Many birth-control pills release a constant amount of synthetic estradiols and progesterone for 21 days, followed by 7 days when no hormones are ingested. which of the following statements most accurately describes the effects of birth-control pills? birth-control pills maintain constant levels of estrogens and/or progesterones and mask the release of the oocyte from the follicle. birth-control pills maintain constant levels of estrogens and/or progesterone so there is no surge in lh and ovulation does not occur. birth-control pills inhibit the development of the uterine lining so implantation of a fertilized oocyte cannot occur. the 7 days with no hormones does not allow a thick enough uterine lining to form so a fertilized oocyte cannot implant.