Mothers’ Impressions and Beliefs About Taking a Booster Dose for COVID-19 Vaccine During Pregnancy and Lactation

Objectives: This study aimed to explore perceptions and willingness to get coronavirus disease 2019 (COVID-19) booster vaccination among pregnant and lactating women in Jordan. Methods: A cross-sectional study using a 29-item web-based questionnaire was conducted. Sociodemographic characteristics, vaccine acceptance, confidence in the booster dose of COVID-19 vaccine, perception of risk for COVID-19, and acceptance to participate in COVID-19 booster vaccine clinical trials were prospectively evaluated. Logistic regression was used to identify factors that might affect the participants’ acceptance of a COVID-19 vaccine and their willingness to enroll in clinical trials of a booster dose of COVID-19 vaccine. Results: Among all participants (pregnant and lactating women, n = 584), 328 (56.2%) intended to receive the booster dose of the COVID-19 vaccine. Predictors of booster dose acceptance were a medical-related degree (OR 1.62, CI 1.06-2.5, p = 0.028), income (OR 0.677, CI 0.52-0.88, p = 0.004), living residency (OR 0.44, CI 0.32-0.60, p < 0.001), knowing pregnant/lactating women previously infected with infectious microbe (OR 1.539, CI 1.07-2.23, p = 0.022), commitment to immunization for children (OR 3.01, CI 1.03-8.82, p = 0.044), receiving an influenza vaccine (OR 1.46, CI 1.04-2.05, p = 0.031), and worried about infectious microbes (OR 1.32, CI 1.15-1.52, p < 0.001). Among participants, only 22.9% were willing to participate in clinical trials of the booster dose of COVID-19 vaccine. The biggest motivator for participation was the participants’ desire to help find the best vaccine during pregnancy/lactation (57.5%) while the main barrier towards participation was not wanting to expose themselves and their babies to more side effects (88.0%). Conclusion: This study reported reasonable acceptance of vaccination in a sample of pregnant/lactating women. Vaccination hesitancy for the booster dose was in-line with similar studies on the primary series around the globe, but the willingness to participate in clinical trials was lower than non-pregnant/non-lactating women.


Introduction
Pregnant women with coronavirus disease 2019  infection are at increased risk for pregnancy complications, such as preterm birth and pregnancy loss, and neonatal intensive care unit admission [1]. Moreover, pregnant women may be at higher risk for COVID-19-related scenarios, such as intensive care unit admissions, mechanical ventilation, extracorporeal membrane oxygenation, and death compared with nonpregnant women [2].
Due to limited data concerning maternal-infant transmission of COVID-19 during breastfeeding, literature on breastfeeding management in confirmed COVID-19 mothers did not recommend breastfeeding in suspected and uncured cases and also while taking lopinavir/ritonavir treatment [3]. In addition, the Union of European Neonatal and Perinatal Societies advises mothers who are too sick to manage their babies separately with freshly expressed breastmilk to avoid any harm to the babies [4].
Vaccination during pregnancy and lactation is common to prevent both maternal and infant morbidity caused by other infectious diseases, such as influenza and pertussis. The clinical data on safety and efficacy of such vaccines are abundant [5,6]. However, pregnant and lactating women were excluded from the initial COVID-19 vaccine trials worldwide; thus, data to guide vaccine administration to such groups are lacking. The Centers for Disease Control and Prevention (CDC), the Society for Maternal-Fetal Medicine, the American College of Obstetricians and Gynecologists (ACOG), and the American Academy of Pediatrics have each issued guidance supportive of offering COVID-19 vaccines to pregnant women [7][8][9]. The Academy of Breastfeeding Medicine states that potential risks of COVID-19 infection should be weighed against the potential benefits of neonatal protection via passive transfer of antibodies from breast milk [10].
Additionally, in 2021, the ACOG recommended booster doses (third vaccination dose) for pregnant and postpartum women due to their increased risk of COVID-19-related consequences. Previous trials on pregnant women found that booster dose was associated with higher maternal antibody levels and thus lower risk for severe COVID-19-related outcomes [11] as well as a stronger level of protection for young infants compared to the second dose [12].
Even though recent guidance indicates that COVID-19 vaccines including booster doses should not be withheld from pregnant and lactating women, there is no consensus regarding vaccination during pregnancy/lactation and vaccine hesitancy among women still existed.
In January 2021, Jordan began its vaccination campaign against COVID-19, with healthcare workers and the elderly prioritized for the first shots. Thereafter, in September 2021, the Jordan Ministry of Health authorized the booster shot for people 60 years old and above, the immunocompromised, including those with chronic illnesses, and health workers [13]. The present work was performed at the time of launching the booster dose to public and aimed to explore perceptions and willingness to get COVID-19 booster vaccination among pregnant and lactating women in Jordan. These data might be used to address vaccine hesitancy and refusal driven by knowledge gaps since, until recently, there was a misunderstanding and insufficient knowledge about COVID-19 risks, management, and vaccination during pregnancy and lactation among women in Jordan [14].

