How the PersonalFit PLUS & FLEX Medela Breast Shield Optimizes Pumping

Jenny Murray, BSN, RN / November 2020

Understanding Breastfeeding Benefits and Initiation Importance

Human milk is often referred to as “medicine” and, through research, we continue to expand upon benefits to a Mother’s Own Milk (MOM) diet.  Most recently, published research shows the robust antibody response to Sars-CoV-2 in human milk from mothers that have recovered from COVID-19.¹  MOM may be more important now than ever. 

While many recognize the immediate benefits of a MOM diet, it’s also important to be reminded about the lifelong benefits to both mom and baby:    

  • If an infant is born prematurely, MOM provides protection against necrotizing enterocolitis (NEC)², sepsis³, retinopathy of prematurity (ROP)⁴, bronchopulmonary dysplasia (BPD)⁵, as well as a host of other conditions that are associated with high morbidity and mortality rates.  
  • A term infant receives the benefit of immunity from mother as well as a decreased risk of diseases over a lifetime.  Breastfed infants are 13% less likely to become overweight or obese as children or teenagers, which lowers their risk of associated conditions, including type 2 diabetes, coronary heart disease and a number of cancers.⁶⁻⁸ 
  • Mothers benefit from providing breast milk as well.  For every 12 months a woman produces milk, her risk of breast cancer decreases by 4.3%, and this effect is cumulative.⁹

It goes without saying the easy part is talking about the benefits.  Breastfeeding and/or pumping is exhausting work for any mother and is done out of pure devotion and love for her most cherished gift – her baby.  It’s no surprise that when a mother does not meet her intended goals of breastfeeding, it takes a significant emotional toll.  It is so important to educate a mother and her support system on the benefits of an exclusive human milk diet so they can make an informed decision about their own personal breastfeeding goals.  These goals are different for all mothers.  Breastfeeding and/or pumping needs to be prioritized with a sense of urgency.  The first few hours, days and weeks are critical to ensure a mother is initiating appropriately and effectively to support long-term milk production. 

While we talk about the emotional toll it takes on a mom who does not meet her breastfeeding goals, let it not be because she “didn’t have enough milk” or because she “had pain with pumping.”  We have research-supported interventions to help a mom meet her lactation goals.

Use of a Medela Breast Shield Can Help

It is well-established through supportive research, including a randomized-controlled trial¹⁰, that the Symphony PLUS® hospital-grade (multi-user) pump is a key driver in assisting mom to initiate, establish and maintain her milk supply.  While the Symphony PLUS® breast pump has been researched and innovative changes have been made many times over the last 50 years, the breast shield has remained the same.  That posed the question, “could the shield be optimized?” 

Utilizing a unique database of 3D lactating breast scans to assess the fit of a shield, Dr. Danielle Prime, a lactation scientist at the University of Western Australia, and her team noted that in two-thirds of cases, the nipple did not reach inside the tunnel and the point of contact was at the outer edge of the rim, which could result in duct compression.  After researching different angles that better fit the contour of the breast, it was noted that indeed the shield could be optimized to yield a better fit.¹¹  The new shield design is known as PersonalFit™ PLUS (in hospital kits) and PersonalFit FLEX™ (in the retail market).

What is different?

The PersonalFit™ Legacy shield has a 90-degree angle and is round in shape.

The PersonalFit™ PLUS/FLEX shield has a 105-degree angle and is oval shaped.

What is different about the PersonalFit™ PLUS and PersonalFit FLEX™?

The only difference is the flexible outer rim on the PersonalFit FLEX™.  The hospital kit does not have the flexible outer rim because the molding cannot go through the sterilization process required by hospitals for sterile kits.  Both the PersonalFit™ PLUS and PersonalFit FLEX™ can be placed in the Quick Clean™ Micro-Steam™ bags for sanitization (as recommended by the CDC) every 24 hours¹². There is no research-based benefit to the flexible outer rim other than moms perceive it as more comfortable. 

How does the increased angle help?

The theory is that there is less duct compression.  With an improved fit, the nipple sits further into the tunnel and the point of contact is reduced at the outer rim.¹¹

What is the correct way to place the shield onto the breast?

There is not right or wrong way.  It can be placed however the mom feels most comfortable.  Research showed that two-thirds of moms rotated positions over the course of their pumping journey. 

It is important to note that the outer rim of the shield may not come in complete contact with the breast and that is okay.  Resist forcing the shield onto the breast or the breast into the shield.  This can cause duct compression, thereby decreasing breast drainage. 

