Last menstrual period

Last menstrual period: By convention, pregnancies are dated in weeks starting from the first day of a woman's last menstrual period (LMP). If her menstrual periods are regular and ovulation occurs on day 14 of her cycle, conception takes place about 2 weeks after her LMP. A woman is therefore considered to be 6 weeks pregnant 2 weeks after her firs...
Found on http://www.medterms.com/script/main/art.asp?articlekey=13608

Last Menstrual Period

The calendar date of a woman's last menstrual period before fertilization occured. This is the point in time from which the pregnancy is measured and the due date is calculated. Synonym(s): LMP
Found on http://www.pregnology.com/AZ/L/2
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