Materials And Methods
This was a cross-sectional study conducted from November 2021 to January 2022 among pregnant and lactating women in Jordan. The sample population was a convenience sample targeted through social media platforms, i.e., Facebook groups. A minimum of 383 patients based on maximum annual deliveries of 80,000, 5% margin of error, 95% confidence level, and 50% response distribution were required. Any pregnant and lactating woman living in Jordan at the time of the study was eligible to participate. A detailed explanation about the study was provided to potential participants and consent about anonymity of the survey and voluntary participation was then obtained for each participant. The used platform allowed participants to move through sections only when their answers were completely obtained. The study was approved by the Ethical Approval Committee of the Institutional Review Board of Yarmouk University (approval number: IRB/2021/2).
The questionnaire of this study was structured based on a broad literature search using MEDLINE/PubMed and Google Scholar. Most relevant articles have been retrieved and then the questionnaire was designed [15][16][17][18]. The questionnaire was evaluated by a group of experts, then it was piloted on 30 subjects to provide feedback about the relevance, clarity, and comprehensibility of the questions (Appendix). The survey data was analyzed using social science software, SPSS® version 26 (Chicago, IL: SPSS® Inc.). The mean, standard deviation, frequencies, and percentages were used for continuous and categorical variables as needed. Analytical graphs were used as appropriate. Logistic regression was used to identify factors that might affect the participants' acceptance of a COVID-19 vaccine and their willingness to enroll in clinical trials of a booster dose of COVID-19 vaccine. Statistical significance was at a p < 0.05.

Demographic characteristics
Among 584 respondents, 37.3% (n = 218) and 59.9% (n = 350) were pregnant and lactating, respectively, at the time of taking the survey ( Table 1). The mean age of all respondents, both pregnant and lactating mothers, was 29.7 years (SD = 4.8). Among participating women, 87% (n = 508) had at least one child. The majority had a Bachelor's degree (68.2%) and 23.8% (n = 139) had a health program degree.

General vaccines acceptance
The majority of participants (n = 565) stated their likelihood to vaccinate their children with routine national immunization program. In addition, the results showed that 84.1% and 84.6% believed that such vaccines are safe and effective, respectively. On the other hand, only 26.4% (n = 154) of participants received a previous seasonal influenza vaccine.

