COVID-19 and Pregnancy

SARS-CoV-2 (COVID-19) has been a unique experience for everyone, both here in Australian and overseas.  The impacts on society, health and mental well being are self-evident and no doubt will continue to be detailed for years to come.  Understandably, given the approach of mainstream and social media to this pandemic, many women and their partners have experienced fear and uncertainty around the potential impact of COVID-19 during pregnancy and advice surrounding vaccination in pregnancy.  Hopefully the information on this page will be helpful for those that have questions or concerns.

What do we know?

Recommended COVID-19 vaccines are safe in pregnancy and expert consensus is to encourage pregnant women, recently pregnant women and women planning pregnancy to ensure that they are up to date with their vaccination schedule.

The majority (75%) of women will have mild or asymptomatic disease.  Those women who develop symptoms, particularly if unvaccinated or if they have other medical concerns, are at a significantly greater risk of severe disease.

COVID-19 increases the risk of blood pressure disorders and stillbirth.  Severe disease may precipitate preterm delivery - usually elective for maternal concerns.  Newborn outcomes reflect preterm delivery more than COVID-19 infection.

COVID-19 Vaccines in pregnancy

None of the recommended COVID-19 vaccines contain replicating virus - therefore they do not cause disease. Review of epidemiological data is very reassuring and demonstrates no impact upon any of the following concerns:

  • fertility

  • embryo/foetal development

  • short term postnatal development of the newborn

  • pregnancy outcomes including childbirth

Benefits of vaccination include:

  • reduction in maternal COVID-19 infection

  • reduction in maternal severity of COVID-19 infection

  • reduction in perinatal death (ie. stillbirth or newborn loss)

  • reduction in infant hospitalisations up to 6 months of age - maternal antibodies, derived from being vaccinated, cross the placenta and provide passive immunity to the newborn

By way of example, a Scottish study (18,000 pregnancies) demonstrated the following:

  • 77% COVID-19 infections occurred in unvaccinated patients (out of a total of 4950 infections)

  • 91% of COVID-19 hospital admissions involved unvaccinated patients

  • 98% of critical care admissions and 100% of stillbirths occurred in unvaccinated patients.

[ref]​

Safety concerns with vaccines:

It is important to acknowledge that, as with any medication, adverse reactions can occur.  Common side effects are mild and include pain at the injection site and generalised malaise, fatigue, fevers, chills and the like - these reflect activation of the immune system.

Serious side effects are rare:

  • Pfizer - 

    • Anaphylaxis - 5/million doses​

    • Myocarditis/pericarditis (inflammation of the heart) - 2-11/million doses in women

  • Moderna - ​

    • Anaphylaxis - 2-3/million doses​

    • Myocarditis/pericarditis - 7-8/million doses

Timing of vaccination in pregnancy:

In essence, whenever the vaccine is due (primary, secondary or booster) is the time when administration of the vaccine should ideally occur.  It is important to understand that it takes a number of weeks for the body to respond to a vaccine, during which time benefit is lacking/reduced.  Consequently, maternal benefit is optimised the earlier in pregnancy that a vaccine is administered.

Additional considerations:

  • influenza and pertussis vaccines (routinely advised in all pregnancies) can be administered at the same time as COVID-19 vaccines;

  • Anti-D (advised for women with a Rhesus negative blood type) can be administered at the same time as COVID-19 vaccines.

Maternal impacts of COVID-19

Thankfully, for most women who contract COVID-19 in pregnancy the disease will be either mild or asymptomatic (as we see with the general non-pregnant population) particularly with the currently predominant Omicron variant - studies vary but at least 75% of COVID-19 infections will be mild/asymptomatic.  

For those who are symptomatic a variety of non-specific symptoms are commonly reported and include:

  • fever

  • respiratory symptoms - cough, runny nose, sore throat

  • loss of smell/taste

  • muscle aches and pains

  • headache

  • nausea/vomiting

  • chest pain

  • confusion

Overlap of these symptoms with a variety of other infections and medical conditions (eg. pre-eclampsia) is self evident and as such appropriate clinical assessment is critical before making a diagnosis of COVID-19.​

The issue with COVID-19 in pregnancy is that while pregnant women are not more likely to contract COVID-19, those that become symptomatic are at a greater risk of clinically significant disease progression including severe illness and death - roughly 4 x greater risk of death, predominantly if unvaccinated (9:1000 vs 2.5:1000 in one American study [ref]). 

Data is mixed in quality, however, studies consistently demonstrate an increase in severe complications for pregnant women who acquire COVID-19:

  • Pneumonia - 10% pregnant vs 6.5% non pregnant

  • ICU admission - 10.5% pregnant vs 4% non pregnant [ref]

Other complications associated with moderate to severe COVID-19 include:

  • Respiratory failure

  • Cardiac disorders

  • Blood clotting complications

  • Kidney damage

  • Seizures and neurological concerns

  • Intestinal and liver damage

  • Psychiatric consequences including PTSD

In all studies, risk is increased by maternal comorbidities such as hypertension, obesity and age over 35 years and the risk of such complications is reduced by vaccination.

Pregnancy and foetal complications of COVID-19

COVID-19 is associated with placental dysfunction - this appears to be more significant with the Delta variant as compared to the Omicron variant.  The question of "vertical" transmission - ie. infection of the unborn foetus - remains one of ongoing interest and is thought to be less than 2% with most newborn infections thought to have arisen from postnatal contact with either an infected mother or relative.

Specific pregnancy related risks include:

  • Preterm delivery - marginal increase most likely in the setting of severe maternal disease

  • Pre-eclampsia and severe pre-eclampsia/HELLP Syndrome

    • Increased in all COVID-19 patients - ie mild or severe illness though greater in severe illness​

    • Mild to moderate COVID-19 - roughly 60% increased risk

    • Moderate to severe COVID-19 - greater than 100% increased risk

  • Stillbirth - increased risk of stillbirth in pregnancies affected by COVID-19 (1.25% vs 0.6%)​

    • Stillbirth rates appear to be higher still with the Delta variant and in women with comorbidities or severe complications of COVID-19​

Newborn outcomes appears to predominantly be reflective of complications arising from preterm delivery with the vast majority of COVID-19 positive neonates having mild disease (>95%).  Newborn death rates do not appear to be increased.

COVID-19 has created a lot of stress and anxiety for pregnant women and there are a number of unfounded concerns relating to vaccination in pregnancy.  If you have any questions about COVID-19 vaccination and pregnancy you should discuss these with your obstetrician or general practitioner who will most certainly endeavour to reassure you and encourage that you either get vaccinated or maintain your vaccinated status in pregnancy.  The wealth of scientific literature has consistently demonstrated that the recommended COVID-19 vaccinations are safe, effective and significantly reduce the risk of severe maternal disease, death and poor newborn outcomes.