As soon as a child was born it was washed, and rubbed with salt (Ezek. 16:4), and then swathed with bandages (Job 38:9; Luke 2:7, 12). A Hebrew mother remained forty days in seclusion after the birth of a son, and after the birth of a daughter double that number of days. At the close of that period she entered into the tabernacle or temple and offered up a sacrifice of purification (Lev. 12:1-8; Luke 2:22). A son was circumcised on the eighth day after his birth, being thereby consecrated to God (Gen. 17:10-12; comp. Rom. 4:11). Seasons of misfortune are likened to the pains of a woman in travail, and seasons of prosperity to the joy that succeeds child-birth (Isa. 13:8; Jer. 4:31; John 16:21, 22). The natural birth is referred to as the emblem of the new birth (John 3:3-8; Gal. 6:15; Titus 3:5, etc.).
–Easton's Bible Dictionary