Eight-year operation status and data analysis of the first human milk bank in East China

Data from August 2013 to July 2021 were extracted from the computerized information management system of our HMB. The extracted donor data included age, education, residence address, occupation, number of children, number of donations, etc. Additionally, the results of bacteriological tests done before and after pasteurization were obtained. The extracted recipient data included gestational age, birth weight, mode of childbirth, number of days that DHM was used, etc.

Prior to January 2016, donors who passed the health screening, serological test(including hepatitis B virus(HBV),hepatitis C virus(HCV), Human Immunodeficiency Virus(HIV), syphilis and cytomegalovirus(CMV)), and their DHM passed the bacteriological tests (including bacterial species and count of bacterial colonies,both pre- and post-pasteurization) at the time of the first donation were considered to be qualified and allowed to donate in the future. Then their DHM was used without pre- or post-pasteurization bacteriological tests. After the continuous quality improvements [11] starting in January 2016, donors are also eligible if they pass the health screening, serological test, and and their DHM passed the bacteriological tests(both pre- and post-pasteurization tests) at the time of the first donation. But these qualified donors’ DHM at the same day was first pooled and then pasteurized. In the early stage of quality improvement, bacteriological test was conducted before and after the pasteurization of each batch every day. It was subsequently found that our milk extraction process and pasteurization process were reliable if the batches passed most of the tests, and thereafter, bacteriological test was conducted every 10 days. These batches was discarded before pasteurization if failing the pre-pasteurization bacteriological test, and also discarded after pasteurization if failing the post-pasteurization bacteriological test.

All eligible donors receive on-site guidance by professionals and their essential information was recorded at the time of their first donation. Before breast milk collection, the donors are requested to wash their hands under strict instructions and clean their breasts with antiseptic wipes, especially around the nipple and areola. An electric milk pump is used, and all accessories are cleaned and disinfected before and after use. The collected breast milk is placed in a dedicated storage container and placed in a 4℃ refrigerator, and all the relevant information is recorded. All the donor milk is mixed and pasteurized (by continuous disinfection at 62.5 °C for 30 min) within 24 h after collection and then stored in a special -20℃ refrigerator for no more than 3 months. When the DHM was used, the information about recipient, duration and volume of usage is recorded (Fig. 1).

Our HMB was approved by the ethics committee of Maternity Hospital Affiliated to Nanjing Medical University before it was established. Potential donors are provided with the necessary information and sign the consent form before their first donation. Additionally, a medical informed consent form is signed by the parents of the recipients before DHM is provided. All the donors are anonymous and babies receive DHM from multiple donors.

Our HMB is equipped with an independent milk collection room, a hospital-level milk pump, a pasteurizer (temperature-controlled water bath), human milk storage containers, medical refrigerators (including a custom-made ordinary refrigerator and special ultra-low temperature refrigerator), computers with a supporting information management system, etc. The guidelines for organizational management; infrastructure; donor screening; and the collection, processing, storage, and provision of donated breast milk are in accordance with The Human Milk Banking Association of North America.

The total cost for 8 years was ¥1.94 million($306,051) for 7,396.5L of qualified DHM, mainly on testing and consumables. Both donation and provision of DHM are free. The average cost per liter of DHM was ¥262.3($41.4). Before the establishment of the HMB, we received a donation of ¥1 million from a group of good Samaritans, whom were parents of patients or private donations, as start-up capital. The rest of the expenses were borne by our neonate department, which covered 80% of the cost, and the hospital, which covered 20% of the cost. The annual cost with its breakdown is shown in Table 1.

Between 1 August, 2013, and 31 July, 2021, a total of 1,805 mothers were enrolled, but 250(13.9%) did not pass the health screening or serological tests or their DHM did not pass the bacteriological test. The remaining 1,555(86.1%)qualified donors were mostly between 25 and 30 years of age (55.5%): 62.6% had a bachelor’s degree, 61.2% had given birth by vaginal delivery, 66.7% had had term births, and 80.1% were primipara (Table 2). Further, 46.2% of donors had donated milk more than 10 times (Table 2).

