(2) Prenatal Development Flashcards
What is a fertilized egg called?
zygote
What happens in the Zygote or Germinal Stage?
Conception to implantation
When does the Zygote or Germinal stage occur?
0-2 weeks
What is a Amniotic sac?
fluid-filled membrane protecting embryo
What is a Placenta?
Disc-like structure connecting embryo to uterus
What is an Umbilical cord?
tube connecting embryo to placenta: provide oxygen and nutrients, removes carbon dioxide and waste
When does an embryo develop?
3-8 weeks
At what stage is miscarriage highest?
Embryo stage
What develops when a foetus grows?
Functional development, Brain development, Responds to stimulation
What happens in the 12th week of pregnancy?
Can tell sex of child, child develops reflexes
What happens between weeks 17-20 weeks of pregnancy?
Mother can feel child move
What happens if a child is born 22-26 weeks into pregnancy?
viability – if it is born it has a chance of survival
What is Teratogen?
an environmental agent that causes prenatal damage
What happens to an unborn child who is exposed to teratogen?
Effects during critical/sensitive periods, effects are specific, longer exposure is worse, some have no effect on mother, maternal/foetal genes may counteract effect
What is Thalidomide?
drug for morning sickness (1957-61), caused structural abnormalities in limbs and faces
What is DES?
hormone to prevent miscarriage (1947-64), linked to reproductive problems and cancers in offspring
What can occur if caffeine is consumed during pregnancy?
miscarriage, low birth weight (LBW), avoid > 200mg
What can occur if tabacco is consumed during pregnancy?
chemicals in smoke -> miscarriage and prematurity
What does nicotine effect?
Nicotine affects placenta -> poor nutrition -> LBW
How can Foetal Alcohol Syndrome (FAS) affect an infant?
Stunted growth, physical defects, often mental retardation
When is FAS most lethal?
Last trimester worst – brain is developing the most
How many infants are affected by FAS in the UK?
1-5% affected in UK
What are examples of radiation?
Radiation (atomic bomb, nuclear reactor meltdowns, ordinary X-rays)
What affects can radiation have?
Miscarriage, stunted growth, physical defects, cancer
What are examples of pollution?
Pollution (lead, mercury, PCBs)
What affects can pollution have?
Prematurity, LBW, cognitive delays
What is Toxoplasmosis?
parasitic infection in cats and raw meat leads to brain and eye damage to child
What effects can HIV/AIDS have?
mortality, small head, physical and mental defects
What is Rubella?
virus damages eyes, ears, heart; causes mental retardation
What is CMV?
virus with mild (or no) flu-like symptoms
What is herpes?
sexually transmitted virus, damages eye, brain, motor system
What is the zika virus?
Mosquito-borne infection, identified in Uganda (1947)
How can the zika virus effect a mother?
Mild fever
What is the zika virus linked to in infants?
infant microcephaly (small brain)
How does the zika virus effect infants?
Infect foetal brain tissue, lifelong sensory, motor and cognitive disability
What are the risks of pregnancy in older women?
Miscarriage and chromosomal damage risks increase with age
What is Toxemia/Pre-eclampsia?
pregnancy-caused high blood pressure -> restricted growth, preterm birth, stillbirth
What affects can (Gestational) Diabetes have on infants?
high birth weight, preterm birth, temporary breathing problems
What does APGAR stand for?
activity, pule, grimace, appearance and respiration
What does a 0-3 APGAR score suggest?
severely depressed
What does a 4-6 APGAR score suggest?
moderately depressed
What does a 7-10 APGAR score suggest?
excellent condition
How many weeks does an infant have to be to be considered preterm?
Less than 36 weeks, less than 32 is very preterm, extremely is less than 26
What is the average weight of a preterm infant?
2.3kg
What are the risks to preterm babies?
Risk of cognitive delay, inadequate surfactant (liquid in lungs that sends oxygen into blood), May cause respiratory distress syndrome
What is a normal birth weight?
3.5kg
When do infants of LBW typically catch up?
4 years
What are long term effects of LBW?
cognitive and motor issues
What did Thoman et al (1995) investigate?
The Breathing Bear with Preterm Infants experiment
What did Field (1990) investigate?
Massage Stimulates Growth in Preterm Infant, Treated infants gained more weight per day and were discharged from hospital several days earlier than control infants
Why might preterm babies get less attention?
- Physical appearance
- High-pitched cry
- Feed difficulties
- Lower responsiveness
- Hospital or home-based interventions aim to improve parent-infant interaction
