Breast pump

A breast pump is a mechanical device that extracts milk from the breasts of a lactating woman. Breast pumps may be manual devices powered by hand or foot movements or electrical devices powered by batteries or electricity from the grid.

On June 20, 1854, the United States Patent Office issued Patent No. 11,135 to O.H. Needham for a breast pump.Scientific American (1863) credits L.O. Colbin as the inventor and patent applicant of a breast pump. In 1921-23, engineer and chess master Edward Lasker produced a mechanical breast pump that imitated an infant's sucking action and was regarded by physicians as a marked improvement on existing hand-operated breast pumps, which failed to remove all the milk from the breast. The U.S. Patent Office issued U.S. Patent 1,644,257 for Lasker's breast pump. In 1956 Einar Egnell published his groundbreaking work, "Viewpoints on what happens mechanically in the female breast during various methods of milk collection". This article provided insight to the technical aspects of milk extraction from the breast. The Egnell SMB breastpump designed through this research is quite robust and many pumps are still in operation today over 50 years after publication.

Archaeologists working at a glass factory site in Philadelphia, Pennsylvania, excavated a 19th-century breast pipe that matches breast pumping instruments in period advertisements.

Mechanically, a breast pump is analogous to a milking machine used in commercial dairy production. A misconception is that the breast pump suctions milk out of the breast. A breast pump's job is to trigger the milk ejection response or letdown. Pumps achieve this by using suction to pull the nipple into the tunnel of the breast shield or flange, then release, which counts as one cycle. Thirty to sixty cycles per minute can be expected with better-quality electric breast pumps. The breast pump is not as efficient at removing milk from the breast as most nursing babies. Most manufacturers have multiple sizes of nipple tunnels available. These tunnels range in size from 24mm to 36mm.

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