Prenatal Development

What are the parts and functions of the female & male reproductive systems?

Female Reproductive System

1. Ovaries: Produce eggs (ova) and hormones (estrogen, progesterone)
2. Fallopian tubes: Where fertilization usually occurs; transport egg to uterus
3. Uterus: Muscular organ where the embryo/fetus develops
4. Endometrium: Inner lining of uterus; thickens to support pregnancy
5. Cervix: Opening of uterus; dilates during childbirth
6. Vagina: Birth canal; receives sperm during intercourse

Male Reproductive System

1. Testes: Produce sperm and testosterone
2. Epididymis: Stores and matures sperm
3. Vas deferens: Transports sperm
4. Seminal vesicles & prostate gland: Add fluids to sperm to form semen
5. Penis: Delivers sperm into female reproductive tract

What is the process of fertilization?

1. Mechanism: Occurs when one sperm penetrates one egg
2. Location: Usually happens in the fallopian tube
3. Formation: The sperm and egg nuclei combine to form a zygote
4. Genetic Content: Zygote has 46 chromosomes (23 from each parent)
5. Next Steps: Begins rapid cell division (mitosis)

How are chromosomes, DNA, and genes related?

1. Chromosomes: Threadlike structures carrying genetic material (46 total)
2. DNA: Molecule that makes up chromosomes; contains instructions for development
3. Genes: Segments of DNA that code for specific traits (eye color, height, etc.)
4. Inheritance: Genes are passed from parents to child and influence development

What is the Germinal stage of prenatal development?

1. Timeframe: First 2 weeks after fertilization
2. Key Events:
   • Zygote divides rapidly to form a blastocyst
   • Blastocyst implants into uterine wall
   • Placenta, umbilical cord, and amniotic sac begin forming
3. Risk: High risk of loss if implantation fails

What happens during the Embryonic stage of prenatal development?

1. Timeframe: Weeks 3 to 8
2. Key Events:
   • Major organs and body systems begin forming (organogenesis)
   • Heart starts beating
   • Limb buds and facial features form
3. Sensitivity: Extremely sensitive to teratogens
4. Loss: Most miscarriages due to abnormalities happen here

What are the three principles of prenatal development?

1. Cephalocaudal: Development from head to toe
2. Proximodistal: Development from the center of the body outward
3. Critical periods: Certain times are more sensitive to environmental influences

What occurs during the Fetal stage of prenatal development?

1. Timeframe: Week 9 to birth
2. Key Events:
   • Growth and refinement of organs
   • Bones harden and movement increases
   • Brain develops rapidly
3. Outcome: Viability increases with age

What is the age of viability?

1. Definition: The earliest age a fetus can survive outside the womb
2. Timeframe: Around 22 to 24 weeks, depending on medical care
3. Prognosis: Survival chances increase with each additional week

How is pregnancy described by trimesters for the mother?

1. First trimester (0 to 12 weeks): Fatigue, nausea, hormonal changes; emotional fluctuations common
2. Second trimester (13 to 26 weeks): Increased energy; fetal movement felt; body visibly changes
3. Third trimester (27 to birth): Discomfort, back pain, shortness of breath; anxiety about labor and delivery

What two forces shape a woman’s emotions during pregnancy?

1. Hormonal changes: Biological shifts impacting mood
2. Psychological factors: Stress, expectations, and the support system available

What are the effects of pregnancy on dads?

1. Emotional: Changes such as anxiety and excitement
2. Responsibility: Increased feelings of responsibility
3. Couvade syndrome: Experience of sympathy symptoms
4. Social: Relationship adjustments

What are teratogens?

1. Definition: Environmental agents that can harm prenatal development
2. Examples: Alcohol, drugs, nicotine, infections, and radiation
3. Variables: Effects depend on timing, dose, and genetics

What are the basic teratogenic principles?

1. Genetic vulnerability: Impact depends on the individual's genetic makeup
2. Developmental timing: Effects vary based on when the exposure occurs
3. Dose-response: Greater exposure equals greater damage
4. Outcomes: Can cause physical, cognitive, or behavioral issues

What are the effects of smoking during pregnancy?

• Low birth weight
• Premature birth
• Reduced oxygen supply
• Increased risk of SIDS (Sudden Infant Death Syndrome)
• Long-term learning and behavior problems

What are the effects of alcohol during pregnancy?

• Can cause Fetal Alcohol Spectrum Disorders (FASD)
• Facial abnormalities
• Brain damage
• Learning, memory, and attention problems
• Safety: There is no known safe amount of alcohol

What are the measurement issues in studying teratogens?

• Difficult to isolate one specific cause
• Ethical limits on experimentation (cannot intentionally expose humans)
• Reliance on self-reporting
• Many outcomes (sleeper effects) appear later in life

What is fetal programming research?

1. Definition: The theory that the prenatal environment can \"program\" long-term health
2. Environmental factors: Poor nutrition or stress may increase adult disease risk
3. Implication: Supports the extreme importance of prenatal care

What are common chromosomal problems in prenatal development?

1. Down syndrome (Trisomy 21): Extra chromosome 21
2. Turner syndrome: Missing X chromosome (XO)
3. Klinefelter syndrome: Extra X chromosome (XXY)
4. Cause: Errors during cell division

What are common genetic disorders in prenatal development?

• Single-gene disorders: Can be autosomal dominant or recessive
• Examples:
  • Cystic fibrosis
  • Sickle-cell anemia
  • PKU (Phenylketonuria)

What are the common prenatal tests?

1. Ultrasound: Visual imaging of the fetus
2. Amniocentesis: Testing of the amniotic fluid
3. Chorionic villus sampling (CVS): Testing of placental tissue
4. Purpose: Used to detect genetic or chromosomal disorders

How is infertility defined and caused?

1. Definition: Inability to conceive after 12 months of unprotected sex
2. Factors: Can affect males, females, or both
3. Causes: Hormonal issues, age, lifestyle, and genetics

What are Assisted Reproductive Technologies (ART)?

• IVF (In vitro fertilization): Egg and sperm combined in a lab
• Artificial insemination: Sperm placed directly into reproductive tract
• ICSI: Single sperm injected into an egg
• Considerations: Helps couples conceive but raises ethical and medical questions

What are the three stages of birth?

1. Labor: Contractions begin and the cervix dilates
2. Delivery: The baby is born/pushed out
3. Afterbirth: The placenta is expelled

What are the major threats to the baby during birth?

• Oxygen deprivation (hypoxia/anoxia)
• Premature birth
• Birth trauma
• Infection

What are the history and trends of childbirth?

• Shift from home births to hospital settings
• Increased medical intervention (e.g., epidurals)
• Rise in C-sections
• Growing interest in midwives and natural birth methods

What is the Apgar scale?

1. Purpose: Assesses newborn health at 1 and 5 minutes after birth
2. Measures: Heart rate, respiration, muscle tone, reflexes, and color
3. Scoring: Scores range from 0 to 10

What are the effects of low birth weight?

• Higher risk of illness and death
• Developmental delays
• Learning and behavioral problems later in life

What is the infant mortality trend?

1. Overall: General decline due to medical advances
2. Disparity: Still higher in disadvantaged populations
3. Links: Closely tied to prenatal care, socioeconomic status (SES), and access to healthcare