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Mothers of premature infants may still be able to feed their babies breast milk if they can establish a good routine to express milk using a hospital-grade pump, a recent U.K. study suggests.

Pediatricians recommend that mothers exclusively breastfeed infants until at least 6 months of age because it can reduce babies' risk of ear and respiratory infections, sudden infant death syndrome, allergies, childhood obesity and diabetes.

But preemies often can't breastfeed because they're too tiny and lack the muscle strength and coordination to nurse, so they need pumped milk.

Even with the right equipment, making this happen takes a lot of time and hard work, particularly if women are recovering from cesarean deliveries or traveling a great distance to visit babies that remain hospitalized after their mothers are discharged, said lead study author Mary Fewtrell of the UCL Institute of Child Health in London.

"They will have to persevere with milk expression for a long time before the infant can be fully breast fed, and this requires a lot of effort," Fewtrell added by email.

Pregnancy typically lasts about 40 weeks, and infants born after 37 weeks are considered full term. In the weeks immediately after birth, premature infants often have difficulty breathing and digesting food. They can also encounter longer-term challenges such as impaired vision, hearing and cognitive skills as well as social and behavioral problems.

The study focused on some of the most vulnerable preemies: those born before 34 weeks gestation.

To see what factors might influence how easy it is for mothers to feed these preemies breast milk, Fewtrell and colleagues analyzed data on 62 mothers who participated in a study of different types of breast pumps.

As part of this experiment, the women completed 10-day diaries detailing the amount of milk they pumped as well as their opinions about the experience of pumping.

Women expressed more milk when they used what's known as a double pump that extracts milk from both breasts at once, rather than a single pump that only attaches to one breast at a time, the study found.

Over 10 days, half of the women using double pumps typically expressed about 109 grams (about 4 ounces) more per day than the mothers using single pumps, the study found.

More frequent pumping sessions also helped increase the total amount of breast milk the mothers could provide their babies.

Beyond its small size, another limitation of the study is its reliance on women to visually estimate the amount of milk they expressed when they pumped, the authors note in the Archives of Disease in Childhood - Fetal and Neonatal Edition.

Even so, the findings add to a growing body of evidence showing the benefits of double-pumping frequently to help establish a milk supply and produce enough to feed an infant, said JoAnne Flagg, a lactation specialist at Johns Hopkins University School of Nursing in Baltimore who wasn't involved in the study.

"No pump is as efficient as a baby as they use the suction of their mouth and mechanical extraction with their tongue," Flagg noted.

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But pumping both breasts increases levels of prolactin, a hormone involved in milk production, and increases mammary gland stimulation.

Supplementing with hand expression can also help increase the volume of milk produced, as can making sure the flanges on the pump - the parts that go against the breast - are the right size for the nipple, Flagg added.

SOURCE: http://bit.ly/23IggFF Archives of Disease in Childhood - Fetal and Neonatal Edition, online March 2, 2016.