F Teratogens are most likely to cause brith defects after week 9

false → most likely 3-8 wks

could cause fetal growth restrictions or placental distress

what begins to develop week 9? (fetal development)

• Rapid proliferation and hyperplasia

• Organ and tissue differentiation continue

• Bones continue to ossify and remodel

• Appearance becomes more proportional

what begins to develop wks 9-16?

• cartilaginous skeleton formed

• swallowing emerges

• external genitalia viable by 12 weeks

• eyes move

• developmental reflexes strengthen

what begins to develop wks 17-20?

• mother can feel fetal movement toward the end of this stage

• skin covered in lanugo: layer of

  fine hair

• adipose tissue

• lung maturation continues

• diagnosis of congenital heart defects

Not able to survive if born before ___ weeks

21

what begins to develop wks 21-29?

• accelerated weight gain

• ongoing lung development, begin to produce surfactant (24wk)

• eyes fully developed by wk 25, REM

fetus is viable at ___ weeks if born prematurely

23

what wk do the lungs begin to produce surfactant?

24

what wk are the eyes fully developed?

25

what is formed by wk 29?

• Hair, nails

• All neonatal reflexes present

• Able to cry audibly

what begins to develop wks 30-38?

• weight gain continues → fat accumulation for insulation over last weeks

• thermal regulation established by 32 weeks

• fetal movements decrease

how should the baby be positioned for proper birth?

• head down (Vertex), face down

• head should be slightly smaller than pelvic outlet

what happens to the baby at birth?

should breathe on their own within a few seconds

shift from fetal circulation to adult circulation

what does APGAR stand for?

appearance, pulse, grimace, activity, respiration

normative values for 1min APGAR scores

7-10: routine care

4-6: some assistance for breathing may be required

< 4: lifesaving measures

normative values for 5min APGAR scores

7-10: normal

< 7: ongoing monitoring every 5 minutes, up to 20

appearance scores for APGAR

2 = pink

1 = extremities blue

0 = pale/blue

pulse scores for APGAR

2 = > 100bpm

1 = < 100bpm

0 = no pulse

grimace scores for APGAR

2 = cries and pulls away

1 = grimaces or weak cry

0 = no response to stimulation

activity scores for APGAR

2 = active movement

1 = arms, leg flexed

0 = no movement

respiration scores for APGAR

2 = strong cry

1 = slow, irregular

0 = no breathing

normal birth weight

> 5 pounds, 8 ounces (2500g)

< 8 pounds, 14 ounces (4000g)

Small for Gestation Age (SGA)

< 5 pounds, 8 ounces (2500g)

Low Birth Weight (LBW)

1500g to < 2500g

Very Low Birth Weight (VLBW)

1000 to < 1500g

Extremely Low Birth Weight (ELBW)

< 1000 g

neuromuscular impairments of FAS

fine and visual motor deficits

impaired balance, coordination, and motor development

cause of fetal alcohol syndrome (FAS)

alcohol → enters baby’s bloodstream through placenta

MSK impairments of FAS

• Facial: smooth philtrum, thin upper lip, broad nose

• Poor Growth, Microcephaly

• Abnormal joint position or function

• Short stature

cardiopulmonary impairments of FAS

heart defects

behavioral/cognitive impairments of FAS

• hyperactivity

• poor memory and attention (intellectual disability)

FAS across the lifespan → infants

• low birth weight

• Irritability

• sensory sensitivity to light

• poor sucking

• Global Developmental Delay

• poor sleep-wake cycles

• increased ear infections

FAS across the lifespan → toddlers

• poor memory capability

• Hyperactivity

• impulsive/lack of fear

• lack sense of boundaries

FAS across the lifespan → school-age

• Short attention span

• Poor coordination

• Difficulty with both fine and gross motor skills

• Learning disabilities

FAS across the lifespan → adolescents

• Trouble keeping up with school

• Low self-esteem from recognizing that they are different from their peers

• Poor impulse control

FAS across the lifespan → adults

Poor life skills → daily obstacles, such as affordable and appropriate housing, transportation, employment and money handling

An array of behaviors seen in the newborn following abrupt termination of gestational exposure to substances

neonatal abstinence syndrome (NAS)

presentation of NAS

• Low Birth Weight

• High-pitched cry, Irritable

• Impaired state regulation

• Hyperactive reflexes

• Transient tone

• Feeding difficulties

• ANS dysfunction

treatment of NAS

gradual wean of substance → replace with morphine, methadone

small head and brain, often with intellectual disability

microcephaly

absence of the cranial vault, failure of rostral neural tube to close resulting in an absence of the cerebral hemispheres.

This condition is incompatible with life

anencephaly

a sac-like protrusion or projection of the brain and the membranes that cover it through an opening in the skull

encephalocele

herniation of the intra-abdominal contents into the base of the umbilical cord – requires progressive compression of abdominal contents and skin closure

omaphalocele

what condition is most common in weeks 16-28?

Pubic Symphysis Dysfunction (SPD) / Pelvic Girdle Pain (PGP)

what condition typically occurs in the second and third trimesters as the baby and uterus grow.

low back pain

what condition often develops during the third

trimester?

diastasis recti

what condition occurs during 2nd and 3rd trimesters, later stages as the baby grows?

sciatica

what condition is often noticed after 30 weeks of gestation (third trimester)?

carpal tunnel syndrome

what condition d/o pregnancy, some reports of increased pain in 2nd and 3rd trimesters

coccyx pain (coccydynia)

what condition can be related to childbirth, particularly difficult labors?

pelvic organ prolapse

what condition happens later stages of pregnancy and post childbirth

incontinence