Moderna and Pfizer Covid vaccines found safe and effective for pregnant women by study

Coronavirus vaccines made by Pfizer and Moderna are safe for pregnant women and breastfeeding moms, trigger a strong immune response and antibodies from the shots even pass to their babies, a new study finds.  

Pregnant or lactating women, who get vaccinated against Covid-19 produce antibodies, which are passed on to the baby through breast milk and the placenta, say scientists.

Tens of thousands of pregnant American women have already opted to get vaccinated against COVID-19, with ‘no red flags’ Dr Anthony Fauci said last month – but expecting mothers are typically excluded from trials of shots, so exactly how safe or effective the vaccines were for them was unknown. 

U.S. doctors advised that pregnant women should be warned that the risks were not entirely known but should not be discouraged to get vaccinated. 

With the findings of the new Massachusetts General Hospital study, pregnant women can breathe a sigh of relief and sign up to get vaccinated in most states, since pregnancy is condition that puts women at high risk from COVID-19. 

Expectant mothers are more likely to develop severe Covid symptoms, requiring hospitalization, intensive care and ventilation.

There have also been concerns the sometimes deadly virus could negatively impact the baby’s birth.

But because pregnant women have been left out of clinical trials, how the Covid vaccines impact their immune system has remained uncertain, the researchers say.

‘This news of excellent vaccine efficacy is very encouraging for pregnant and breastfeeding women, who were left out of the initial COVID-19 vaccine trials,’ said study author Dr Andrea Edlow at Massachusetts General Hospital. 

‘Filling in the information gaps with real data is key, especially for our pregnant patients, who are at greater risk for complications from COVID-19.

‘This study also highlights how eager pregnant and lactating individuals are to participate in research.’

The researchers looked at women who had received one of the two new mRNA vaccines – Pfizer or Moderna.

Out of the 131 women involved in the study, 84 were pregnant, 31 were lactating and 16 were not pregnant.

Antibody levels among all three groups of women were the same, the researchers found.

They were also found in all umbilical cord blood and breast milk samples taken from the participants.

‘We now have clear evidence the COVID vaccines can induce immunity that will protect infants,’ said study co-author Dr Galit Alter.

‘We hope this study will catalyse vaccine developers to recognise the importance of studying pregnant and lactating individuals, and include them in trials.’

Side effects after vaccination were rare and comparable across all three study groups, the researchers also found. 

‘The potential for rational vaccine design to drive improved outcomes for mothers and infants is limitless, but developers must realise that pregnancy is a distinct immunological state, where two lives can be saved simultaneously with a powerful vaccine,’ said Dr Alter. 

‘We look forward to studying all vaccine platforms in pregnancy as they become available.’

Both vaccines produced ‘significantly more’ mucosal antibodies (IgA) than the body’s natural response to COVID-19.

Antibody levels measured after the second jab were highest among participants who had received the Moderna vaccine, the researchers also found.

‘This finding is important for all individuals, since SARS-CoV-2 is acquired through mucosal surfaces like the nose, mouth and eyes,’ said Dr Kathryn Gray, another of the study’s co-authors.

‘But it also holds special importance for pregnant and lactating women because IgA is a key antibody present in breastmilk.’

The findings were published in the American Journal of Obstetrics and Gynaecology (AJOG).