Prenatal development Flashcards
What is classed as prenatal development?
From contraception to birth.
What are the rough stages of prenatal development?
Zygote, cells specialise (up to two weeks)
Embryo sexual development and organs develop. (2-8 weeks)
Foetal, organs fully develop (up to 2 months).
What happens to the zygote?
Starts as a single cell containing all chromosomes and undergoes rapid cell division.
What happens during the embryo phase?
Development at a rapid pace, most critical to damage due to crucial organ development.
At what stages of embryonic development do The brain and spinal cord, heart and movement develop?
18 days heart develops, 3 weeks it beats, 2 weeks and 4 days brain and spinal cord develop,
Moves between 5-6 weeks.
At what stages of the foetal development does sensitivity, sound and taste occur?
Sensitive to touch at 13-14 weeks, 20 weeks can respond to sound, 25 week can respond to taste.
What can the foetus do in regard to taste by week 25 and what does this show?
Decrease swallowing at bitter tastes and increase at sweet. Showing its an innate evolutionary response.
How did we study the abilities of a foetus?
Using scans which are low cost and safe, Foetal heart rate (FHR) in order to study responses.
What has been studied to do with foetus’ and sound?
Mother saying a rhyme everyday between weeks 30-37, found a heart rate decrease after birth when hearing the rhyme showing calmness to the mother.
Same was found when music was played after birth that was repeated during pregnancy.
What is the technique called when a baby is familiar to something that was used during pregnancy?
Exposure learning.
When does learning begin?
During utero when the baby learns how to swallow and intake nutrients.
How common is a birth deficit and what is usually the cause?
3-5% and teratogens.
What is a teratogen
Factors that increase risks in pregnancy, e.g. diet, smoking, alcohol and certain medication.
What was the study found for diet in Gambia?
Babies born during harvest season who’s mothers had available crops to eat were born healthier whereas those who were born outside this season had more implications.
What was found in the Dutch study of famine in 1943-7?
That the babies born during the famine had a 2x more likelihood to develop heart disease, schizophrenia, diabetes and more and that this was a generational effect.
What is the critical period?
Time in which a particular organ or body part is more susceptible to teratogenic damage.
Why has no experimental research not been done into teratogen?
Because it is unethical to purposely harm a foetus or mother.
What stages are more susceptible to teratogens and why?
Zygote: most do not know of pregnancy and therefore babies can be easily lost due to teratogens.
Embryo: most susceptible to damage due to most development.
Foetus: No major defects but smaller illnesses due to most of the baby already being formed.
What did the study by Ness 1999 find about cocaine and smoking?
400 in sample miscarried and 570 did not. The self report techniques found no correlation with cocaine due to the unreliability but when urine and hair samples were analysed was found cocaine increased miscarriage rates by 1.4 and smoking 1.8.
What did Reissland 2015 find out about smoking and movement in foetus?
That the smoking groups did not move as much and therefore shows that due to CNS development that they will develop slower than non smoking group.
What does foetal alcohol syndrome cause?
Causes permanent birth defects, specifically to the CNS and brain damage, common effects are impaired activity motor control, attention deficit and memory and language problems.
What is the different between preterm and low birth weight?
Preterm is a baby born before 37 weeks, low birth rate is a baby born at full term but lighter than normal e.g. less than 5.5lbs.
How much more likely are babies to die in early infancy if their birth weight is between 3.5-5.5?
7x more likely.
What did Costello et al 2007 find out about low birth weight?
Girls with low birth weight are more likely to develop depression between 13-16?
