Step 1. Determinants of breastfeeding and expectation on the appOnline survey on app features and contents

The majority of 49 respondents (7 fathers and 42 mothers) were from Hanoi (74%), where the study was conducted. They all had children under 5 years old.

Time to install the app

81% wanted to install the app during pregnancy, and 17% wanted to have it after delivery.

Desired app functions

Respondents preferred the app which helped to monitor child development, send notifications, and remind of upcoming events, had information on maternal and child care, and the ability to search for needed information. Posting questions, sharing information, discussing, or receiving notifications on those posts were less preferred. Some other functions were suggested such as liking the app with clinics/hospitals for pregnant care or child care or searching nearby pediatrics hospitals, receiving counseling from experts, music for mothers and newborns, etc.

Frequencies of receiving push notifications

Equal proportions (33%) of participants wanted to receive push notifications daily or 2–3 times per week and only less than a quarter of participants would prefer to receive push notifications once a week (22%).

Content of push notifications

Each notification should contain a piece of information, the more information the better (63%). Receiving repeated messages every 4 weeks was selected by nearly one-third of the participants (33%).

After discussion within the research group, we decided to design and install the app for mothers during a pregnancy instead of after delivery as originally planned. Push notifications were auto-generated three times per week during pregnancy and two times per week after delivery. Notifications were repeated every 4 weeks to make sure all mothers received the messages before delivery.

Information preferences

The preferred information was divided into three groups: maternal care, child care, and breastfeeding. For maternal care, participants were keen to receive information on mental health, birth preparation, nutrition, and living with their parents-in-law rather than monitor the gestational weight gain during pregnancy or have sex during pregnancy. For child care, participants liked the information on the management of child health during illness, immunization, and monitoring an infant’s progress rather than on feedings. During breastfeeding, mothers asked about nutrition for mothers, issues related to breastfeeding, and difficulties rather than expressing and storing breast milk or infant formula.

Qualitative research findings

Among 22 participants, three mothers were pregnant with their second child, 5 had a child aged under 6 months, 5 had a child aged 6–12 months, and 9 had a child over 12 months. About 7 of 22 mothers had exclusively breastfed, 12 had both breastfeeding with additional formula feeding and three had used infant formula only. Ten mothers had a vaginal delivery and the remainder had a cesarean delivery.

From mothers

Early initiation of breastfeeding was the most difficult for mothers, particularly among those who had a cesarean delivery. Someone else (grandparents, fathers, health care workers) took care of their newborn while mothers often found the milk did not “come in” in the first days.

“I had a cesarean section. There was no skin-to-skin contact. The doctors took the baby out of the operating room and bring to her grandmother. After the operation, I was alone in a postnatal room for the whole day. On the second day, I was in pain and could not move, I did not have any drops of milk, and I could not sit up. So, grandmothers took care of her and gave her only bottles”. (0304Text2).

When milk had “come in”, mothers had a lack of knowledge and experience in dealing with difficulties during breastfeeding and often turned to an easier option of formula feeding with support from family members.

“On day 10th, I had a fever, I didn’t know it was mastitis at that time. I could not express milk much. It was so painful. I clicked my tongue: “let’s feed her with formula, I don’t have much milk, she is hungry and crying. Pumping causes soreness in nipples, tiredness, shivering, and fever but not much milk is extracted”. So, I did not eat much, and ran out of milk after 20 days. I fed my baby with formula completely since then”. (0904Text4).

Some examples of difficulties during breastfeeding were their infant not focusing on breastfeeding, both playing and sucking at the same time, prolonged time taken for breastfeeding compared with bottle feeding; a child sleeping while breastfeeding, which did not happen with bottle feeds; a child ‘demanding’ feeds too often and the mother didn’t get enough sleep at night and breastfeed refusal. Mothers were also stressed and blamed themselves as “bad mom” when breastmilk was not yet ejected or not enough, newborns gained no weight, etc. Good preparation and planning for breastfeeding during pregnancy would help to adapt to breastfeeding.

“On the third day, there was still no milk as full as I thought. I began to panic and was afraid of not having enough breast milk. I remember when I attended an antenatal class, the counselor repeated again and again that “if you think you don’t have enough milk for the baby, you won’t have enough milk for real! You must be relaxed and comfortable!”. I called my sister for support and reassurance. I tried to reassure myself and not to feed with formula. In the evening of the third day after giving birth, the milk came in a lot”. (0904Text3).

From family members

The husband could help his wife in preparing food, cooking, and clean for the baby. However, most of them did not have a preference for either breastfeeding or infant formula and seemed to follow the mother’s or grandparent’s decision. Messages which focused on, or emphasized the love between the father–newborn and husband-wife would involve the husband in helping with breastfeeding.

