3.5.1. Social, cultural and environmental influences.

Social and cultural norms, including religion, family involvement, media influence and access issues, were perceived by MHCPs to influence a pregnant woman’s decision about influenza vaccination in pregnancy or access to antenatal care and thus the opportunity to be offered influenza vaccination.

In some settings, MHCPs perceived certain religious denominations restricted pregnant women from accessing antenatal care visits and hence uptake of the influenza vaccine [44]. In Kenya, when MHCPs were asked about what intervention they thought would help to address the religious restrictions toward vaccination, MHCPs proposed attending Sunday church services to discuss health concerns and provide information to pregnant women there to reach a larger demographic [44]:

“I asked her why she didn’t want to go for ANC services for her first born! I urged her that it was important to get vaccinated. She told me that their church doctrine restrains them from going to hospital. They get such instructions from their pastors.” [Kenya,44]

They reported that in societies where men have dominance over women, pregnant women were often restricted from receiving antenatal care by their husbands, which may have resulted in low rates of influenza vaccination’s uptake [44]. In societies where MHCPs found it difficult to persuade pregnant women to receive medication including vaccine, other family members who have power over these women’s decisions, such as mothers-in-law, were prohibiting pregnant women to take the vaccine [47]:

“She got married to guy who prevented her from going for [antenatal] clinic.” [Kenya,44]

“Sometimes, you just convince the pregnant women with a lot of effort, and then the mother-in-law won’t agree to let her take the medicine” [China,47]

In addition, anti-vaccine campaigns in the media can negatively influence the likelihood that a pregnant woman will receive vaccines [43]:

“Heard through the media, negative things through the media. So, what I have heard is ‘Oh, well…” [USA,43]

Geographical barriers to accessing healthcare services, and hence access to antenatal care including vaccination, including one example of a high crime rate area deterring pregnant women from attending clinics or necessitating police support to do so, as well as long distances and a lack of transportation to clinics. For instance, in rural areas, pregnant women avoided going to a health facility because of the long distance, which may have resulted in low uptake of influenza vaccines in those areas [44,45]:

“…There are a lot of municipalities with crime problems.” [El-Salvador,45]

“Distance to health facilities and lack of transportation was one of the major access issues perceived by providers to hinder maternal vaccine coverage” [Kenya,44]

3.5.2. MHCPs perceived views of pregnant women’s health materials and beliefs.

Across the studies, MHCPs discussed the factors that may influence pregnant women’s decisions toward the uptake of the influenza vaccine including hesitancy and lack of health literacy.

Despite the availability of influenza vaccine, MHCPs reported that pregnant women have more concerns about the influenza vaccine than the pertussis vaccine and are hesitant to receive the former due to a lack of awareness about the recommendations as well as concerns about the safety of the vaccine [41]. In addition, the idea of needing a vaccine to prevent influenza infection was not accepted by pregnant women who reported that the infection can be managed by natural remedies [47]:

“Women are maybe more hesitant to get the flu compared to pertussis…They think they’re going to have more reactions to it” [Australia,41]

“They stated that it would be even more difficult to convince pregnant women to accept a vaccine merely to prevent flu” [China,47]

MHCPs stressed the need for health materials about influenza vaccine during pregnancy in the form of posters, brochures or education hubs placed in health care facilities or provided to pregnant women to eliminate their concerns and promote vaccination [41,43,44]. Additionally, they discussed the need for health literacy that is translated into different languages and broadcasted through community radio stations [44]:

“I think if there was, like, an education hub type thing for vaccinations in pregnancy” [Australia,41]

“I think the information should be printed out in different languages and given to the community radio stations so that it can be explained to them.” [Kenya,44]

3.5.3. Interaction with MHCP.

Trust between MHCPs and pregnant women as well as MHCPs’ social position, communication approach to educating pregnant women, and pregnant women’s informed choices were interpreted as themes across the papers.

MHCPs reported that their ability to convince pregnant women to receive influenza vaccine was improved by having a good and trusting relationship with the pregnant woman [24,44].

