CC Ādi 13.80
jagannātha-śacīra dehe kṛṣṇera praveśe
Lord Caitanya Mahāprabhu took His birth in the year 1407 Śaka Era (A.D. 1486), in the month of Phālguna. But here we see that He entered the bodies of His parents in the year 1406, in the month of Māgha. Therefore, the Lord entered the bodies of His parents thirteen full months before His birth. Generally a common child remains within the womb of his mother for ten lunar months, but here we see that the Lord remained within the body of His mother for thirteen months.