How do the emergency contraceptive pills Plan B and Ella differ?
a. Plan B contains progestin; Ella contains ulipristal acetate.
b. Plan B contains ulipristal acetate; Ella contains progestin.
c. Plan B contains estrogen; Ella contains progestin.
d. Plan B contains progestin; Ella contains estrogen.
Question 2
What is thought to be the main mechanism of action of emergency contraceptive pills?
a. impairing a fertilized egg from implanting in the uterus
b. inhibition of ovulation
c. breaking apart the sperm's flagella
d. blockage of the fallopian tubes