THC Drug Test. A marijuana drug test is the technical analysis of a biological specimen, such as urine, blood, hair, sweat or saliva, to determine the presence or absence of the active ingredients of marijuana (mainly THC) or its metabolites (breakdown products).t is important to note that urine tests are usually conducted to test for the presence of THC metabolites which indicates marijuana use. Blood tests are conducted when the amount of THC still present in the system has to be ascertained.
How is my due date calculated? Your due date is calculated by adding 280 days (40 weeks) to the first day of your last menstrual period (assuming a 28 day cycle). Note that your menstrual period and ovulation are counted as the first two weeks of pregnancy. If you deliver on your due date, your baby is actually only 38 weeks old, not 40.
Use the Pregnancy Calculator to: 1  Determine the due date. 2  Calculate the likely conception date. 3  Calculate the end of the first and second trimesters. 4  Find out for how many weeks have you been pregnant. 5  Estimate the fetal age. 6  Calculate how many weeks you will be pregnant on a given date. Sperm lives for about 2 days. Because of the uncertainly of the exact conception date, obstetricians prefer to calculate the fetal age from the first day of the last menstrual cycle.