The evidence so far suggests that mRNA vaccines are safe for pregnant and breast-feeding women
Bangladesh is currently facing a surge in Covid-19 infections, predominantly owing to the Delta variant, which is causing considerable morbidity and mortality. There are also increasing reports of adverse outcomes and fatalities from Covid-19 among pregnant women in the country in recent times, with the situation likely far worse in rural areas, where poor surveillance, delayed testing, and a general lack of access to critical care is prevalent.
Accelerated nationwide vaccination of the population is crucial to curbing this surge. While a certain degree of vaccine inertia and vaccine hesitancy might still remain among the general population, there is a need to disseminate updated information on the safety of Covid-19 mRNA vaccines in pregnant and breast-feeding women, in view of offering pregnant women the opportunity to be immunized against the virus.
This is crucial because although the overall risk of severe illness is low, symptomatic pregnant women who contract Covid-19 are at greater risk of more severe illness requiring admissions in intensive care units (ICU), complications such as the need to be ventilated and death from the disease, in comparison to those who are not pregnant. They may also be at increased risk of pre-term birth and other adverse pregnancy outcomes. Pregnant women with Covid-19 who have other co-morbid medical conditions (such a gestational diabetes or a high BMI indicating overweightness) are at even greater risk. Furthermore, pregnant women also interact heavily with health care services throughout the three trimesters, often needing to visit high risk places like laboratories and hospitals for follow-up and investigations.
Large phase III randomized controlled trials that tested the safety and efficacy of the Covid-19 vaccines did not include pregnant women as participants. This is not peculiar to Covid research; indeed, pregnant women are excluded from trials owing to their status as a “scientifically complex” population whose inclusion in research must be done with consideration of the unique state of pregnancy. As a result, there is limited data on the safety of Covid-19 vaccines among pregnant women, and indeed no randomized evidence to support it.
However, preliminary observational real-world data emerging from countries with higher proportions of vaccinated populations have found no safety concerns for the mRNA vaccines against SARS-Cov-2 among pregnant women. The preference for mRNA vaccines in pregnant women is based on the fact these are not live vaccines, and as such cannot replicate, and therefore cannot cause infection in either the woman or the unborn child. Moreover, other such non-live vaccines have previously been shown to be safe in pregnancy (for example, flu and whooping cough).
Over 120,000 pregnant women from diverse ethnic backgrounds in the US have received either a Pfizer-BioNTech or Moderna Covid-19 vaccine, with no evidence of harm being identified. More recent retrospective data from Israel found a significantly lower risk of SARS-CoV-2 infection among pregnant women who had received the Pfizer mRNA vaccine, compared with those who were not vaccinated. There is also data to indicate the ability of Covid-19 mRNA vaccines to mount an immune response against the virus, thus indicating efficacy, with vaccine-elicited antibodies being transported to infant cord blood and breast milk.
Although these studies were limited by their observational design, on the background of encouraging data on the safety of mRNA vaccines, the US’s FDA authorized the use of mRNA vaccines in pregnant and breast-feeding women, should they wish to take it. This was supported by the American College of Obstetricians and Gynecologists (ACOG) and the Society for Maternal-Fetal Medicine (SMFM). The WHO recommends the use of Covid-19 vaccines in pregnant women when the benefits of vaccination outweigh the potential risks, with an informed decision being made in the local epidemiological context. The International Federation of Gynecology and Obstetrics (FIGO) supports a similar notion.
Further, latest advice from the Joint Committee on Vaccination and Immunization (JCVI) in the UK concur that Covid-19 vaccines should be offered to pregnant women.
Within the South Asian region, the Indian government’s advisory group for vaccines has allowed pregnant women to get immunized against Covid-19, with an operational guideline for vaccinating pregnant women being mandated in July. Previously, in May, the Indian government greenlighted the Covid-19 vaccine for women who were breast-feeding as well.
Despite the high risk of infection and critical Covid-19 illness caused by the more transmissible Delta variant, pregnant women are not currently eligible for vaccination registration in Bangladesh. On the background of data on its safety in pregnant women in other parts of the world, women who are pregnant or who intend to, should be offered the choice of getting themselves vaccinated.
Considering these issues, the decision to open up the vaccines to pregnant women needs to be addressed urgently. While getting vaccinated is indeed a personal choice, the decision should be informed by a discussion with the respective physician. Further, current level of activity of the pandemic, and trends in Covid causalities in the locality/community should be important considerations guiding this choice to get vaccinated, especially given the virulent nature of the Delta variant and data on more severe Covid among pregnant women.
Aaysha Cader, MD, MRCP (twitter: @aayshacader), is a cardiologist with an interest in clinical trials research at the Ibrahim Cardiac Hospital & Research Institute, Dhaka. Reshma Sharmin, MRCOG, FCPS, is an obstetrician and gynaecologist at Chittagong Medical College and Hospital, Chittagong.