“I have a good relationship with the patients and if I recommend it they probably would take it on board” [Australia, 24]

Bergenfeld et al. [44] explained that because of the MHCP’s authority and superior knowledge, pregnant women were more likely to trust MHCPs and follow their recommendations:

“Maybe sometimes they do not have that chance to say no because they look at me as their savior… and everything I tell them, they believe is right” [Kenya,44]

MHCPs should be able to effectively communicate and provide information/education to pregnant women [42,43]. MHCPs approached the introduction and promotion of influenza vaccination through one-to-one discussions to address pregnant women’s concerns and allowing them to ask questions [43]:

I will definitely base the conversation on kind of how they’re phrasing their questions and what their questions are. So I try to answer the question, and then may ask a couple questions back to just get a feel for what they already know about vaccinations, or what they already believe about it. And then we’ll kind of reframe it based on their system of beliefs. [US,43]

Using passive language in the discussion with pregnant women to frame the significance of influenza vaccination during pregnancy, using this language with pregnant women makes them feel that taking the vaccine is the right thing to do as it is of advantages for themselves and their new-borns [41]:

“It is recommended. The research shows that it is advantageous.” [Australia,41]

Additionally, influenza vaccination administration was framed as a choice for pregnant women rather than the MHCPs’ recommendation. MHCPs’ role was to provide advice only, rather than share in the decision making [24,43,46]. However, Wilson et al. [46] reported that influenza vaccination was not recommended by some MHCPs but merely mentioned:

“We do not push it. We do not insist. We just advise them. If they accept that’s fine” [Australia,24]

Workload and time limit were factors reported by MHCPs as limiting influenza vaccination discussion with pregnant women [42,44]:

“Maybe when a health care provider is in a hurry or is being overworked, you may find a long queue at the ANC waiting for vaccination. The nurse there may not have time to discuss much with every client about the vaccines. Sometimes they issue orders for the mothers to queue and get vaccinated. These are situations which may happen when there are several mothers at the clinic. This can cripple vaccine uptake since there is no time for explanations” [Kenya,44]

“The doctors are very busy and so for example in the private clinic we run at capacity so we’re turning women away, so we basically have to apply um err almost triage principles to how we run our consultations but we do have a um midwife there with us who is our personal sort of assistant if you like. So things like breastfeeding and err analgesia in labor and vaccinations although I don’t know if they mention vaccinations I’ll be honest. We tend to delegate to them. The longer we make the consultations basically the less patients we can see.” [Australia,42]

3.5.4. MHCP’s Knowledge and attitude.

MHCP knowledge and attitude about influenza vaccine during pregnancy were identified within this theme. MHCPs showed variations in their perceptions of the risks associated with influenza infection during pregnancy [24,41,44]. There was a lack of knowledge about influenza vaccination recommendations during pregnancy [24]. Thus, influenza vaccine did not appear to be a priority among MHCPs compared to other vaccines, and when it is promoted, it is to protect the mother rather than the foetus [41]:

“I think with the number of people (pregnant women) who catch the flu and the number of people who don’t have any problems with it….I see it’s a small amount of risk involved” [Australia,24]

“Generally, pertussis vaccination was presented in terms of protecting the baby, while influenza was primarily to protect the mother.” [Australia,41]

Three studies included discussions of MHCPs’ attitudes [24,45,47]. Some MHCPs expressed that they need to assure themselves about a vaccine before recommending it to pregnant women [44]. Others reported that there are many strains of influenza viruses, so they had doubts about the effectiveness of the vaccine [47]:

“We, the health care personnel, are the main factor [in low vaccination acceptance]…first, we have to be convinced ourselves in order to convince the population.” [El-Salvador,45]

3.5.5. Local healthcare system.

In order to enhance the uptake of influenza vaccine during pregnancy, MHCPs recommended professional training and education for them, dedicated vaccination teams, improved record keeping and electronic vaccination prompts.

