Vaccination from the early second trimester onwards gives a robust SARS-CoV-2 antibody response throughout pregnancy and provides antibodies for the neonate

OBJECTIVES

Preventative measures against Coronavirus Disease 2019 (COVID-19) are essential for pregnant women; they are particularly vulnerable to emerging infectious pathogens due to alterations in their physiology. We aimed to determine the optimum timing of vaccination to protect pregnant women and their neonates from COVID-19.

METHODS

A prospective observational longitudinal cohort study in pregnant women who received COVID-19 vaccination. We collected blood samples to evaluate levels of anti-spike, receptor binding domain (RBD) and nucleocapsid antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) before vaccination, and 15 days after first and second vaccination. We determined neutralizing antibodies from mother-infant dyads in maternal and umbilical cord blood at birth. If available, IgA was measured in human milk.

RESULTS

We included 178 pregnant women. Median anti-spike IgG levels increased significantly from 1.8 to 5431 binding antibody units/milliliter (BAU/mL) and RBD from 6 to 4466 BAU/mL. Virus neutralization showed similar results between different weeks' gestations at vaccination (p > 0.3).

CONCLUSIONS

We advise vaccination in the early second trimester of pregnancy for the optimum balance between maternal antibody response and placental antibody transfer to the neonate.

Maternal stress in the postpartum period is associated with altered human milk fatty acid composition

BACKGROUND & AIMS

Maternal stress in the postpartum period affects not only the mother, but also her newborn child who is at increased risk for a wide range of disorders later in life. The mechanisms underlying transmission of maternal stress to the child remain elusive. Human milk (HM) is a potential candidate and is an important source of fatty acid (FA), which are crucial for child (neuro)development. This study aims to investigate whether maternal psychological and biological stress influences HM FA composition over the first month postpartum.

METHODS

The Amsterdam Mother's Milk study is a prospective cohort study. We included lactating women who delivered at term with a large range of stress levels: a high stress (HS) group, women whose child was hospitalized for a minimum of 2 days (n=23) and a control (CTL) group, women who gave birth to a healthy child (n=73). HM was collected three times a day at postpartum days 10, 17 and 24. Perceived psychological stress was measured using multiple validated questionnaires, while biological stress measures were based on cortisol in hair, saliva and HM. HM FAs were analyzed by gas-chromatography and compared between groups.

RESULTS

Maternal perceived stress scores were significantly higher in the HS group (p < 0.01), whereas cortisol measurements did not differ between groups. The absolute concentrations of total FA in HM (p=0.023), including the total amount of poly unsaturated fatty acids (PUFAs) (p=0.022) and omega-6 PUFAs (p=0.018), were lower in the HS group compared to the CTL group. Relative values of FAs did not differ between groups.

CONCLUSION

Maternal stress in the first month postpartum was associated with overall lower levels of FA in HM. This possibly indicates a route of transmission of maternal stress signals to the infant. Future research should investigate if these stress-induced changes in HM FAs have consequences for child development.