It is possible for eggs to still release and fertilization to occur. In theory, the hormone combination from the pill prevents the [[ovum]] from attaching to the [[uterus|uterine lining]], and therefore does not allow the normal cycle of [[pregnancy]] to commence. However, in 4-15% of fertilizations, implantation of the ovum actually does occur, and the pill induces early escape ovulation.<ref>http://www.prolife.com/BIRTHCNT.html</ref> Thus, women who use birth control pills for extended periods of time while sexually active are mathematically almost guaranteed at least one early chemical abortion, which has led to the birth control pill being nicknamed the "abortion" pill by some. | It is possible for eggs to still release and fertilization to occur. In theory, the hormone combination from the pill prevents the [[ovum]] from attaching to the [[uterus|uterine lining]], and therefore does not allow the normal cycle of [[pregnancy]] to commence. However, in 4-15% of fertilizations, implantation of the ovum actually does occur, and the pill induces early escape ovulation.<ref>http://www.prolife.com/BIRTHCNT.html</ref> Thus, women who use birth control pills for extended periods of time while sexually active are mathematically almost guaranteed at least one early chemical abortion, which has led to the birth control pill being nicknamed the "abortion" pill by some. |