The total number of donation times in 8 years was 19,089, and the annual maximum number of donation time for individual donor was 195 (Fig. 2A). In 2013, the number of qualified donors was 91 and the volume of qualified DHM was 102.2 L. As a result of continuous quality improvements, January 2016 [11] witnessed a significant increase in both the volume of qualified DHM(1519.3L) and the number of qualified donors(304). In 2020, the number of patients at our NICU decreased due to the COVID-19 pandemic, and the volume of qualified DHM(537.9L) and the number of qualified donors(46) consequentially decreased (Fig. 2B and C).

Prior to January 2016, both pre- and post-pasteurization bacteriological test was conducted on qualified donors’ DHM only at the first time of donation. The data of these part was not recorded. From January 2016, on average, 95.4% of the batches passed the pre-pasteurization tests, and 96.3% passed the post-pasteurization tests (Fig. 3).

Over the 8-year study period, a total of 5,775.2 L of DHM was supplied to 9,207 infants (Fig. 2C), and the maximum individual volume was 13.7 L. Most of the recipients were preterm (83.3%), and 81.7% were single birth. In 64.4% of the recipients, the birth weight was between 1,500 g and 2,500 g, and in 41.7%, gestational age was between 34 to 37 wk. Further, 94.3% of them received DHM for less than 15 days, and the average of duration for receiving DHM was 4.5 days (Table 3).

This study describes the operations of our HMB and analyzes the data gathered over the last 8 years of its existence. Over the 8-year period, the total expenditure of the HMB was 1.94 million RMB($306,051), including employee salary, materials costs, test costs, etc., and both the donation and provision of DHM were free. The average cost per liter of qualified DHM was ¥262($41.4). In comparison, studies from the United States have calculated that 1 L of DHM costs approximately US $150, and studies from Germany have reported a cost of $94 per liter of DHM [12‐14]. The costs of our HMB are probably lower because most donors are not required to repeat the HBV,HCV,HIV and syphilis test when they donate within 6 months of their serological test, which is done during hospitalization at the time of delivery at our hospital. The cost of providing DHM is much higher than the cost of formula and mother’s own milk. However,breastfeeding could reduce the incidence of diseases, such as necrotizing enterocolitis and late onset sepsis, and save a lot of future medical costs [15]. Therefore, we also advocate and promote breastfeeding through various means, such as propaganda and education of breastfeeding to parents and medical staffs, etc., at our HMB.

Over the 8-year period, a total of 250 mothers(13.9%) did not meet the criteria for donation because they did not pass the health screening or serological test or their DHM did passed the bacteriological tests (Table 1). In 2015, a total of 169 mothers did not qualify because the CMV-DNA test of their DHM was positive, and this phenomenon exists in most Chinese mothers [16]. In fact, after pasteurization or freeze, the CMV-DNA test shows negative results, which means that the donor milk is not likely to cause neonatal infection [17]. Thus, after the continuous quality improvements that were initiated in January 2016, we only used the donors’ serum CMV test(including IgG and IgM) for screening.

During the last 8 years of operation of the HMB, the number of qualified donors and the volume of qualified DHM first showed an increase and then a decrease. In 2016, we carried out quality improvement programs for the HMB, including conducting propaganda and education of breast milk feeding, establishing education sites of breast milk donation, maternal and child health publicity in shopping mall, improving the process of breast milk donation and processing, ect. [11]. These programs resulted in a considerable increase of the number of qualified donors(304) and the volume of qualified DHM(1519.3L).In the first three months of 2020, due to the restrictions policy for donors coming to the hospital, our HMB did not receive any DHM no matter collected at home or at our HMB.Then the epidemic eased and our HMB gradually returned to normal work. Therefor, the number of qualified donors(46) and the volume of qualified DHM(537.9L) decreased significantly in 2020.

