Fetal Development and Teratogens — Quick Notes

Three stages: Germinal, Embryonic, Fetal
Germinal: conception to about $2$ weeks
Embryonic: weeks $3-8$ ; most vulnerable period for teratogens; CNS develops earliest and longest
Fetal: from week $9$ to birth

Teratogens = any agent that can cause negative birth defects or developmental issues
Most common teratogens are substances ingested by the mother
Effects depend on: dosage, genetic susceptibility, and timing of exposure
Most dangerous exposure window: embryonic stage

Dosage: higher exposure generally → more severe effects
Genetic susceptibility: some fetuses tolerate or filter exposures differently; effects can vary by sex
Timing: different organs develop at different times; early exposure affects more critical systems

Prescription/nonprescription drugs: Accutane (severe heart, facial, brain defects); antibiotics, antidepressants, hormones, acne treatments
Psychoactive drugs: affect brain/nervous system; caffeine (high intake → stillbirth, miscarriage, low birth weight, potential leukemia risk, obesity risk); alcohol (FASD; no known safe amount; facial, brain, growth defects; cognitive/learning impact)
Nicotine: low birth weight, ADHD, impaired brain development; prefrontal cortex affected; vaping is not safe during pregnancy
Marijuana: cognitive issues, intellectual disabilities, low birth weight, ICU risk, mental disorders
Heroin: withdrawal symptoms in newborn; behavioral issues early life
Maternal infections/conditions: rubella (heart issues, smaller head), syphilis (stillbirth, bone issues), general herpes (brain damage risk with natural birth; C-section reduces risk), HIV/AIDS (risk to child), diabetes (high birth weight, GI issues)
Diet/other risks: low folic acid, mercury-containing fish; obesity → diabetes/heart issues
Maternal age: adolescent pregnancy and advanced age (e.g., $35$ ) ↑ risk of complications; Down syndrome risk ↑ with age
Emotional state: high stress → preterm birth, later ADHD/depression risk

Apgar scale: evaluated at $1-5$ minutes after birth
Five criteria: Appearance (skin color), Pulse (heart rate), Grimace (reflex irritability), Activity (muscle tone), Respiration (breathing)
Scoring: each criterion $0-2$ ; total $0-10$
Interpretation: $7-10$ : generally healthy; <7: may need medical assistance; <4: critical, ICU likely
Preterm birth: birth before $37$ weeks
Low birth weight: < $5 ext{ lb } 8 ext{ oz}$

Kangaroo care: skin-to-skin contact; recommended $2-3$ hours/day
Benefits: higher weight gain, improved breathing/heart function, better sleep, reduced pain, long-term emotional regulation improvements
Soothing and bonding: singing to newborns supports cognitive and linguistic development; improves emotional regulation and sleep

Postpartum period: hormonal shifts (estrogen, progesterone drop) and mood fluctuations
Postpartum depression: sadness, anxiety, or despair after childbirth; lasting typically two weeks or more
Coping strategies: antidepressants (safe with breastfeeding), psychotherapy, social support, light exercise improves sleep

Prenatal development stages: germinal, embryonic, fetal
Teratogens: dosage, genetics, timing; embryonic period most vulnerable
Apgar: 0-10 scale; 7-10 healthy, <7 may need help, <4 critical
Birth outcomes: preterm (<37 weeks), low birth weight (< $5 ext{ lb } 8 ext{ oz}$ )
Postnatal care: kangaroo care, parental bonding, postpartum mental health
Key preventive message: no alcohol during pregnancy; avoid harmful substances; seek support when needed