Inducing Labor Flashcards
While the exact mechanisms that induce labor remain a mystery, cervical ripening is a known predecessor. What changes facilitate this?
Collagen breaks down and alters the amount of glycoamines, stimulating water retention. Oxytocin receptors in the myometrium increase, and gap junctions enlarge between cells, improving contraction responses to oytocin and prostaglandins
What are the indications for elective induction of labor?
pre-eclampsia/eclampsia
maternal DM
premature rupture of membranes
chioamnionitis
intrauterine fetal growth restriction
fetal demise
postterm pregnancy
T or F. Fetal macrosomia is an indication for labor induction
F. No increased risk to baby or mom (but it does raise the risk for caecarian birth)
What are some contraindications of labor induction?
active genital herpes infection
umbilical cord prolapse
fetal malpresentation
The _____ score is the accepted method for assigning cervical ripening, the most important predictor of the success of labor induction
Bishop
What is the most common drug for labor induction?
Oxytocin
What is the most common complication of oxytocin administration (pitocin)?
uterine hyperstimulation that can predispose to postpartum hemorrhage, which is generally reversed by discontinuing the drug due to its short half-life
It also has antidiuretic effects leading to water intoxication and hyponatremia
How do prostaglandins work in pregnancy?
blocking progesterone and causing a local inflammatory response and cervical ripening
What preparations of prostaglandins are most commonly used for labor induction?
- Dinoprostone
- Prepidil gel
- Misoprostol
T or F. A ripened cervic is more receptive to oxytocin stimulation, requires a lower dose of oxytocin, and has been shown to need fewer serial inductions
T.
What are the most common herbs/supplements used for labor induction/augmentation?
castor oil
blue and black cohosh
How does blue cohosh promote labor induction?
It has oxytoxic effects
How does black cohosh promote labor induction?
It exerts estrogenic effects and is used for cervical ripening. Ten drops under the tongue is the dosage that has been known to have a noticeable effect on the cervix within an hour.
It can act as a vasodilatory and is generally not recommended for use in pregnancy due to its abortifacient properties
Why has sexual intercourse been thought to stimulate labor?
It can stimulate uterine contractions because of prostaglandins in semen and because of the physical stimulation of contractions after orgasm
Other mechanical ways to induce labor?
Nipple stimulation causes secretion of endogenous oxytocin
Stripping or sweeping the membranes, cervical dilators, and extra-amnionic saline infusions can stimulate prostaglandin secretion andor manually dilate the cervix
