Chapter 4: Prenatal Development and Birth

germinal period

the first two weeks of prenatal development after conception, characterized by rapid cell division and the beginning of cell differentiation

embryonic period

the stage of prnatal development from approximately the third through the eighth week after conception, during which the basic forms of all body structures, including internal organs, develop

fetal period

the stage of prenatal development from the ninth week after conception until birth, during which the organs grow in size and mature in functioning

blastocyst

a cell mass that develops from the zygot in the first few days after conception, during the germinal period, and forms a hollow sphere in preparation for implantation

placenta

the organ that surrounds the developing embryo and fetus sustaining life via the umbilical cord. the __ is attached to the wall of the uterus

implantation

the process, beginning about 10 days afte conception, in which developing organism burrows into the placenta that lines the uterus where it can be nourished and protected as it continues to develop

embryo

the name for developing organism from about the third through the eight week after conception

fetus

the name for a developing organism from the ninth week after conception until birth

age of viability

the age (about 22 weeks after conception) at which ta fetus might survive ouside the mother's uterus if specialized medical care is available

teratogens

Agents and conditons including viruses, drugs, and chemicals that can impir prenatal development and result in birth defects or even death

behavioral teratogens

agents and conditions that can harm the prenatal brain, impairing the future child's intellectual and emotional functioning

risk analysis

the sicence of weighing the potential effects of a particular even substance of experience to determne the likelihood of harm. In teratology, ____ attempts to evaluate everything that affects the chances that a particular agen or condition will cause damage to an embryo or fetus

critical period

in prenatal development, the time when a particular organ or other body part of the embryo or fetus is most susceptible to damage by teratogens

threshold effect

a situation in which a certain teratogen is relatively harmless in small doses but becomes harmful once exposure reaches a certain level (threshold)

fetal alcohol syndrome (FAS)

A cluster of birth defect, including abnormal facial characteristics, slow physical growth, and retarded mental development, caused by the mother's drinking alcohol while pregnant

apgar scale

A quick assessment of a neborn's body functioning. The baby's color, heart rate, reflexes, muscle tone, and respiratory effort are given a score 0,1, or twice at one minute and five minutes after birth and the total of all the scores is compared with the ideal score of 10

cesarean section

a surgical birth in which incisions through the mother's abdomen and uterus allow the fetus to be removed quickly, instead of being delivered through the vagina

doula

a woman who helps with the birth process. Traditionally in Latin America, was like a midwife, the only professional who attended childbirths. Now ___are likely to work alongside hospital's medical staff to help mothers through labor and delivery

anoxia

a lack of oxygen that, if prolonged during birth, can cause brain damage or death to the baby

cerebral palsy

a disorder that results from damage to the brains's motor centers. people with cerbral palsy have difficulty with muscle control, so their speech and body movements are impaired

low birthweight (LBW)

a body weight at birth of less than 5 1/2 pounds

very low birhweight (VLBW)

a body weight at birth of less than 3 pounds 5 ounces

extremely low birthweight (ELBW)

a body weight at birth of less than 2 pounds 3 ounces

preterm birth

a birth that occurs three or more weeks before the full 38 weeks of the typcical pregancy has elapsed. 35 or fewer weeks after conception

small for gestational age (SGA)

a term for a baby whose birthweight is significantly lower than expected, given the time since conception. ex 5 pound nebors is considered SGA if born on time but not SGA if born two months early

kangaroo care

a form of child care in which the mother of a low-birthweight infant spends at least an hour a day holding the baby beween her breasts, like a kagaroo that carries her immature newborn in a pouch on her abdomen

parental alliance

cooperation between a mother and father based o their mutual commitment to their children. I a parental alliance, the parents agree to support each other in their shared parental roles

postpartum depression

a new mother's feelings of inadequacy and sadness in the days and weeks after giving birth

parent-infant bond

the strong, loving connection that forms as parents hold their newborn

interaction affect

the result of a combination of teratogens. sometimes risk is greatly magnified when an embryo or fetus is exposed to more than on teratogen at the same time

gravid

number of pregnancys

parity

number of children living