Professional education and training workshops or campaigns for MHCPs would help to promote the discussion of maternal influenza vaccination by increasing MHCPs’ knowledge and hence their confidence [41,44]. Continuous professional education about vaccinations other than tetanus toxoid was needed among MHCPs to provide details on vaccines’ side effects and efficacy [24]. This approach would prepare MHCPs to be better advocates for vaccinations and to address pregnant women’s concerns and hesitations:

“If you do not update me properly, it will be of no use even if [a new vaccine] is brought to the facility. It will be available but I will not give it out, not because the patients are not asking for it, but because it is me who is not interested in giving it out” [Kenya,44]

“Those who had completed additional training reported feeling confident in their knowledge and ability to discuss vaccines” [Australia,41]

A lack of standardisation for MHCPs regarding influenza vaccine delivery during pregnancy was reported in four studies [41–43,46]. Some MHCPs felt that they were not responsible for discussing influenza vaccination with pregnant women and that this is their GP’s responsibility [42]. However, MHCPs reported that vaccination discussion and delivery is a nurse’s responsibility, as they have more time to discuss this with pregnant women [43]:

“We don’t have any role in that [maternal vaccination]. We don’t organize that, I usually send them off to their GP. If you want influenza vacs you can get it through your GPs the best place.” [Australia,42]

“A nurse ’cause they would have some clinical knowledge and probably the time to do it. I don’t see a physician doing that here. Just as far as timing. Um, and then a practice manager, I don’t know that they would have all the clinical knowledge, and all the information.” [USA,43]

The need for a vaccination champion who is managing and creating enthusiasm for vaccination campaigns as well as encouraging better communication about vaccination between MHCPs, was discussed in two studies; it was perceived that vaccine champions may increase the delivery of maternal influenza vaccine [43,46].

In addition, MHCPs suggested using reminders such as a checklist, sticker or electronic prompt to discuss the influenza vaccine with pregnant women [24,41,43]. Also, they reported an absence of influenza vaccination’s history reference in documentation and lack of mechanism for documenting the uptake of the vaccination or to follow up [Australia,42]:

“In addition, immunization history is not part of the lengthy medical, psycho-social, surgical, and family history taken at a woman’s first antenatal visit.” [Australia,42]

3.5.6. National policy and practice.

Setting a national policy and developing guidelines, centralizing vaccine information and providing influenza vaccine for free would enhance MHCPs provision of influenza vaccination discussion, recommendation and delivery during pregnancy.

A lack of policies and guidance on vaccinations has resulted in some MHCPs being unaware about recommendations for influenza vaccine delivery during pregnancy [24,42]. Although, in countries where vaccination policies did exist, some MHCPs were not informed about existing policies and guidelines [47]:

“Yes, well, it was recommended from the health department to do so I would assume that the information is accurate and there’s no risk in doing it so I’m happy to follow that” [Australia, 24]

“We have never been informed or required to recommend influenza vaccine to pregnant women. We will do the work only when higher level administrative sectors require us to do so.” [China,47]

Pregnant women’s geographical mobility and lack of a consistent information system made it difficult for MHCPs to keep track of pregnant women’s vaccination history [44]:

“This was linked to the notion that women often move during their pregnancy, leaving gaps in their medical records that are difficult to address without an integrated system.” [Kenya,44]

MHCPs reported that the private sector’s profiting from influenza vaccinations may affect the delivery of the vaccine [44]. Therefore, MHCPs sent pregnant women to get their vaccines from free public hospitals [45]:

“Private hospitals are established to make profits. The charges may keep them away” [Kenya,44]

Barriers to maternal influenza vaccination as perceived by MHCPs.

Provided that a woman was able to access antenatal care, then barriers to influenza vaccination included MHCPs’ workload, time constraints, MHCP’s perceptions of women’s concerns about influenza vaccine and a lack of knowledge on the part of MHCPs in relation to influenza vaccine.

Social, cultural and environmental influences, including religion, have been widely discussed within the evidence base as a barrier to vaccination in general [48–51]. The religious objection against vaccination has many explanations, such as interference with the natural order by restricting the natural course of events, or because the vaccine itself does not meet religious dietary laws [51].

