EBCOG position statement: Vaccination in pregnancy

Impact of Infections During Pregnancy on Transplacental Antibody Transfer

Vaccination in pregnancy is important to protect the mother and fetus from infectious diseases. The transfer of maternal antibodies across the placenta during pregnancy can continue to protect the neonate for several months after birth while the neonatal adaptive immune system develops. Several pathogens have been shown to impair the transplacental transfer of maternal antibodies, including human immunodeficiency virus, malaria, the severe acute respiratory syndrome coronavirus 2, and cytomegalovirus. This review discusses the mechanisms contributing to decreased transplacental antibody transfer in the setting of maternal infections, such as changes in antibody glycosylation profile, maternal hypergammaglobulinemia, and placental injury. The frequency of epidemics is increasing, and pregnant people are more likely to become exposed to novel pathogens now than they were in the past. Understanding the mechanisms by which infectious diseases impair maternal-fetal antibody transfer is important for pandemic preparedness to maximize the impact of maternal vaccination for child health.

FIGO Preconception Checklist: Preconception care for mother and baby

The preconception period is a unique and opportunistic time in a woman's life when she is motivated to adopt healthy behaviors that will benefit her and her child, making this time period a critical "window of opportunity" to improve short- and long-term health. Improving preconception health can ultimately improve both fetal and maternal outcomes. Promoting health before conception has several beneficial effects, including an increase in seeking antenatal care and a reduction in neonatal mortality. Preconception health is a broad concept that encompasses the management of chronic diseases, including optimal nutrition, adequate consumption of folic acid, control of body weight, adoption of healthy lifestyles, and receipt of appropriate vaccinations. Use of the FIGO Preconception Checklist, which includes the key elements of optimal preconception care, will empower women and their healthcare providers to better prepare women and their families for pregnancy.

Vaccination against influenza in pregnant women in a maternity hospital in the Czech Republic in the season 2020-2021

OBJECTIVES

Pregnant women are among the priority groups to receive influenza vaccines in the Czech Republic since 2011, data on vaccination coverage are not yet available. The aim of the study was to determine the influenza vaccination coverage (IVC) and provide source data for further activities.

METHODS

A prospective observational study was performed in a large maternity hospital in Prague. The self-completed questionnaire was distributed to 5,475 pregnant women between September 1, 2020 and August 31, 2021. Questions included maternal sociodemographic characteristics, influenza vaccination status and sources of maternal vaccination recommendations during pregnancy.

RESULTS

A total of 4,617 completed questionnaires have been analysed. The median age of study participants (N = 4,592) was 33 years (range: 18-51 years). The majority (69.7%) of women had completed their university education, most women were childless (58.5%) or had one child (32.5%) before the start of the study. Less than 2% of women reported being vaccinated against influenza during their pregnancy (1.5%; 95% CI, 1.1-1.9%). Only 21% of women knew that it's possible to get vaccinated against influenza during pregnancy. Participants considered influenza vaccination in pregnancy as important (3.3%), useful (41.1%) and useless (44.4%). Out of 959 pregnant women who had information about influenza vaccination during pregnancy, only 6.9% were vaccinated, while among those who did not have this information, 0.1% were vaccinated during pregnancy (p < 0.001). The most frequent source of information was Internet, then media and a general practitioner.

CONCLUSIONS

The IVC during pregnancy in our study was extremely low. In order to improve IVC among pregnant women, it is necessary to increase awareness of recommendations and vaccination options among the public and professionals and incorporating vaccination recommendation in routine antenatal practice.

Seroprevalence of SARS-CoV-2 antibodies among first-trimester pregnant women during the second wave of the pandemic in India

OBJECTIVE

Data on the immune response to SARS-CoV-2 during pregnancy are lacking and the potential role and effect of SARS-CoV-2 vaccination in pregnancy is yet to be completely investigated.

METHOD

This is a cross-sectional observational study wherein pregnant women were tested for SARS-CoV-2 immunoglobulin M and immunoglobulin G levels, irrespective of their infective status or presence or symptomatology.

RESULT

Of the 220 pregnant women tested, 160 (72.7%) were SARS-CoV-2 IgG positive, 37 (16.8%) were SARS-CoV-2 IgM positive and 27 (16.9%) were both IgG and IgM positive. The average antibody titer found was 10.49 BAU/ml (±14.0) and 0.6 (±0.55) for anti-SARS-CoV-2 IgG and IgM non neutralizing antibodies respectively. ROC analysis for SARS-CoV-2 IgG positivity showed a cut-off value of 1.19 with a sensitivity of 99.3% (0.99 AUC, 95% CI) and specificity of 98.3% (0.99 AUC, 95% CI), respectively. Similarly, ROC analysis for SARS-CoV-2 IgM positivity showed a cut-off value of 1 with a sensitivity of 97.3% (0.99 AUC, 95% CI) and specificity of 98.9% (0.99 AUC, 95% CI), respectively.

