Answer:
The cervical mucus is made resistant to penetration by spermatozoa.
Hormonal contraceptives inhibit the hypothalamic secretion of gonadotropin-releasing hormone, which inhibits FSH and LH. The drugs produce cervical mucus that resists penetration of spermatozoa into the upper reproductive tract. Hormonal contraceptives inhibit the release of follicle-stimulating hormone and luteinizing hormone. The drugs interfere with endometrial maturation and reception of ova that are released and fertilized.
Step-by-step explanation: