Endocrine Drugs and Medications Q 30
Which of the following is a contraindication for use of oxytocin to induce labor?
A. Missed abortion
B. Placenta previa
C. Hyperbilirubinemia
D. Pregnancy past due date
Correct Answer: B. Placenta previa
Use of oxytocin is contraindicated in the presence of placenta previa. Labor induction in this condition could be fatal to the fetus. Placenta previa is an indication for cesarean section. Specific contraindications to oxytocin include hypersensitivity to the hormone itself or any part of its synthetic version and vaginal deliveries that are in themselves contraindicated. These include the patient having an active genital herpes infection, vasa previa, complete placenta previa, invasive cervical cancer, and prolapse or presentation of the umbilical cord).
Option A: Oxytocin is indicated and approved by the FDA for two specific time frames in the obstetric world: antepartum and postpartum. In the antepartum period, exogenous oxytocin is FDA-approved for strengthening uterine contractions with the aim of successful vaginal delivery of the fetus. There are three situations during the antepartum period in which oxytocin is indicated for mothers who have preeclampsia, maternal diabetes, premature rupture of the membranes; for mothers with inactive uteri that require stimulation to start labor; and for mothers with inevitable or incomplete abortions in their second trimester.
Option C: Hypoosmolarity causes swelling of the red blood cells and makes them fragile and susceptible to hemolysis. Various studies have approved the effects of oxytocin on jaundice. Some studies have suggested that the extensive use of oxytocin in labor induction is one of the factors leading to neonatal jaundice
Option D: When oxytocin is released, it stimulates uterine contractions, and these uterine contractions, in turn, cause more oxytocin to be released; this is what causes the increase in both the intensity and frequency of contractions and enables a mother to carry out vaginal delivery completely. The head of the fetus pushes against the cervix, the nerve impulses from this action travel to the mother’s brain, which activates the posterior pituitary to secrete oxytocin. This oxytocin is then carried through the blood to the uterus to increase uterine contractions further, and the cycle continues until parturition.