Prenatal: Early Stages
The first stage of prenatal development, spanning from fertilization to the first two weeks of intrauterine life.
The germinal period
The longest stage of prenatal development, running from week 9 until birth.
The fetal period
The automatic sucking movement a newborn makes when an object is placed inside its mouth.
The sucking reflex
A startle response triggered by a loud noise or sudden loss of support, causing the baby to fling its arms out.
The Moro reflex
The sense that develops first prenatally and is the most mature sense at birth
Touch
A sphere-shaped structure formed shortly after conception that implants itself into the uterine wall.
The blastocyst
External agents such as drugs, chemicals, or infections that can cause birth defects during pregnancy.
Teratogens
A reflex where an infant turns its head and opens its mouth when its cheek is stroked.
The rooting reflex
A reflex where an infant's toes fan out when the sole of the foot is stroked from heel to toe.
The Babinski reflex
A clinical scale administered at one and five minutes after birth to evaluate a newborn's general health.
The Apgar scale
The outer germ layer of the embryo from which the nervous system and skin develop.
Ectoderm
A vital organ that forms during pregnancy to provide oxygen and nutrients to the fetus and eliminate waste.
The placenta
A reflex where an infant tightly curls its fingers around any object placed in its palm.
The palmar grasp reflex
Also known as the "fencer" posture, occurring when a baby turns its head to one side and extends that arm and leg.
Asymmetrical tonic neck reflex
The approximate visual distance range in inches where a newborn's eyes focus best to distinguish faces.
8 to 12 inches
The stage of prenatal development lasting from week 3 to week 8, where major organs and body structures form.
The embryonic period
A maternal habit or substance strongly associated with lower birth weight and developmental issues in infants.
Cigarette smoke
A reflex similar to the palmar grasp but located in the feet, causing toes to curl when the sole is stimulated.
The plantar grasp reflex
A reflex where the infant curves its torso toward the side that is lightly stroked along the spine.
The Galant reflex
The technical term for automatic, involuntary responses present at birth that disappear as the nervous system matures.
Primitive reflexes
The intermediate germ layer of the embryo that specifically gives rise to the circulatory, skeletal, and muscular systems.
Mesoderm
The approximate gestational window when the fetus achieves the ability to survive outside the womb with medical assistance.
24 weeks
A coordinated sequence of primitive oral motor responses that allow a newborn to extract milk and swallow safely
Sucking and swallowing reflexes
An involuntary protective response demonstrating neurological integration by assessing how the system reacts to temporary imbalance.
The Moro reflex
A specific auditory stimulus from the intrauterine environment that fetuses and newborns prefer over any other human voice.
The mother's voice