Breast Milk Production - how to increase?

Mix of Hand Techniques, Electric Pumping May Increase Milk Production in Mothers of Preterm Infants
Deborah Brauser
From Medscape Medical News

July 23, 2009 — Mothers of preterm infants can avoid insufficient breast milk production by combining hand techniques with electric pumping, according to results of an observational study reported online July 2 in the Journal of Perinatology.

"Many immediate and long-term benefits of breastfeeding for the preterm infant and mother depend on exclusivity and duration, with the strongest determinant of both being milk production," write Jane Morton, MD, from the Department of Pediatrics at Stanford University School of Medicine, California, and colleagues. "Insufficient production in the first 6 weeks postpartum is the most common reason for discontinuing lactation, 2.8 times more frequent in mothers of preterm than those of term infants."

The authors write that if nutrition from breast-feeding is inadequate for the preterm infant, mothers must "triple feed" — meaning breast-feed, bottle-feed, and pump — to maintain production, a regimen likely to cause the high breast-feeding attrition rates seen in mothers with low production.

In addition, the study authors add that volumes lower than 500 mL/day by postpartum week 6 predict early weaning, whereas higher volumes facilitate the transition from bottle (or tube) feeding to breast-feeding by reducing the effort required for milk transfer. "Thus, maximizing milk production is essential for prolonged breastfeeding."

Past efforts to improve production have primarily focused on pumping schedules and pump design, such as electric vs manual. However, few studies have looked at the use of manual techniques to increase milk yield.

Pump Suction Alone Often Not Enough

"We have observed that pump suction alone often fails to remove a significant fraction of milk as more can be expressed using manual techniques," write the authors. They explain that it may be more effective to use hand expression to remove colostrum before mature milk "comes in," followed by hands-on-pumping (HOP) — a combination of pump suction, breast compression, and hand expression — once volume increases.

The investigators' objective "was to use a prospective observational cohort study to determine whether the use of 2 manual techniques, hand expression of colostrum and HOP of mature milk, could promote establishment and sustainability of a sufficient milk supply." They also examined variables that may affect lactation.

From 2004 to 2006, a convenience sample of eligible mothers of preterm infants (those weighing <1500 g, <31 weeks' gestation) were invited to participate in this observational study. A total of 67 patients were enrolled and instructed on pumping, hand expression of colostrum, and HOP. All were given a Symphony pump (Medela Inc) for the duration of the study or the hospitalization of the infant, whichever was longer.

The investigators collected maternal perinatal information and histories through chart review, questionnaires, and interviews. The mothers recorded their own milk expression information, including date, time, duration, and volume removed from each breast for 8 weeks. Predetermined and modifiable variables were examined at both 2 and 8 weeks postpartum, with only those patients who completed 6 or more days of records for both weeks included in this study.

Hand Expression and Electrical Pumping

The participants were told to begin using the electric pump within the first 6 hours postpartum. Before the onset of copious milk production, they were instructed to "double pump" (pump both breasts simultaneously) 8 times per day for 15 minutes and to hand express colostrums as frequently as possible in the first 3 postpartum days. Once mature milk "came in," they were advised to pump 8 or more times per day until they could express only drops.

After being discharged, mothers were invited to return to the hospital for monitored, instructional HOP sessions. During this time, milk was collected via 2 tubes connecting the breast shields to bottles placed on 2 electric scales, which were linked to a computer that recorded milk removal during the expression period. Each session began by double pumping with the electric pump while simultaneously compressing the breasts and massaging firmer areas.

Once milk flow stopped, double pumping was stopped, breasts were massaged briefly, and the mothers then attempted removal of remaining available milk using whatever technique they chose: double pumping, single pumping, or hand expression only.

Of the 67 enrolled mothers, 52 (78%) stayed in the study for the entire 8 weeks, with 48 completing 6 or more days of records for both weeks 2 and 8. The mothers with complete records were significantly older (P < .001), had more formal education (P < .02), and were more likely to have undergone in vitro fertilization (P < .03).

Results showed that mean daily volumes rose to 820 mL/day by week 8 for all participants (with 75% having >500 mL) and 955 mL/day in mothers who hand expressed more than 5 times per day during the first 3 days.

HOP Increased Milk Production

To determine whether pump-dependent mothers could achieve sustained sufficient milk production using HOP during the 8-week study, mean daily volumes during the 3 days before HOP instruction were compared with week 8 mean daily volumes for each mother with complete pre- and postrecords. A total of 92.9% of the mothers taught HOP had increased milk production; and mean daily volumes of milk increased by 48% (from 583 ± 383 mL/day to 863 ± 506 mL/day; P < .003).

Predetermined variables related to week 2 and/or week 8 mean daily volumes were maternal age and gestational age, with modifiable variables being pumping frequency, duration, and longest interval between pumping.

The authors write that the most intriguing study findings were "the unfaltering and impressive breastmilk volume of preterm infant mothers, who are considered to be at high risk for impaired milk production;...the finding that 2 practices not routinely prescribed, hand expression of colostrum and HOP expression of mature milk, may influence volume; and finally, the lack of correlation between volume and variables believed to influence production in breastfeeding mothers (type of delivery, maternal [body mass index], history of previous breastfeeding, multiples, [in vitro fertilization]) suggests that these factors may be mitigated by techniques supporting effective and frequent milk removal."

Limitations of this study included the expertise of the investigators in HOP instruction, the lack of a control group, and a single hospital-based population with a high level of education and lack of ethnic diversity.

"Ours is the first report of a steady increase in [milk] production over 8 weeks, which surpasses reference levels for mothers of term infants," conclude the study authors. They add that a larger, prospective, randomized, controlled trial is needed to validate the observed benefits.

J Perinatol. Published online July 2, 2009.