Does Warming the Breasts Affect the Amount of Breastmilk Production?

Abstract

Background and Objective:

Increasing the amount of breastmilk is vital for both the nursing mother and child. Warming up breasts before using electrical pumps to pump out breastmilk may help to increase the amount of breastmilk, especially in the mothers of babies who are being nursed in the neonatal intensive care unit.

Subjects and Methods:

Thirty-nine mothers whose babies had been admitted to the neonatal intensive care unit were analyzed. A breast compress that was warmed up in a microwave oven for 1 minute at 180 W was applied to one of the breasts for 20 minutes, and both breasts were sucked by an electrical breast pump for 15 minutes. The amount of breastmilk after each procedure was recorded.

Results:

The amount of breastmilk that was obtained from warmed breasts was significantly higher than that obtained from nonwarmed breasts (maximum, 47.02±23.01 mL vs. 33.15±19.98 mL) (p=0.000).

Conclusion:

Warming up breasts by a breast compress is easy and affordable, and this procedure increases the amount of breastmilk, thus facilitating infant nutrition and recovery especially in the neonatal intensive care unit.

Background and Objectives

Human milk is a unique nutrient designed for the needs of the baby, especially in the first 6 months of life, and is fully compatible with the gastrointestinal system of the baby. Therapeutic warming of tissues is known to increase the local blood flow, local metabolism, and excretion of local waste products and to facilitate tissue nutrition and renewal and phagocytosis.¹ Warming the breasts also facilitates the action of the oxytocin reflex. Newton and Newton² showed long ago that application of cold to breasts inhibits the let-down reflex, whereas heat application could facilitate this reflex. Cold therapy is also useful in the management of breast engorgement due to overproduction of milk.³ Our aim was to investigate the effect of warming of breasts of mothers whose babies were being nursed in the neonatal intensive care unit (NICU), who were unable to directly breastfeed their babies and who were using an electrical breast pump.

Subjects and Methods

The study was carried out at the NICU of Zeynep Kamil Maternity and Children's Training and Research Hospital, Istanbul, Turkey. Forty mothers whose babies were being treated at the NICU and who were using an electrical breast pump to obtain their breastmilk were included. One of the mothers had to leave the study before completion, so the study was completed with 39 mothers. The following criteria were used for inclusion in the study: No history of breast operation, the baby was unable to suck, and the baby was less than 21 days old.

When the mother was included in the study, one of her breasts were randomized to the warming or control group by using a computerized randomization program. In this way, the right breasts of some women and the left breasts of others were warmed. This study was not blinded. In the study group, a breast compress made from gel (mainly a hot pack manufactured in the form of a single bra cup) that was warmed up in the microwave oven for 1 minute at 180 W was applied to the breast for 20 minutes. The temperature of the breast compress was measured before applying it to the mother. The maximum temperature of the compress was 40.5°C, which was quite tolerable for the mothers. If it was more than 40.5°C, the breast compress was discarded, and another pad was heated. Afterwards, both breasts were pumped by an electrical breast pump for 15 minutes simultaneously. The amount of breastmilk obtained from the breasts was recorded. This procedure was repeated twice a day at the same daily interval for 3 days.

Informed consent was obtained from all mothers before recruitment. The study was approved by the Institutional Board.

Results were analyzed with SPSS version 12.0 software for mean, median, and t test at the 95% confidence interval and a significance of 0.05.

Results

A warm breast compress was applied to 20 left and 19 right breasts. The mean age of the mothers was 30.8±5.4 years. Regarding education, 53.8% had graduated from primary school, whereas 30.8% were high school and 19.3% were university graduates; two mothers (5.1%) were illiterate. Of the babies, 64.1% were born by cesarean section, and 66.7% of them were boys. Their mean birth weight was 1,984.87±749.16 g. The main reason for their admission to the NICU was prematurity (79.5%). Of the mothers, 76.9% had antenatal follow-up. During the study period, the breasts were pumped twice a day for 3 days (i.e., six times). In all six times, the amount of breastmilk obtained from the breasts that were warmed up was significantly higher than that obtained from nonwarmed breasts (p=0.000) (Table 1).

Table 1.

Mean Amounts of Breastmilk in Warmed and Nonwarmed Breasts

	Amount of breastmilk (mean±SD) (mL)
Attempt	Warmed breasts (n=39)	Nonwarmed breasts (n=39)	t	p
1 (Day 1)	30.28±25.04	20.64±20.42	6.60	0.000
2 (Day 1)	28.07±20.76	16.89±15.75	7.44	0.000
3 (Day 2)	44.10±32.56	33.00±28.59	7.65	0.000
4 (Day 2)	39.69±25.45	27.30±20.20	8.02	0.000
5 (Day 3)	47.02±23.01	33.15±19.98	8.06	0.000
6 (Day 3)	45.07±21.75	32.05±19.68	8.85	0.000

Discussion

Our results show that warming up breasts before using an electrical breast pump is associated with a significant increase in the amount of breastmilk. The reason is unclear, but it may be through the dilation of milk channels and preventing the obstruction of these channels, rather than improving the amount of breastmilk produced. Warming may also stimulate the oxytocin reflex. Our literature search did not reveal any similar studies. Ramsay et al.⁴ have showed ultrasonographically that under normal circumstances, the amount of breastmilk is equal from both breasts. This implies that the significant difference we have observed in our study is due to the increase in the amount of extracted breastmilk by warming up the breast. With the use of high-resolution ultrasonography, the diameter of the ducts in the breasts and the flow rate of human milk in these ducts may be determined, and the amount of ejected milk may be calculated.⁵ However, this is a stressful method for the lactating woman, and by using electric breast pumps, the flow rates of milk may be determined without using ultrasonography in order to identify the amount of milk ejection.⁶ Because we did not have the appropriate equipment, we were unable to use high-resolution ultrasonography and determine the flow rates of milk ejection. Nonetheless, we measured the amount of expressed milk from the breasts, which showed the beneficial effect of breast warming. A similar study by using ultrasonography and electrical breast pumps may also be contemplated.

Premature babies and others who are in the NICU are in need of breastmilk perhaps more than other babies because breastmilk has many properties that are important for sick babies. Therefore, increasing the amount of breastmilk and nursing the babies with more breastmilk as long as they are able to receive it will facilitate their recovery and early discharge from the hospital. Early recovery and early discharge have innumerable benefits, medically, ethically, and financially.

Conclusion

Warming up breasts is associated with a significant increase in the amount of breastmilk.

Footnotes

Disclosure Statement

No competing financial interests exist.

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