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What is The first centres of ossification appears during which month of pregnancy and explain in detail?
A i.e. At the end of 2nd month of pregnancy Clavicle is the first bone in the body to sta ossifying and is ossified from 3 centres. The shaft of clavicle is ossified from 2 (medical & lateral) primary centres, which appear between the 5th & 6", weeks of intra uterine life, and fuse about the 45th day meeting between the middle and lateral third of clavicle. A secondary centre for sternal end (and sometimes for acromial end) appears in late teens or early twenties