“My husband said nothing, but he seemed to follow grandparents who supported stopping breastfeeding. He thought I would be tired from being woken -up many times to breastfeed the baby at night”. (0904Text1).

The mother-in-law is the most influential person. She was very helpful in caring for newborns and mothers as local birthing traditions did not support new moms doing housework in their first month after delivery. However, the differences in lifestyles and caring could create more stress for first-time mothers.

“After giving birth, I was very tired. My son was the first grandchild of a big family. His grandmother hugged and carried him almost all day. I was even not allowed to hold him. I could not have skin-to-skin contact for the first 12 hours as I wanted. When he cried, I told the grandmother to let me breastfeed him, however, she scolded me: “He′s hungry! How can you feed him when you have no milk!” (0904Text3).

Grandmothers often turned to use infant formula to enable them to feed a child whenever he/she cries, a preference for a “chubby” baby. They had also been exposed to infant formula advertisements on television. Involving family members in the preparation and planning for breastfeeding during pregnancy would support their breastfeeding decision and practice.

Step2. The design, function, and content of the app

We used results from the literature review and the formative research above to identify and design the app functions.

2a. App function and design

Being simple and easy to use and the ability to function without internet access were important criteria for the app functions.

The app function included (a) push notifications: a short message service (SMS) system to continue delivering information to mothers about target behaviors and encourage them to use the app; (b) library information which contains threads explaining the short messages. Two versions of the app were available, one for the intervention and the other for the control app. In the intervention version, the mother received messages and library information on breastfeeding and maternal and child health care. In the control one, no information on breastfeeding was given, the mother received messages and library contents on maternal and child health care only. In the trial, the researchers randomized the mothers into either of the version based on age, educational level, and parity [20].

The app Bebo allowed mothers to (1) Register; (2) Receive messages at a desired day and time in a week; (3) Reread the messages; (5) Touch the messages to open the related thread in the library content; (6) Read and search information in the library content. During the trial, the app needed to register with a password provided by the researcher for a randomized controlled trial study. This password was removed after the project ended.

Interface design

This theme refers to the design and layout, including consistency, location of icons, functions on each screen, font, color, density, placement, and images [26]. The graphic design was developed to be clear and intuitive to highlight the messages on breastfeeding. The logo of the Bebo app described a mother holding her baby and all were protected by a drop of breastmilk. Green was symbolic of nature and healthy growing up. Ochre could capture attention quickly, and evoke certain moods, it represented the stability of our environment and even influenced behavior and well-being (Fig. 2). A screenshot of log-in showed simple functions of library content, notifications, and search (Fig. 2).

Fig. 2

Home screen and notifications log

Push notifications

The notifications conveyed messages on targeted behaviors. Users could tap the messages to open the related thread in the library information. Messages were designed to be re-readable at any time in the app [23], automatically generated, and sent to mothers’ phones without internet access three times per week during pregnancy and two times per week after delivery.

During pregnancy, the notifications were re-sent after every 4 weeks to make sure participants received a full set of 12 messages before delivery. After delivery, the messages were released according to key development milestones of the baby Users could tap messages on the home screen to access expanded content in the libraries.

Messages could be reread at any time in the app. They were about tetanus vaccination, weight control during pregnancy, maternal nutrition, folic acid supplementation, other micronutrient supplementation, physical activities, and smoking.

Library information

Each message was linked with one piece of information in the library (a thread). They were repeated every 4 weeks but the information in threads was different to provide more information and keep the mother reading. Each thread contained the message, the title of the thread related to the messages, a picture to illustrate messages or information in the thread, references, and links for further reading. The thread could be opened and read at any time without internet access. The library content for the control group also appeared in the intervention version. Library content for the intervention group did not appear in the control version (Fig. 3).

Fig. 3

Library content of the intervention (left side) and control (right side) group

The design of the triple–blinded controlled trial

The design of the triple–blinded controlled trial is shown in Fig. 4.

(1)

The data collector interviewed mothers using Research Electronic Data Capture (REDCap) and each mother was given a unique identifying number.

(2)

Registration

2.1

The data collector team downloaded and installed the app and then launched the app for the first time to subscribe to push notifications with firebase cloud messaging or apple push notification service.

2.2

The app registered the device to firebase cloud messaging or the apple push notification service.

2.3

The firebase cloud messaging or apple push notification service accepted the app and sent it to the app as a device token.

2.4

The data collection team updated the mother’s profile including the mother’s name, identifying number, phone number, and the desired date of the week’s notifications.

2.5

The app sent the mother’s profile including the device token to the Webapp (the app was now waiting for activation of the version).

(3)

Randomization

3.1

The administrator used information from REDCap (mother age, educational level, and parity) for randomizing the mother into either the control or intervention group. He then updated the mother’s group in their profile on Webapp to assign them either a control or intervention version.

3.2

The administrator sent an alert to the mother to open the app for activation.

