2.3 Biological Beginnings and Prenatal development II

20 weeks

can respond to sound

7 to 8 weeks

arteries and veins of heart are complete

8 to 9 weeks

thumb sucking can be observed

22 to 26 weeks

If born prematurely baby can survive

30 weeks

breathing motions can be observed

Periods of prenatal development

germinal, embryonic, and fetal

First trimester

grow up to 3in, 1oz, spinal cord, nervous system, gastrointestinal system, heart, lungs, heartbeat and brain forming at 8 weeks, move arms legs and fingers, smile frown suck and swallow, move to touch and gender at 12 weeks.

Second trimester

14 in, 1lb, skin protected by vernix and lanugo, heart beat with stethoscope, eyes open at 24 weeks, suck thumb and strong grip, nails, hair, lashes, and eyebrows, roll over and movement, can feel pain

Vernix

milky substance

Lanugo

fine hairs

Third trimester

19 in, 6 to 7 lb, lanugo nearly gone, age of viability 22 to 26 weeks, usually upside down position, bones in skull are soft and pliable, body fat adding, less movement, very responsive to stimulation like touch sound and light

Teratogens

environmental agents that interfere with natural grown and produce birth defects

Variables that affect the effects of teratogens

baby gestational age, amount of teratogen, susceptibility

Baby gestational age

systems in the process of development are more susceptible, susceptibility begins around three weeks after conception

Amount of teratogen

more exposure is more damage

Susceptibility

qualities inherent to mother or child may influence whether or to what extent the teratogen has an effect

Nicotine

miscarriage, preterm birth, low birth weight, learning difficulties, SIDS

Alcohol

fetal alcohol syndrome, cognitive and emotional problems

Xray

gene mutation, possible deformity

Herpes

miscarriage, low birth weight, intellectual disability

Toxoplasmosis

eye and brain damage

Malnutrition

nervous system damage, respiratory illness, poor health

Stress

miscarriage, prematurity, low birth weight, respiratory illness, birth defects, b/c increased blood is sent to mothers brain, heart and limbs leaving less for uterus and baby and the hormones associate with this affect the baby

Advanced maternal age

chromosomal defects, miscarriage, infertility

Stage I early labor and active labor

longest stage, ends with cervix is completely dilated, 8 to 12 hours for early section with contractions lasting 30 to 45 seconds with 5 to 30 minute breaks and active section takes 3 to 5 hours with contractions lasting 45 to 60s with 3 to 5 minutes between

Stage II delivery of the baby

begins after cervix is completely dilated to 10cm ends with baby is delivered, between 20 minutes to 2 hrs, strong urge to push and sense of pressure at the rectum, baby head will crown/ become visible

Stage III delivery of the placenta

5 to 10 min, contractions start again placenta separates from uterine wall, mother experience shivering and shaking

Types of drugs used during child birth

analgesics, anesthesia, and oxytocics

Analgesics

relieve pain, narcotics, barbiturates, and tranquilizers

Anesthesia

blocks sensation of pain in certain area of the body general form may block consciousness

Oxytocics

synthetic hormones that stimulate contractions to induce labor

Lamaze

breathing techniques and education to help relieve pain and control fear

Postpartum

6 weeks, mothers body heals and emotional adjustment to childbearing and childrearing