Labour and delivery Flashcards
Of the four phases of parturition, phase 2 is characterized by which of the following?
a. Uterine activation, cervical ripening
b. Uterine quiescence, cervical softening
c. Uterine involution, cervical remodelling
d. Uterine contraction, cervical dilatation
a
Cervical softening in phase 1 of parturition results in part from which of the following?
a. Stromal atrophy
b. Increased stromal vascularity
c. Increased collagen monomer cross-linking
d. all of the above
b. Increased stromal vascularity
Contraction-associated proteins (CAPs) within uterine smooth muscle prepare it to contract during labor. CAP concentrations increase during phase 2 of parurition and include all EXCEPT which of the following proteins?
a. connexin 43
b. oxytocin receptor
c. progesterone receptor A
d. prostaglandin F receptor
c. progesterone receptor A
Compared with the uterine body, the cervix has a significantly lower percentage of which of the following?
a. collagen
b. proteoglycans
c. smooth muscle
d. glycosaminoglycans
c. smooth muscle
All EXCEPT which of the following mechanisms lead in part to the cervical ripening that is characteristic of phase 2 of parturition?
a. decreased collagen fibril diameter
b. increased spacing between collagen fibrils
c. Altered levels of decorin and biglycan, which are proteoglycans
d. Increased expression of the enzymes responsible for synthesis of hyaluronan, which is a glycosaminoglycan
a. decreased collagen fibril diameter
- Which of the following best defines the Ferguson reflex?
a. mechanical stretch of the cervix enhances uterine activity
b. maternal ambulation augments contraction intensity and frequency
c. fetal scalp stimulation leads to fetal heart rate acceleration
d. maternal shifting to the left lateral recumbent position increases venous return
a. mechanical stretch of the cervix enhances uterine activity
- Extreme development of both upper and lower uterine segments may be seen with obstructed labour and clinically may be reflected by which of the following?
a. Hegar sign
b. Bandl ring
c. Bloody show
d. Chadwick sign
b. Bandl ring
- There are stresses on the pelvic floor caused by fetal head delivery during phase 3 of parturition. All EXCEPT which is true?
a. The anus may dilate up to 3cm
b. The perineal body becomes attenuated
c. The puborectalis muscle is markedly stretched
d. The coccygeus muscle receive the bulk of expulsive forces
d. The coccygeus muscle receive the bulk of expulsive forces
- Which of the following can bring about myometrial contractions?
a. extracellular magnesium
b. actin-tubulin protein pairs
c. G-protein coupled receptors
d. Gap junctions composed of decorin subunits
c. G-protein coupled receptors
- There are stresses on the pelvic floor caused by fetal head delivery during phase 3 of parturition. All EXCEPT which is true?
a. The anus may dilate up to 3cm
b. The perineal body becomes attenuated
c. The puborectalis muscle is markedly stretched
d. The coccygeus muscle receive the bulk of expulsive forces
d. The coccygeus muscle receive the bulk of expulsive forces
b. prolonged gestation
- Which of the following can bring about myometrial contractions?
a. extracellular magnesium
b. actin-tubulin protein pairs
c. G-protein coupled receptors
d. Gap junctions composed of decorin subunits
. G-protein coupled receptors
Once bound to its receptor, oxytocin promotes contraction through which of the following mechanisms?
a. opens calcium channels
b. generates nitric oxide
c. degrades 15- hydroxyprostaglandin dehydrogenase
d. activates the gene promotor region of the myosin light-chain kinase gene
a. opens calcium channels
In many mammals, suspension of the quiescence seen in phase 2 of parturition is due to which of the following?
a. cortisol withdrawal
b. progesterone withdrawal
c. inflammatory cell activation
d. increased oxytocin receptor concentration
b. progesterone withdrawal
For women with a prior preterm birth delivered at <37 weeks gestation, 17a-hydroxyprogesterone caproate may be used to prevent recurrent preterm birth. One mechanism by which progesterone maintains uterine quiescence is its ability to decrease expression of the which of the following?
a. Adenyl cyclase
b. Progesterone receptor A
c. Progesterone receptor B
d. Contraction- associated proteins.
d. Contraction- associated proteins.
Your patient presents at 39 weeks gestation with a breech-presenting fetus. After a discussion of the risks and benefits, she agrees to an ECV. Prior to initiation, you administer 0.25mg of terbutline s/c. This drug binds to beta-adrenergic receptors to create which of the following cellular responses to cause uterine relaxation?
a. Increased extracellular Mg2+ levels
b. Increased Intracellular Ca2+ levels
c. Increased cyclic adenosine monophosphate (cAMP) levels
d. Decreased cyclic guanosine monophosphate (cGMP) levels
c, Increased cyclic adenosine monophosphate (cAMP) levels
hCG shares the exact same receptor with which of the following hormones? Because of this, the high hCG levels seen with complete hydatifrom moles may lead to ovarian stimulation and formation of the theca-lutein cysts.
a. LH
b. TSH
c. FSH
d. none of the above
a. LH
Indomethacin, a NSAID, has some tocolytic actions. As a group, NSAIDS target which enzyme in prostaglandin production?
a. cyclooxygenase-1
b. Phosphlipase A2
c. Prostaglandin isomerase
d. prostaglandin dehydrogenase
a. cyclooxygenase-1