Predictors of booster dose of COVID-19 vaccine acceptance
The associations between the booster dose of COVID-19 vaccine acceptance during pregnancy/lactation and potential predictors showed that the factor of monitoring the COVID-19 news on media was slightly linked to booster dose acceptance. On the other hand, the strongest predictors of COVID-19 vaccine booster dose acceptance were among women who are having a health-related degree, have higher income, living in middle or South Jordan, being a lactating woman, know pregnant/lactating women previously infected with COVID-19, committed to routine immunization for children, receiving seasonal influenza vaccines, and worried about COVID-19 (   [19,20].
The strongest predictors of COVID-19 vaccine booster dose acceptance among participants were among women who are having a health-related educational level, higher income, living in Middle or South Jordan, being a lactating rather than pregnant woman, knowing pregnant/lactating women previously infected with COVID-19, committed to routine immunization for children, received seasonal influenza vaccines, and worried about COVID-19.
Although evidence confirming elevated risk from COVID-19 infection in pregnancy was reported, pregnant women have been excluded from most studies of COVID-19 treatments as well as from COVID-19 vaccine trials [21]. This exclusion could be the encouragement needed for pregnant/lactating women with a healthrelated profession to accept COVID-19 vaccines. It has been previously reported that some professions, such as dentists, nurse midwives, mental health counselors, and therapists had higher associations of vaccine acceptance [16].
A wide range of vaccine acceptance rate was previously reported in many countries based on income; those who live in low-income countries were found to have lower acceptance rates than those who live in higherincome countries [17]. These results on the primary series of COVID-19 vaccine are consistent with the findings of our study on the booster doses where women living within high-income families were more likely to accept.
The present study found that mothers who live in the middle and south regions of Jordan had higher acceptance rates of a booster dose of COVID-19 vaccine. This could be justified by their belief in the importance of vaccines to people living in these tourist sites of the country as tourism destinations were negatively affected by the COVID-19 pandemic, with almost 100 travel agencies, 80% of hotels (three stars and below), and 800 restaurants and local cafes closed. Moreover, around 14,000 employees lost their sources of income, many of them live and work at tourist sites [22].
Our results showed that pregnant respondents were more likely to decline vaccination compared to lactating respondents. This finding is in line with a previously published survey on vaccine acceptance [16]. The later study found that non-pregnant participants were most likely to accept vaccines with breastfeeding participants the second most likely while pregnant participants had the lowest rate of vaccine acceptance. This could be the result of pregnant women worrying that the vaccine could cause harm to them or their fetuses. In addition, those who know pregnant/lactating women previously infected with COVID-19 had higher vaccine booster acceptance. This could be due to their concerns about having the same experience and the possibility that they will be at risk of contracting COVID-19 or becoming severely ill from it.
Globally, routine immunization for children is relatively high and for instance, 83% of the world's children receive full doses of the diphtheria-tetanus-pertussis vaccine (DTP3) every year [23]. Similar results were found in the present study where 96.7% indeed have their children fully vaccinated; without missing any obligatory ones. This indicates that women who accept their children to be vaccinated value vaccines including booster doses. Also, those who receive seasonal flu vaccines had a higher acceptance of a COVID-19 vaccine booster.
The results also showed that the perceived risk of COVID-19 for pregnant/lactating women, as measured by their worries toward COVID-19 was a strong predictor for acceptance of having COVID-19 vaccine booster dose. Even though this factor is being influenced by the current pandemic status, it seems that it has previously affected vaccine hesitancy [24].
The study also showed that a low proportion (23%) of participants had willingness to participate in clinical trials for COVID-19 vaccine; which was lower than the rate reported in France and China [18,25]. The top reason for pregnant/lactating women to refuse enrollment in clinical trials for COVID-19 booster vaccination was their worries of being further exposed to more harmful side effects on themselves and their babies. The same reason was found for COVID-19 vaccine reluctance among pregnant/lactating mothers in previous studies [15,16]. One of the most common reasons for declining vaccination according to Sutton et al. included fear of harming the pregnancy [16].
Apart from the limitations related to online surveys, where only those who had access to the technology, resources, and ability to navigate the internet were approached and enrolled, the study included enrollment of women in any trimester of pregnancy and any time during the lactation period which limits the generalizability to each category. Although the number of respondents was not large, it was very diverse. Furthermore, vaccine acceptance levels among people might change over time as more data will be accrued.

Conclusions
This study reported 56.2% acceptance of COVID-19 booster dose vaccination in a sample of pregnant/lactating women. Since booster vaccine against COVID-19 in pregnancy and during lactation can further control the burden of the disease and decrease morbidity and mortality during pregnancy/lactation, strategies to reduce vaccination hesitancy among the unvaccinated pregnant/lactating women as well as offering boosters to all already-vaccinated ones should be implemented to accomplish efficient COVID-19 immunization among this population. Relying on that and furthermore, vaccination trials in Jordan for pregnant/lactating women with a focus on short-and long-term safety and effectiveness data from vaccination during pregnancy and lactation periods are needed.

Dear participant
Researchers from different Jordanian Universities are carrying out a research project with the purpose to assess the acceptance of COVID-19 booster dose vaccination among pregnant and lactating women in Jordan.
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The procedure involves filling an online survey that will take approximately 10 minutes. Your participation in completing this survey is highly appreciated.
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Additional Information Disclosures
Human subjects: Consent was obtained or waived by all participants in this study. Institutional Review Board of Yarmouk University issued approval #IRB/2021/2. Animal subjects: All authors have confirmed that this study did not involve animal subjects or tissue. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work.