Anti-vaccination campaigns have been shown to undermine the authority of HCPs toward vaccinations [43]. A 2018 study of 314 pregnant women found that 22% showed hesitancy toward the influenza vaccine because of negative campaigns in the media [16].

MHCPs’ knowledge varied across the different studies in our synthesis. For example, Maher et al. [24] showed that limited knowledge about influenza vaccination among MHCPs would result in either not recommending the vaccine or recommending it with varying levels of precision and confidence.

Workload and time constraints are two main barriers to influenza vaccination discussion and delivery among HCPs. The results of this qualitative evidence synthesis reflect evidence from previous quantitative studies; because influenza vaccination is not a priority for most HCPs, workload and time constraints have led to neglect of its discussion and recommendation [22,52].

Facilitators to maternal influenza vaccination as perceived by MHCPs.

Facilitators to influenza vaccination included trust and a good rapport between MHCP and pregnant women, clear national guidelines and education and training for MHCPs.

Bergenfeld et al. [44] mentioned that a fiduciary relationship may exist, in which patients trust that their HCP is better informed about their health and consequently transfer their health responsibility to the MHCP [53]. Our qualitative evidence synthesis showed that pregnant women’s trust in MHCPs to make decisions about vaccination provides the opportunity to preserve and leverage maternal acceptance for existing and new vaccines. However, the amount of trust that is usually present between pregnant women and MHCPs is influenced by the duration of that relationship and the HCP’s knowledge [24]. In addition, how the vaccination discussion is initiated can impact pregnant women’s vaccination uptake decision [54]. For instance, the presumptive or motivational communication approach, when supported by evidence, can positively influence pregnant women’s decisions regarding the uptake of the influenza vaccine [41,43]. This finding is in agreement with a recent systematic review that studied qualitative and quantitative evidence about factors that influence vaccination decision making among pregnant women; this reported that the odds of influenza vaccine uptake were 10 to 12 times higher among pregnant women who had received a recommendation from their HCPs [55]. Taking informed consent for influenza vaccination from pregnant women might provide a communication opportunity between MHCPs and pregnant women to discuss the vaccination.

The presence of clear national guidlines would enhance MHCPs to discuss and recommend vaccination to pregnant women, as it would promote their responsibility toward the delivery of the vaccination and avoid them of being held liable to the possible adverse events of the vaccination [24,42,47].

Knowledgeable HCPs have shown more confidence discussing and recommending influenza vaccines [24,41,44]. Evidence based and effective training and education is a necessity for MHCPs to be aware of the importance of vaccinations as well as enabling them to discuss any hesitations that they may have, in order to cope with the expectations of the system and the concerns of pregnant women.

Suggestions for interventions to increase influenza vaccination.

Although the idea of a vaccination champion was identified by both Frew et al. [43] and Wilson et al. [46], it is not widely applied in clinical practice. Previous studies have shown that vaccination champions can improve vaccination rates [56,57].

The range of MHCPs in the studies in this review were heterogeneous. However, as midwives spend more time with pregnant women than other MHCPs, they are ideally placed to be more engaged with vaccination promotion campaigns and programmes [41,46]. Midwives should receive appropriate vaccination administration training so that pregnant women can receive their vaccines when they are recommended rather than inconveniencing them with extra appointments [41,46].

The WHO initiatives to increase the uptake of influenza vaccination during pregnancy is represented by the global expert group Measuring Behavioural and Social Drivers of Vaccination (BeSD) who has adopted a model for vaccine hesitancy [58]. This model identifies three classifications of hesitancy: a) poor contextual guidance from authority figures, including influential leaders and persons; b) experiences relating to various cases of poor healthcare, either from the media or within social groups; and c) complications related to vaccines and negative interactions with healthcare providers [58]. The WHO model was designed to help MHCPs tackle vaccination hesitancy. There is overlap between the WHO model and our review findings in terms of how social factors and the media affect pregnant women’s decisions to vaccinate. Another overlap is with the need for good communication between MHCP and pregnant women to address pregnant women’s concerns about vaccination’s safety, which would increase the uptake of maternal influenza vaccine.