Clinical weeks of pregnancy are calculated as 1 month for every 4 weeks, i.e. 4 weeks of pregnancy is 1st month of pregnancy, 8 weeks of pregnancy is 2nd month of pregnancy, 12 weeks of pregnancy is 3rd month of pregnancy and so on. Clinical pregnancy is counted from the first day of the last menstrual period, with every 7 days counting as 1 week and every 4 weeks counting as 1 month. Therefore, 4 weeks of pregnancy is the 1st month of pregnancy, 8 weeks of pregnancy is the 2nd month of pregnancy, 12 weeks of pregnancy is the 3rd month of pregnancy, 16 weeks of pregnancy is the 4th month of pregnancy, 20 weeks of pregnancy is the 5th month of pregnancy, 24 weeks of pregnancy is the 6th month of pregnancy, 28 weeks of pregnancy is the 7th month of pregnancy, 32 weeks of pregnancy is the 8th month of pregnancy, 36 weeks of pregnancy is the 9th month of pregnancy, and 40 weeks of pregnancy is the 10th month of pregnancy. Full-term pregnancy is 37 weeks of pregnancy – 42 weeks of pregnancy, more than 42 weeks of pregnancy without delivery is called a premature birth, the pregnancy reaches 28 weeks but less than 37 weeks of birth is called a preterm birth.