In this sample of women, we found two thirds of pregnancy outcomes are normal live births. The proportion of adverse birth outcomes was significantly higher for births occurring at home than in hospital, but similar among all women from the two geographically diverse regions and who were different in demographic characteristics. The difference in characteristics in this study provide a good comparison with the general population as our results are similar with findings of the 2014 Kenya demographic health survey(21). These results also ascertain possibility of observing equal distribution of safety outcomes across maternal populations from the different geographical regions in Kenya on introduction of a new maternal vaccine.
We found preterm births were the most common adverse birth outcomes in this study accounting to nearly 22% (490/2219) of all infants. Additionally, 2% of the preterm births in this population, occurred within the gestational age period not likely to have an optimum level of protective antibody (10) after maternal vaccination. This implies that, this group of infants will be susceptible to severe RSV disease and might require use of other strategies such as prophylactic monoclonal antibodies for prevention (35, 36).
Tertiary level of education, eclampsia, gestational diabetes, delayed ANC initiation, number of ANC visits, being multiparous and home delivery were found to be significantly associated with adverse birth outcomes in this study. Eclampsia has been found to cause deterioration of maternal conditions which result into adverse foetal outcomes such as low birthweight and still births (37). In Ethiopia, adverse neonatal outcomes such as macrosomia, preterm births and large for gestational age was found to be significantly higher among newborns from mothers with gestational diabetes (38), which is similar to findings in this study. Women with low level of education might belong to a low socio-economic status group and could not afford the cost of care therefore, missing uptake of preventive services or skilled care during delivery (39). It has also been found that cultural practices during home delivery like massaging of the abdomen to align the baby, which is very common among indigenous populations along the coastal part of Kenya are associated with placenta praevia and abruption, asphyxiating the foetus and increased chances of trauma to the baby and premature delivery (39). Perhaps, a consideration to integrate strategies directed towards mitigating against causes of adverse pregnancy outcomes such as proper management of high-risk pregnancies, educating traditional birth attendants on risks of some of the cultural practices during delivery might be worth an undertaking.
We found 29.8% of births in Kilifi and 6.0% in Siaya still occurred at home. However, our results show a decline in proportions of home births as observed prior to free care during the 2014 Kenya demographic health survey (47% in Kilifi vs 27% Siaya) (21); which could be attributed to current government initiatives focused to achieve universal access to maternal and child health services (23). These initiatives include, “Beyond Zero” (22) which was launched in 2014, by the first lady in Kenya, and aims to prevent maternal and infant deaths by providing mobile clinics to provide care to pregnant women who have no access to hospitals during delivery. In addition, the government of Kenya through the Ministry of Health in 2016, also launched another initiative known as “Linda Mama” (23) which ensures pregnant women and infants have access to free, quality and affordable maternal and child health services by use of a public funded health insurance scheme. The impact of these initiatives seems evident through the observed reduction of home deliveries in this study.
Among the women who delivered at home, 165 (69%) attended ANC and had booklets available, indicating they received ANC services. Multiple ANC visits in this study were also found to be associated with less adverse birth outcomes. It is worth noting that, high rates of ANC attendance among pregnant women enhances uptake of interventions, ensures high vaccine coverage (40) which mitigates against poor outcomes during and after delivery. However, full use of ANC and services alone does not prevent all adverse birth outcomes even in the highest resource settings. This is because, most pregnancy complications occur during delivery and can result in poor pregnancy outcomes (41) which can result into mis-interpretation of safety outcomes of a maternal vaccine. In a survey to find out birth preparedness and complication readiness among Kenyan women showed only 11.4% (59/519) were well prepared for births and its complications during pregnancy (42). Initiatives such as provision of night transport services to pregnant women during labour, equipping lower levels health facilities with qualified staff, training, oversight and resources to handle emergencies which will encourage pregnant women utilize hospital services to reduce risks associated with home deliveries, will be reasonable, but should not be a barrier to vaccine rollout. Procedures to detect adverse outcomes should be put into place during trial or within a managed phase iv rollout setting, to provide a reliable system for validating effectiveness and safety of a new maternal vaccine.
The choice of place for delivery was found to be associated with maternal age, facility for ANC attendance, religion, parity and education level. Older women were more likely to deliver at home than in hospital and this is perhaps a result of experience in having previous successful deliveries or uncomplicated pregnancy (39). Similarly, women who have had multiple pregnancies were more likely to deliver at home than in hospital while higher education level was associated with less home delivery as observed in other studies in coastal Kenya (39, 43). A study in north eastern Kenya, found male doctors attending to women in labour prevented pregnant women from delivering in hospital (44) because of religious beliefs and in this study, we also find Muslim women were more likely to deliver at home than in hospital. The role of influencers such as spouse, healthcare providers and relatives in determining place of delivery is also of much importance and might require empowering of pregnant women in decision making. Introduction of new interventions among these pregnant women may also need consideration of the socio-cultural factors such as religion, individual perceptions on births or cultural beliefs to ensure maximum uptake.
Majority (99%) of pregnant women in this study reported they would accept the maternal RSV vaccine despite a few having concerns that the vaccine might not be safe. Perceptions about risks associated with a vaccine might result to high rates of vaccine refusals which is likely to affect the overall effectiveness. For instance, a study in Quebec found a belief that a H1N1 influenza vaccine was not adequately tested resulted in its low uptake among pregnant women (45). Most pregnant women appear to have more trust on their health care providers regarding information on interventions available and their uptake within health facilities (46). For a successful implementation of the maternal RSV vaccine program in this setting, we recommend integration of sensitization and education sessions between health care providers and pregnant women perhaps through health talks and information brochures within ANC platforms to create awareness about the safety and efficacy of the new maternal vaccine, resolve doubts and increase confidence before its introduction.
There are some limitations in this study. HIV status was not collected among these women and, proportions of adverse birth outcomes attributed to HIV infection and how HIV would likely have altered the observed associations of other variables in multivariable analyses. The data is drawn from a sample of women from two out of the 47 counties and may not be representative of all Kenyan women. Stillbirths that occur in the community often go unreported and could have also been missed in this study. Hospital enrolment of some of the participants may represent a bias. However, our study provides important baseline data on birth outcomes which has often been missed by studies involving a small sample size of women and gives a detailed description of the baseline proportions of adverse birth outcomes and associated factors in this setting which can guide validation and monitoring of the safety outcome of a new maternal vaccine program.