PIP: Abortion statistics are flawed by the lack of consistency in reporting gestational age. Several methods are generally used, and the number of abortions occurring before 12 weeks changes considerably depending upon the method used to determine gestational age. Pregnancy can be measured from the beginning of last menstruation or from fertilization, which is 14 days after the 1st day of the last menstrual period. Neither method accurately records pregnancy as determined by specialists in embryology and fetal development. Pregnancy actually begins with implantation, which begins 6-7 days after fertilization and ends 10-14 days later. Completion of fertilization and implantation occurs as much as 28 days after the 1st day of the last menstrual period. A report of an 8-week pregnancy is actually 6 weeks from fertilization and 4-5 weeks from implantation. The Centers for Disease Control and other abortion data collecting agencies use the 1st day of the last menstrual period. Statistics generally show that 50% of abortions occur before 8 weeks of gestation and 90% by 12 weeks. When gestation is considered at fertilization, 78% of abortions occur under 9 weeks, while 52% of abortions under 9 weeks are performed with data beginning at the 1st day of the last menstrual period. For abortions occurring under 12 weeks, 95% beginning at fertilization and 90% occur at the 1st day of the last menstrual period. 2/1000 vs. 5/1000 abortions occur under 20 weeks for data beginning at fertilization vs. at the onset of the last period. It is important to report abortion data accurately and to specify the method used to determine the gestational time period.