Parturition and Lactation
About this set
Created by:
abthomas2005 on December 1, 2011
Subjects:
Log in to favorite or report as inappropriate.
Order by
16 terms
Terms | Definitions |
|---|---|
 Mechanism of action of oxytocin | Gq receptors - increase contractility of uterine myometrium (increased amplitude/frequency) Supplemented by prostaglandins - contraction (Via PLC) or relaxation (via cAMP) |
| Uterine priming | Estrogen sensitizes the myometrium to oxytocin - increases gap junctions and number of receptors |
| Two theories of initiation of birthing | Increased estrogen/progesterone ratio Increased levels of CRH |
| Explain theory of increase estrogen/progesterone ratio |  |
| Explain theory of increased levels of CRH |  |
| Changes in uterine structure before birthing | Two distinct sections (upper muscular section - for propulsion; lower thinner section - allows for ripening of cervix and vagina) Increased number of oxytocin receptors |
| Positive feedback loop that leads to birthing |  |
| First stage of labor | Begins when uterine contractions are of sufficient freq, intensity and duration Latent phase: rate of cervical dilation is slow (up to 3cm) Active phase: rate of dilation is about 1cm/hr |
| Second stage of labor | Begins when dilation reaches 10cm. Fetal head begins descent (Friedman curve - fetal head in relation to ischial spine to assess progress of labor) |
| Third stage of labor | Interval between delivery of the fetus and delivery of the placenta During this stage the placenta separates and is expelled Typically takes 5-30 minutes Causes bleeding - but limited by continued uterine contractions (vasoconstriction/vasospasm) |
| Physiology of dystocia | Abnormally slow labor Can be cause by: uterus, size of the fetus, positioning of the fetus and excess sedation/anesthesia Cephalicopelvic disproportion - head is too big to fit through birth canal |
| Breast milk is good because: | - It is suitable for digestion by immature GIT - Provides optimal water/electrolytes - Immunological protection - Contains hormones (vitamin D, TRH, GnRH, etc) |
| Major hormones associated with lactation | - Estrogens, (progesterone, prolactin, hCS, cortisol, insulin, GH, and others) - Epithelial tissues expand and become activated - Estrogen and prolactin leads to deposition of fat tissues |
| Milk production inhibition in pregnancy | - High levels of estrogen (inhibits terminal differentiation) and progesterone (inhibits lactogenesis) - After birth, both drop dramatically |
| Prolactin and lactation | - Suckling inhibits DA and stimulates prolactin releasing factor - Therefore, suckling creates a prolactin spike - Needs multiple w/in 24-hours to sustain milk production |
| Oxytocin and lactation | - Allows milk to be ejected from the breast (milk let-down reflex) - Suckling leads to release (~1min delay) - Oxytocin contracts myoepithelial cells leads to breast milk release |
First Time Here?
Welcome to Quizlet, a fun, free place to study. Try these flashcards, find others to study, or make your own.