3.3

The Webapp sent the notification to the mother app via firebase cloud messaging or apple push notification service based on the device token.

3.4

The firebase cloud messaging or apple push notification service sent the notification to the mother app based on the device token.

(4)

Activation

4.1

Mother touched or opened the notification to activate the app without notice of the app’s version.

4.2

The app requested the mother’s group from Webapp to create the scheduled local notifications and finished the app registration and activation.

Fig. 4

Only the administrator could extract information from REDCap and Webapp. In the follow-up phone call, the admin provided data collectors with name, identity number, phone number, and expected birthdate which were extracted from the Webapp. Data analysts would be provided with a data set without information on the control/intervention group.

2b. Design content of the app Messages or push notifications

We first identified target behaviors, then key determinants, and applied BSE theories for developing the messages and library content (Table 1). Barriers and facilitators to breastfeeding were identified from the review and the qualitative research above. The messages were targeted at not only mothers but also included fathers, mothers-in-law, or families [27].

Table 1 Example of the framework for developing messages Library information

Findings from the literature review and formative research were used as a guide to identify the content needed in the library. For example, we included information on managing a crying child [28, 29], addressing breastfeeding problems (e.g., cracked nipples, breast engorgement, mastitis), insufficient child suckling, or attachment, a lack of lactation, and postpartum fatigue [29,30,31]. Traditional foods and herbs which were believed to increase milk supplies from the in-depth interviews and did not contradict the guideline were included for cultural relevance.

Most of the messages and library content highlighted the ability to have early initiation of breastfeeding and exclusive breastfeeding among all mothers regardless of delivery mode.

Step 3. Pre-test the notifications and library contents

The three focus group discussions with 24–36 weeks gestation mothers (18 mothers) were held for testing the app designs and the messages of the intervention group.

An example of scoring for each message and discussion is provided in Table 2. Overall, participants responded positively to the messages on the benefits of breastfeeding to newborn infants, particularly those on strengthening the immune system. The benefits of breastfeeding on increasing intelligence quotient /being smarter/to have better study were doubtful as an advertisement rather than based on evidence. Mothers were uncertain about the benefits of breastfeeding in preventing breast cancer and reducing anxiety and stress. However, uncertainty with the information would prompt them to open and read more in the library. Mothers suggested that “increasing mother-child bonding” was the most motivational factor for mothers to breastfeed their babies and should be included in the message.

Table 2 Example of testing messages scoring by mothers based on their preference (1 = lowest, 5 = highest)

To enhance the belief in having enough milk for the baby, mothers preferred messages which showed encouragement like “Do not panic if you do not produce enough milk on the first day. Colostrum is available since you are pregnant. Your baby needs only a small amount of milk each time” or “Relax and ensure that your baby is properly attached and suckling well, your body will produce more milk”. One mother said:

“I like this one most because many people don’t know this. I read a lot of documents before delivery and have experience with friends. However, the feeling of lacking milk and baby crying still push me to infant formula” (FGD2).

The messages had high-ranking, for example, “Do not discard colostrum, let your baby feed”, and “wash your hands with soap and water after changing a nappy and before handling your breasts”. “Start to breastfeed within the first hour or so of birth” was not at high ranking as it was affected by the mother-child separation from hospitals and they could do nothing.

Bonding between husband-wife and father-child was the most important motivated father for supporting the mother in breastfeeding and those messages were at high ranking than others. An example was “The more papa takes care of the baby; the more papa is fond of and loves the baby”. Most mothers thought that education on breastfeeding would be the best way for involving grandparents in support of breastfeeding. However, the messages involving grandmothers had a lower ranking compared with ones from other groups. The most liked message targeted at grandmothers was not directly related to breastfeeding: “Talk to your mother, mother-in-law about the food you want to eat after delivery”.

Messages on talking with health care providers were the lowest ranking among mothers. Most mothers were hesitant to talk with healthcare providers. A mother commented:

“Public hospitals will not support mothers. If you ask healthcare providers to do something, you would be scolded. Healthcare providers don’t like to be told what to do” (FGD1).

An example of library content was provided for mothers for discussion. They valued short and simple rather than evidence-based long and details content. The library information was internally reviewed by three Vietnamese researchers first and then by five external health educators on breastfeeding.

Step 4. Internal review, prototype testing, and revision of the app

Modifications were made based on focus group feedback. Prototype testing to detect errors was conducted before the app went live. A total of eight iOS and five Android beta versions had been tested and revised. Some major errors were fixed including unable to install the app, unable to activate the app, search the algorithm, and update the mother’s profile. Some minor errors were fixed including larger font size, higher contrast color filters designed, mixed English and Vietnamese, spelling mistakes, and adjusting pictures in the app to fit with the screen. After prototype testing and adjustments, BeBo is being currently evaluated in a randomized clinical trial with the target population described.