How do I determine an appropriate breast shield size?

Sizing remains the same as in the past.  The improved fit (contour better fits the shape of the breast) makes sizing more critical now than ever.  Sizing guidelines have not changed, though.  You can find an easy sizing guide here under “Tools for Families.”

What did the research show that prompted the new breast shield design?

  • More Milk
    • After 15 minutes of pumping, 11.8% more milk was obtained¹³
    • 4% improvement in breast drainage.¹³  Draining the breast well is key to maintaining milk production.¹⁴
  • More Comfort
    • Mothers described pumping as more gentle and natural¹⁵

Together with the Symphony PLUS® pump technology, the new PersonalFit™ PLUS/FLEX shields work to optimize expression when we know it is needed most!  Despite the pandemic, we know, through research, that human milk continues to be the cornerstone to lifelong health benefits. 

To learn more about PLUS, visit

Get in touch with our team to learn more about PersonalFit PLUS Breast Shields for your practice.


  1. Fox A, Marino J, et al. Evidence of a significant secretory-IgA-dominant SARS-CoV-2 immune response in human milk following recovery from COVID-19 medRxiv 2020.05.04.20089995; doi:
  2. Sisk PM, et al. Early human milk feeding is associated with a lower risk of necrotizing enterocolitis in very low birth weight infants. J Perinatol. 2007 Jul;27(7):428-33.
  3. Patel AL, et al. Impact of early human milk on sepsis and health-care costs in very low birth weight infants. J Perinatol. 2013 Jul;33(7):514-9.  
  4. Romaine A, et al. Predictors of Prolonged Breast Milk Provision to Very Low Birth Weight Infants. J Pediatr. 2018;202:23-30.e1. doi:10.1016/j.jpeds.2018.07.001
  5. Patel AL, Johnson TJ, Robin B, et al. Influence of own mother's milk on bronchopulmonary dysplasia and costs. Archives of Disease in Childhood - Fetal and Neonatal Edition. 2017;102:F256-F261.
  6. Horta BL, et al. Long-term consequences of breastfeeding on cholesterol, obesity, systolic blood pressure and type 2 diabetes: a systematic review and meta-analysis. Acta Paediatr. 2015 Dec;104(467):30-7. doi: 10.1111/apa.13133.
  7. Kwan ML, et al. Breastfeeding and the risk of childhood leukemia: a meta-analysis. Public Health Rep. 2004;119(6):521-535. doi:10.1016/j.phr.2004.09.002
  8. Amitay EL, Keinan-Boker L. Breastfeeding and Childhood Leukemia Incidence: A Meta-analysis and Systematic Review. JAMA Pediatr. 2015;169(6):e151025. doi:10.1001/jamapediatrics.2015.1025
  9. Breast cancer and breastfeeding: collaborative reanalysis of individual data from 47 epidemiological studies in 30 countries, including 50302 women with breast cancer and 96973 women without the disease. Lancet (London, England). (2002);360(9328): 187–195.
  10. Meier PP, et al. Breast pump suction patterns that mimic the human infant during breastfeeding: greater milk output in less time spent pumping for breast pump-dependent mothers with premature infants. J Perinatol. 2012;32(2):103-110.
  11. Muther M, Prime DK, et al. Scans of the lactating breast can be used to investigate the breast:breastshield interface (P‐24); Abstracts from the 18th International Society for Research in Human Milk and Lactation Conference. Breastfeed Med. 2016; 11: A28.
  12. How to Keep Your Breast Pump Kit Clean: The Essentials. (2020, July 8). Retrieved from:
  13. Prime DK et al. 6th ABM Europe Conference, Rotterdam, NL; 2018
  14. Kent JC, Prime DK, Garbin CP. Principles for maintaining or increasing breast milk production. J Obstet Gynecol Neonatal Nurs. 2012 Jan-Feb;41(1):114-121. doi: 10.1111/j.1552-6909.2011.01313.x.
  15. Clinical study. (NCT02492139). 2016.

About the Author

Jenny Murray, BSN, RN, began her career 18 years ago as a neonatal nurse in neonatal intensive care. She has since served in a variety of nursing leadership roles within the NICU. Her experience in those roles has driven her love for education and research, especially educating and supporting clinicians in the advancing, innovative world of neonatology. Jenny currently works as a Clinical NICU Specialist for Medela LLC.

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