Prenatal Development Overview

Prenatal Development

• The prenatal period encompasses the germinal, embryonic, and fetal periods.
• The germinal period (first two weeks) involves rapid cell division and differentiation.
• The embryonic period (weeks 3-8) marks the development of basic body structures.
• The fetal period (weeks 9-birth) involves growth and maturation of the fetus.

The Germinal Period

• The zygote begins duplication and division shortly after conception.
• The placenta develops, providing nourishment and waste removal.
• Implantation occurs roughly 10 days after conception.
• The organism experiences rapid growth.

Embryonic Period

• A developing human organism emerges from the third through eighth week after conception.
• The primitive streak becomes the neural tube.
• Basic structures like the head, eyes, ears, and mouth form.
• Heartbeat commences, and limbs and fingers/toes develop.

Fetal Period

• The fetal period begins in the ninth week after conception and continues until birth.
• Sexual organs differentiate.
• Heartbeat is detectable via stethoscope.
• All body systems finalize development.
• The brain develops significantly; however, the cortex isn't fully mature.
• The brain at birth is larger than other body parts.

Age of Viability

• Approximately 22 weeks after conception represents the age of viability; newborns can potentially survive outside the womb with supportive care.

Birth

• Fetal brain triggers hormonal release stimulating uterine contractions.
• Labor duration varies, typically taking 12 hours for firstborns.
• The Apgar scale assesses the newborn's condition immediately after birth.

Traditional and Modern Birthing Practices

• Home births and hospital births represent common birthing practices.

Cesarean Section (C-Section)

• Surgical birth procedures enable quick fetus removal.
• Rates of C-sections vary based on factors like country, planned procedures, or emergencies.
• More sections take place in richer countries compared to poorer countries.
• C-sections may lead to long-term recovery issues, but often result in less trauma for the baby.

Medical Intervention

• Infant mortality rates have decreased due to enhanced medical care.
• Childbirth has become safer, but excessive intervention may pose disadvantages.

Low Birthweight

• Low birthweight (LBW) is defined as less than 2,500 grams or 5.5 pounds at birth.
• Very low birthweight (VLBW) is less than 1,500 grams (3.3 pounds).
• Extremely low birthweight (ELBW) is less than 1,000 grams (2.2 pounds).

Preterm or Slow Growing

• Preterm birth occurs before the 35th week of pregnancy.
• Small for gestational age (SGA) means the baby's weight is significantly lower than expected at birth.

Causes of Low Birthweight

• Genetic factors, maternal illness, exhaustion, infection, malnutrition, and drug use, as well as multiple births, are contributing factors impacting low birthweight.

Mothers, Fathers, and a Good Start

• Supporting fathers can positively impact the mother's and fetus's health.
• Fathers can either reduce or increase mother's stress levels.
• Fathers may play an essential role in infant care.
• Mother-father tandem involvement benefits the infant.

The Importance of Close Contact

• Birth complications can affect a child's wellbeing later in life.
• Early and consistent infant care are crucial.
• Kangaroo care, a beneficial technique, allows low-birthweight infants to feel their mother's body heat.

Postpartum Depression

• Postpartum depression involves sadness and inadequacy in the days and weeks after giving birth.
• Symptoms range from the baby blues to severe postpartum psychosis.
• Paternal involvement, and emotional support, can sometimes help lessen the effects of postpartum issues.

Bonding

• Parent-infant bonding creates a strong and loving connection during infant care.
• Skin-to-skin contact might not be essential for bonding, even though it's still beneficial.
• Cross-fostering studies in monkeys demonstrate that a strong and beneficial parent-infant relationship often manifests.

Nature, Nurture, and the Phenotype

• Four general research conclusions involve genetic and nongenetic influences, parental behaviors, and environmental influences.
• Genes impact almost every aspect of human behavior.
• Influences impact behavior from conception and continue throughout life, sometimes altering genetic instructions.
• The environment impacts the way parents handle parenting and raise children.
• Children choose niche environments that suit inherited traits.

Nearsightedness or Myopia

• Nearsightedness or myopia encompasses two types: high (severe) and low (less severe).
• Nearsightedness runs in families.
• Minor gene variations associated with nearsightedness, such as Pax6 gene variations, can be a contributing factor to nearsightedness.
• Environment plays a role in nearsightedness, environmental factors, and schoolwork may be contributing factors.

Alcoholism

• Alcoholism may have a genetic component that leads to addiction in specific individuals.
• Environmental factors can modify the genetic effects of alcoholism.
• Alcohol use during pregnancy risks Fetal Alcohol Syndrome (FAS).
• FAS involves issues like facial abnormalities, growth retardation, and developmental delays.

Prenatal Teratogens

• Teratogens are substances or conditions that potentially harm prenatal development.
• Not all are avoidable.
• Birth defects resulting from teratogens can be noticeable at birth, while behavioral effects may manifest later in life.
• Teratogens can impact a child's development, including leading to conditions like retardation, hyperactivity or learning disabilities.

Potential Genetic Counseling Issues

• Prospective parents may need genetic counseling to determine the genetic health risks for their child.
• False positives and negatives in genetic testing are significant issues.
• Genetic testing leads to further tests, and the results introduce additional emotional distress.