Jaymie Ticknor Developmental Psychology 3620 Sect 853 19 September 2013 Chapter 5 Prenatal Development Birth and the Newborn Fertilization the moment a sperm unites with an egg in this process Zygote fertilized egg Prenatal Development The Three Stages of Prenatal Development Ovum unfertilized egg Ovulation release of a mature egg from an ovary Sperm that have a Y chromosome are lighter and can swim faster and are more likely to reach the egg first more vulnerable weaker and smaller so fewer male conceptions survive Gestational Age the length of time since the conception of a developing organism The Germinal Stage Conception to 2 Weeks Germinal Stage the prenatal stage that lasts from conception to 2 weeks postconception Begins when the sperm penetrates the egg once fertilization occurs and a zygote has been created the outside of the egg thickens so that no other sperm will be able to enter The zygote goes through the fallopian tube where cell division begins 5 days after conception the mass of cells is ready to implant into the lining of the Blastocyst a hollow ball of cells that consists of the inner cell mass which becomes the embryo and an outer ring of cells which becomes the placenta and chorion Inner Cell Mass a solid clump of cells in the blastocyst which later develops into the uterus embryo Trophoblast the outer ring of cells in the blastocyst that later develops into the support system for the pregnancy cells inside secrete an enzyme that digests some of the lining in the uterus so that the blastocyst can securely embed itself there after implantation fingerlike extensions from the outer layer of the trophoblast grow into the uterus and a connection between the embryo and the mother is established Infertility Infertility the inability to conceive within 1 year of frequent unprotected sex The Embryonic Stage 2 Weeks to 2 Months Embryonic Stage the prenatal stage that lasts from 2 weeks to 2 months postconception Embryo the developing organism from conception to the end of the second month of pregnancy The support system for the pregnancy includes two fetal membranes sacs one inside the other as well as the placenta and umbilical cord Chorion the outer fetal membrane that surrounds the fetus and gives rise to the placenta Amnion the inner fetal membrane that surrounds the fetus and is filled with amniotic fluid to cushion and protect the fetus during development Placenta the organ that supports a pregnancy by bringing oxygen and nutrients to embryo from the mother through the umbilical cord and carrying away fetal waste products Fetus the developing organism from the end of the eighth week postconception until birth Ectoderm the outermost layer of the inner cell mass that later becomes the skin sense organs Endoderm the innermost layer of the inner cell mass that later becomes the respiratory system brain and spinal cord digestive system liver and pancreas Mesoderm the middle layer of the inner cell mass that later becomes the muscles bones blood Organogenesis the process in prenatal development by which all of the major organ systems of Cephalocaudal Development a principle whereby development proceeds from the head region heart kidney and gonads the body are laid down down through the body Critical Period a period of time during which development is occurring rapidly and the organism is especially sensitive to damage which often is severe and irreversible The Fetal Stage Fetal Stage the prenatal stage that lasts from 2 months postconception until birth Health and Risks in Pregnancy Three Trimesters of Pregnancy First Trimester may not be apparent to other people that the woman is pregnant but changes in the level of her hormones may cause certain effects fatigue breast tenderness and morning sickness nausea that often subsides as the day progresses Second Trimester pregnancy becomes apparent as the fetus grows larger woman is able to feel the fetus moving inside of her called the quickening Third Trimester fetus continues to grow woman becomes more tired and uncomfortable she will experience the fetus dropping lower within her as it begins to get into position to begin the birth process Couvade a sympathetic pregnancy in which a man experiences a variety of symptoms associated with pregnancy or childbirth while his partner is pregnant The Expectant Father Miscarriage the natural loss of a pregnancy before the fetus reaches a gestational age of 20 weeks Miscarriage Teratogens Teratogens agents that can disrupt prenatal development and cause malformations or termination of the pregnancy Alcohol and Smoking Fetal Alcohol Syndrome FAS a condition in the child resulting from heavy or binge consumption of alcohol during a pregnancy associated with characteristics facial features small stature and a small head as well as cognitive deficits and trouble controlling behavior and regulating emotions Fetal Alcohol Spectrum Disorders FASD a range of impairments in a child resulting from consumption of alcohol during pregnancy associated with any subset of characteristics of fetal alcohol syndrome at varying levels of severity and other more subtle or functional deficits The Birth Experience Labor and Delivery Early Labor the first phase in the first stage of labor in which contractions are usually not painful but the cervix begins to thin out efface and dilate open up Active Labor the second phase in the first stage of labor in which contractions become longer stronger and more frequent and the cervix dilates to 4 centimeters Transition the third phase in the first stage of labor in which contractions come in rapid succession and last up to 90 seconds each with little or no pause between them and which ends when the cervix has dilated 10 centimeters Doula a trained knowledgeable companion who is present at a birth to support the woman through her labor and delivery The Birth Experience of the Baby Apgar Scale an assessment of a newborn s overall condition at 1 minute and 5 minutes after birth that is based on the newborn s activity level pulse grimace appearance and respiration Birthing Options Professionals The Newborn Infant States Infant States different levels of consciousness used to regulate the amount of stimulation an infant receives states range from crying to deep sleep Quiet Alertness when awake the eyes are open and the baby is attentive to what is going on around him her but he she is very still Active Alertness the baby is alert to what is going on in his her