Pregnancy Flashcards
Durations of the Pregnancy Trimesters
First Trimester: Last Menstrual period to Week 12
Second Trimester: Weeks 13 to 27
Third Trimester: Weeks 28 to 40
First Trimester
Weeks 3-8 is called …
embryonic period
First Trimester
Week 9 until delivery is called …
fetal period
First Trimester
Major event of Week 10
Placenta Formation
First Trimester
During Week 10, the Placenta takes over …
Progesterone Production
First Trimester
What develops during First Trimester
Organ Systems of Embryo
First Trimester
What may occur due to toxic exposure during Organ Development?
Congenital Abnormalities
First Trimester
What happens to the Uterus during the First Trimester?
Enlarges and softens
First Trimester
Complications
Ectopic Pregnancy
Mother-To-Child Transmission (MTCT)
Spontaenous Abortion/Miscarriage
First Trimester
Examples of MTCT
Congenital Rubella Syndrome
Congenital Syphilis
Congenital HIV
Congenital Hepatitis B
Second Trimester
Characteristics of fetus
Reaches Viability
Can survive outside the womb
Second Trimester
Characteristics of Uterus
Expands into abdomen
Quickening
Second Trimester
What is Quickening?
Woman becomes aware of fetal movements at 20 weeks
Second Trimester
Morning Sickness
Effects recede as β-hCG concentration levels off
β-hCG is produced by Placenta and causes Morning Sickness symptoms
Second Trimester
Complications
Gestational Diabetes Mellitus
Hemolytic Disease of Fetus/Newborn
Third Trimester
Characteristics of fetus
Fully formed and can survive outside womb
Third Trimester
Which organs are not fully developed at this point?
Lungs (which is completed at 36 weeks)
Third Trimester
Why may patients feel uncomfortable during this trimester?
Weight of Uterus and Contents
Esophageal Reflux
Edema
Venous Congestion causing Hemorrhoids and Low Extermity Varicosities
Third Trimester
Complications
Preterm Labor (less than 37 weeks)
Relative Surfactant Deficiency causes Respiratory Distress Syndrome in Premature Babies
Preeclampsia (high b.p. during pregnancy causing systemic vasoconstriction)
Function of Placenta
Transfer:
Oxygen
Nutrients
Carbon Dioxide
Fetal Waste Products
Which hormones are secreted by Placenta?
Progesterone
Estrogen
Relaxin
β-hCG
Human Placental Lactogen
Corticotropin-Releasing Hormones
Where is Human Placental Lactogen produced?
Syncytiotrophoblast Cells
Function of Human Placental Lactogen
Ensures fetus has Adequate Nutrition
How does Human Placental Lactogen ensure that fetus has adequate nutrition?
Alters Mother’s metabolism including:
Increased glucose levels
Lowers glucose utilization
Increasing lipolysis
Where is Corticotropic-Releasing Hormone produced?
Syncytiotrophoblast
Functions of Corticotropic-Releasing Hormone
Prostaglandin Production
Increasing DHEA Levels
Uterine Contractions (at term)
Regulation of Placental Blood Flow
Placental Gaseous Transport Process
Fill out the following about Nutrient Transport through Placenta
How is the Fetus protected from Maternal Immune Responses?
Altered HLA Expression
Fas Ligand
Placental Indoleamine 2,3-Dioxygenase (IDO)
Altered HLA Expression
Definition
Atypical HLA-G cell-surface proteins
Altered HLA Expression
Function
Interact with mother’s Natural Killer Cells and Cytotoxic T Cells
Altered HLA Expression
Where are they produced?
Trophoblast
Fas Ligand
Function
Fas Ligand interacts with Fas Receptor on Maternal Lymphocytes causing Apoptosis
Fas Ligand
Where are they produced?
Trophoblast Cells
PlacentalIndoleamine-2,3-Dioxygenase(IDO)
Function
Degrades Typtophan into Kynurenine
PlacentalIndoleamine-2,3-Dioxygenase(IDO)
Purpose of Typtophan Degradation
Maternal T Cels require Tryptophan for survival
Kynurenine inhibits T-cell development and survival
PlacentalIndoleamine-2,3-Dioxygenase(IDO)
Location of production
Placental Blastocyst
What triggers passive immunity in the fetus?
Maternal IgG passes through placenta during Last Trimester of Pregnancy
Lasts for several months
How does IgG cross the placenta?
Taken up by Endocytosis
Bind to intracellular Fc receptors
Transport IgG to fetal side of Placenta