Our donors were mainly aged between 25 and 30 years, and this is similar to the donor demographic of HMBs reported in Taiwan and Thailand [18, 19]. 33.3% of the donors in the present study delivered preterm infants. It is mainly because the mothers of preterm infants have a reduction in postpartum lactation due to physical reasons [20] and they did not have added breastmilk for donation. In the present study, 61.2% of donors gave birth by vaginal delivery. This percentage is different from that reported in Thailand [17], but is similar to a previous report in mainland China [7]. Further, 46.2% of the donors in this study donated more than 10 times, which is higher than the percentage reported in mainland China and indicates that we have a higher average number of donations than other domestic HMBs. This is probably attributable to the efforts of our staff in providing correct information and following up with donors. Additionally, 62.6% of the donors had a bachelor’s degree, which meant well-educated mothers tend to have better knowledge about and attitude towards milk donation [21]. Most of the donors began to donate milk at 1 month postpartum at the earliest, and the number of donors who started to donate deceased rapidly at 3–6 months postpartum. The main reason is probably that most women in China are only given 4–6 months of maternity leave. Once they resume work, their free time and volume of lactation probably decrease dramatically.

Although holder pasteurization (HoP,62.5°C for 30 min) may reduce the immunological components in donor milk, such as sCD14, however, this has little impact on the protein, fat, carbohydrates, some trace elements, and the activity of some enzymes [5, 22] that are very important and irreplaceable for the development of neonates, especially premature infants. Recently, a high-temperature short-time treatment(HTST, 72°C for 30s) was designed as an alternative for HMBs, which resulted in better preservation of the nutritional quality of DHM than HoP because relevant thermosensitive components (phospholipids, PUFAs, and BSSL) were less affected [23]. But we still choose HoP instead of HTST because the duration of HTST treatment, which had a greater influence on the nutrient composition of DHM than did the tested temperature, was harder to control [23].

The DHM in our HMB was only supplied to the neonates in our NICU and was not continued after discharge, and it was provided free of cost. This model is different from that described in previous reports from Thailand and the UK,which provide DHM for non-hospitalized infants [24, 25]. During the 8-year period, 9,207 newborns received DHM, most of whom were premature infants (80.1%), and the newborns had severe infection, feeding intolerance, and necrotizing enterocolitis. The maximum volume per neonate was 13.7 L, which was used by an extremely premature infant. The duration of use of DHM was mostly less than 15 days, and the average duration was 4.5 days, which is shorter than that previously reported in Scotland [26]. This is probably because most mothers have expressed enough breast milk to feed their own babies after a certain time point.

During the COVID-19 pandemic, China implemented strict restriction policy, so we also added COVID-19 nucleic acid testing to the donor screening tests. Visitation was forbidden during newborn hospitalization, and patients from other provinces were not admitted to come to our hospital until recently. From February 4^th to March 4^th 2020, breast milk donation and transport to the hospital were not allowed in our hospital. These policies led to a significant reduction in both the number of donors and volume of DHM. Although this was accompanied by a significant reduction in the number of newborns as well as the demand for DHM in our hospital, due to pregnant women in other cities could not come to our hospital for childbirth, these conditions also led to the depletion of DHM stored at our HMB. However, it is worth noting that there was no case of COVID-19 infection at our hospital during this period.

HMBs could support and promote breastfeeding, and provide better choices and better nutritional treatment options for children who cannot be breastfed by their mothers, especially premature infants. Additionally, it is very important in raising social awareness about the benefits of breastfeeding or DHM feeding, and actively publicize and provide breastfeeding guidance. Over the 8 years of operation of our HMB, through continuous quality improvement, our processes have been gradually finetuned and made efficient, and we will continue to provide DHM to newborns in the future, and provide some recommendations to other HMBs operating in China.