The Nurse Who Helped Build the Modern Breast Pump - And the Brand That Never Forgot Her
By 1939, the breast pump had existed in various forms for over two thousand years. Clay pots, glass sucking vessels, pipe devices, rubber bellows, mechanical motors. Each generation of inventors had improved on what came before.
But almost none of them had formally studied what actually happens inside the breast during milk expression. That was about to change.
The challenge
When war broke out in Europe in 1939, restrictions on inter-Atlantic trade left many overseas hospitals without a supply of replacement Abt Pumps and parts. It was then that a struggling Swedish engineer named Einar Egnell became intrigued by the prospect of building a better breast pump. He devoted three years to learning the mechanics of lactation and experimented with how best to mimic the nursing infant.
This was a different starting point from any previous inventor in this history. Egnell was not adapting a dairy machine or a bellows device or a glass sucking vessel. He was studying lactation itself - the physiology of how milk moves through the breast, what triggers letdown, what suction patterns feel tolerable versus damaging, and how the entire mechanical process could be made to work with the body rather than against it.
The collaboration
He went to the maternity hospital in Stockholm and worked with Sister Maja Kindberg, a nurse on the maternity ward. He worked so closely with her, in fact, that the pump was named for her.
Maja Kindberg was the head nurse at Sodersjukhuset hospital in Stockholm. Reportedly, Egnell went through eight prototypes before arriving at a design that earned Kindberg's and her patients' approval. This was not a theoretical exercise. Each version was tested on real mothers in a real maternity ward, with Kindberg gathering feedback and Egnell returning to his workshop to adjust. Eight times.
He asked lactating people what they needed, which was unusual at the time - a genuinely user-centered design process. In an era when breast pumps were designed by engineers and evaluated by physicians, the idea that the mothers themselves should determine whether a design was good enough was novel.
The idea that the mothers themselves should decide whether a design was good enough was, at the time, genuinely radical.
The pump
From the earliest days of its introduction, mothers at the Stockholm hospital began to demand what became called the Sister Maja Breast Pump - or SMB. The name was Egnell's acknowledgment that this pump would not exist without Kindberg's involvement. She was not a footnote in the story. She was a co-creator.
The SMB was the first truly hospital-grade electric breast pump. It was also, by the standards of the time, enormous. It weighed about 40 pounds. Given its heft and complexity, it was used almost exclusively in hospitals. But what it delivered in terms of safety, comfort, and effectiveness had never been achieved before.
The standards he set
From his research into breast physiology, Egnell established two benchmarks that became the foundation of breast pump safety evaluation: maximum vacuum pressure and cycling rate. These remain the two most important safety standards in the breast pump industry today. Every pump brought to market is still evaluated against the framework Egnell built in that Stockholm hospital.
Find your flange fit the way Egnell would have
He spent three years learning how the breast actually works before he trusted a design. Our free Flange Fit Guide helps you measure and size yours in a few minutes.
The brand that carried it forward
Einar Egnell is the founder of Ameda - a brand that millions of pumping parents use and recognize today. The SMB pump that he and Maja Kindberg built together became the foundation of a company whose mission has remained consistent for over eighty years.
The Mya portfolio of pumps was first introduced in 2019 as an ode to Sister Maja, a historic Ameda figure and co-creator of the modern breast pump. Sister Maja worked alongside Swedish inventor and Ameda founder Einar Egnell to develop the first breast pump that mimicked a baby's natural nursing rhythm and intensity.
Eight prototypes. One nurse. One engineer. A brand that still carries her name eighty years later.
Sources: Museum of Healthcare, The Egnell Breast Pump, MomMed, Breast Pump History, Yahoo Lifestyle, The History of Breastfeeding, USPTO, Ameda trademark filing.
We didn't guess at the fit. We tested it on real moms until it was right.
Egnell went through eight prototypes and asked lactating mothers what they actually needed. We designed Cushy the same way - iterating on shape and size with real pumping moms and IBCLC Jessica Anderson, until it flexed with the body instead of pinching it. Available in a wider size range than most hard-plastic flanges and compatible with most major pumps.
Shop Cushy FlangesWhat came next
The SMB pump was a hospital machine. It weighed forty pounds and it stayed on the ward. The question of when a pump would finally be designed to leave the hospital - to travel with a mother, to sit on a desk, to fit in a bag - was still decades away from being answered.
The pump that finally left the hospital
Next week we look at the pump that finally made the leap out of the maternity ward and into everyday life, and what it cost mothers to get their hands on one.
