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Lecture Details[]

Louise Newman; Week 2 MED1022; MotM

Lecture Content[]

Inadequate maternal nutrition may result in premature birth and low birth weight, and a lack of folate increases the risk of a baby developing spinal bifida. Stress may also have an impact on birth weight and premature birth. Age is a general risk factor for congenital abnormalities such as Down syndrome, and older mothers are more likely to have problems with miscarriage and stillbirths. Drugs also impact the development of a fetus, teratogens are agents that cause abnormal prenatal development. Many legal and illegal drugs are teratogens including marijuana, alcohol, nicotine, aspirin and caffeine. Diseases can also have teratogenic effects, such as AIDS, cytomegalovirus, herpes, rubella and syphilis can cause neurological disorders, deafness, blindness, intellectual disability and so on. Environmental hazards that can cause congenital deformities include lead, mercury, X-rays and polychlorinated biphenols.

The effect of the teratogen also depends on the genotype of the organism, and changes over the course of fetal development. Each teratogen affects one specific aspect of development, varies with dose, and may not be evident immediately at birth. Genetic counselling assists in assessing the chance of a child having an inherited disorder. A mother at greater risk may be subjected to prenatal diagnosis, such as ultrasound, amniocentesis, and chorionic villus sampling. If a disorder is diagnosed, medicine can be administered to the fetus, surgery can correct some developmental disorders such as spina bifida, and genetic engineering can replace defective genes with normal ones, although this is difficult and rare.

Reflexes of the newborn are assessed as they may reflect the health of the child’s nervous system. The ability to suck is an important reflex, and others appear to be indicators for later voluntary motor behaviour. The APGAR index is used to assess the newborn’s health. This includes appearance of skin tone, pulse, grimace for reflexes, activity for muscle tone, and respiration. The neonatal behavioural assessment scale is also used, to assess the newborn’s autonomic, motor and social systems.

A newborn has a few distinct states: alert inactivity, waking activity, crying and sleeping. A basic cry starts softly and becomes louder, often occurs when the baby is hungry or tired. A mad (angry) cry is louder and more intense, and the pain cry is very loud and followed by a pause then gasping. Babies sleep on average 16-18 hours per day, with a four hour sleep period followed by one hour of wakefulness. Soon after birth, by about three or four months, newborns typically sleep through the night.

Growth is fastest in infancy than during any other time, infants double their weight by three months, and triple by one year. Average birth weight is not the same as normal birth weight. Because this growth is so rapid, babies must be fed adequately, and breast-feeding is the best way to do this. Foods should be introduced gradually, one at a time.