CONCLUSION

First trimester sero-molecular screening suggests a high prevalence of COVID antibodies in the study population of pregnant women in the first trimester, without the patients being symptomatic.

Experts' Opinion for Improving Pertussis Vaccination Rates in Adolescents and Adults: A Call to Action

This article highlights the importance of diphtheria-tetanus-acellular pertussis (with reduced antigen content, dTap) vaccination in preventing pertussis, a respiratory infection that is still widespread and easily transmitted. In particular, it highlights the need to receive a booster vaccination throughout life to maintain high antibody levels, which decrease through time. This document collects the opinions that emerged from the comparison between major Italian experts in the field of vaccination. This working group was created to promote a "call to action", aimed at raising awareness among all institutions, public health authorities, and health workers involved in the vaccination process, about the importance of dTap vaccine administration and with the mindset of implementing the strategic vaccination plan provided by the National Vaccine Plan (NVP). In fact, despite this vaccine being included in the NVP, there are some issues attributable to the practice of vaccination (local health authorities, vaccination centers, occupational health services, gynecology centers, societies of work). Therefore, it is necessary that the Ministry defines the vaccination coverage objectives, identifies the groups of subjects who should receive the booster vaccine (subjects exposed to greater risk of infection, subjects over 60, pregnant women), and applies all the necessary measures to encourage the implementation of this practice.

Suboptimal Vaccination Administration in Mothers With Inflammatory Bowel Disease and Their Biologic-Exposed Infants

BACKGROUND

Pregnant women with inflammatory bowel disease (IBD) are at increased risk of developing complications from vaccine-preventable infections. We investigated the factors influencing vaccine administration in pregnant women with IBD and their infants, in addition to the safety of vaccination in the infants.

METHODS

This retrospective cohort study identified individuals from a tertiary referral clinic whose records were linked to a provincial vaccine database. We conducted χ 2 tests, Fisher exact tests, and logistic regression adjusting for age and disease duration to compare vaccine administration by medication class. Potential rotavirus vaccine adverse events were determined in infants of women with IBD.

RESULTS

We included 303 pregnant women and 262 infants. Vaccines were administered to women on biologic therapy as follows: hepatitis B virus (82.9%), diphtheria-tetanus-pertussis (82.1%), and hepatitis A virus (49.3%). The influenza vaccination was provided peripartum in 50.7% of patients. The measles-mumps-rubella-varicella vaccine was provided to 89.3% of women before biologic initiation. Women treated with a biologic (adjusted odds ratio, 2.50; 95% confidence interval, 1.39-4.35) or immunomodulator (adjusted odds ratio, 4.00; 95% confidence interval, 2.22-7.69) were more likely to receive the Prevnar 13 and Pneumovax 23 vaccines than were unexposed individuals, but the overall proportion vaccinated was low (Prevnar 13, 35.7%; Pneumovax 23, 39.3%). At least 90% of infants received the measles-mumps-rubella-varicella vaccine and inactivated vaccines. Fourteen biologic-exposed children (19.2%) received the live rotavirus vaccine with no significant differences in adverse events compared with biologic-unexposed infants (7.1% vs 8.2%, P = 0.99).

CONCLUSIONS

Better education surrounding vaccine recommendations is required for both health care providers and individuals with IBD given poor pneumococcal, hepatitis A virus, and influenza vaccination rates. Inadvertent administration of the rotavirus vaccine in biologic-exposed infants did not result in more adverse events, raising the possibility of safety.

Longitudinal analysis of antibody response following SARS-CoV-2 infection in pregnancy: From the first trimester to delivery

We report herein the longest-lasting study of SARS-CoV-2 antibody profile in pregnancy, from first trimester-infection to delivery. Seventeen out of 164 pregnant women tested positive for COVID-19. Throughout pregnancy, the neutralizing antibody titer remained stable, whilst a significant decline in the non-neutralizing antibodies was observed after 16 weeks of gestation. All the newborns of women who developed IgG antibodies showed the presence of the same antibodies in arterial cord blood. Knowledge on the longevity and type of SARS-CoV-2 antibody response may help to guide vaccination strategies in pregnancy.