Dr Danie Schneider
Obstetrician and Gynaecologist, Somerset West

Covid vaccine in pregnancy

Is vaccinating pregnant women new?

It has been common practice for some time to offer pregnant women and women who are breastfeeding vaccines. Women are therefore routinely and safely offered vaccines in pregnancy against e.g. influenza and whooping cough. It is important to note that many of the vaccines also protect your baby against infection.  These vaccines, like the Covid-19 vaccines, are non-‘live’ vaccines, which are generally considered safe in pregnancy. Please see separate entry labelled “Immunisations in pregnancy “.


Why vaccinate pregnant women against Covid?

Although more than half of pregnant women who test positive for Covid in pregnancy have no symptoms at all, we now know that some pregnant women can get life-threatening illness from Covid-19. Severe disease is more common if you have an underlying illness (co-morbidity).

We also know that pregnant women are at an increased risk of becoming seriously ill from Covid in the later stages of pregnancy. If this does happen, pregnant women are more likely to have a premature baby.

The main benefit of vaccination would therefore include a reduction in severe disease for pregnant women. This would also decrease the risk of having a premature baby as well as potentially reducing the risk of spreading the virus to vulnerable household members.


Tell me more about the covid vaccine  available in South Africa

Unlike the other covid-19 vaccines currently available that use new technology involving messenger RNA ( eg Pfizer-BioNTech and Moderna mRNA ), the Johnson& Johnson vaccine utilises a method that has been widely used for years. The J&J vaccine uses a disabled adenovirus (similar to viruses that cause the common cold) to deliver instructions to the body’s cells to briefly make copies of the Covid virus spike protein. The recipient’s immune system then makes protective antibodies against the virus spike protein. It is important to know that the coronavirus needs its spike protein to be able to infect the body’s cells and antibodies against the spike protein can therefore block Covid infection before it starts.

The J&J COVID-19 Vaccine includes the following ingredients: recombinant, replication-incompetent adenovirus type 26 expressing the SARS-CoV-2 spike protein, citric acid monohydrate, trisodium citrate dihydrate, ethanol, 2-hydroxypropyl-β-cyclodextrin (HBCD), polysorbate-80, and sodium chloride.

J&J’s vaccine could be a potential game changer, at least in Africa. This single-dose vaccine does not need to be frozen when it is shipped and distributed. It can thus be stored at the temperature of a regular refrigerator.


How is the J&J vaccine roll out done in SA and what are the implications for pregnant women?

It is important to understand that the vaccine is not a registered product. There is as yet no approved vaccine to prevent Covid-19 and emergency use has been authorised in many countries.

Research data from the phase 3 ENSEMBLE clinical trial showed that the single-shot J&J vaccine offered strong protection against severe disease and hospitalisation in South Africa. This trial involved over 40 000 participants, and was tested in SA where the new, highly infectious variant, 501Y.V2, had been dominating infections during the second wave.

It is currently being deployed in the country as part of a phase 3B implementation study which was designed together with the South African Health Products Regulatory Authority (Sahpra).

A phase 3B study is where scientists already know the vaccine is efficacious and they don’t have to do a randomised study with a placebo. This means the vaccine can be studied in a real-life situation to see how well it works. Other studies are also being done and a phase 2A study will assess the vaccine in adolescents and pregnant individuals.

Note that the J&J   vaccine has not yet been tested in pregnant women and at present pregnant women are excluded from the SA study. It is however expected that pregnant women will be included in the study in the near future and that this would probably apply to women after the first trimester or 18 weeks.


What are potential risks for the mother? 

Remember that the J&J vaccine does not contain SARS-CoV-2 and cannot give you covid-19.

The vaccine has not been tested in pregnant women as they were excluded in the recent vaccine trails. There is however multiple research studies on the way and safety data will become available in the coming months.

The experience from non-pregnant people is that post-vaccination symptoms are typically mild to moderate in severity and occur in the first 3 days after vaccination. Pain, tenderness and redness at the injection site, headache, chills, joint pain, muscle pain, tiredness, generally not feeling well, nausea and fever have been seen with this vaccine. Most symptoms resolve within 1-2 days and respond to paracetamol.

It is very rare for anyone to have a serious allergic reaction to a vaccine. If this does happen, it usually happens within minutes. The person who vaccinates you will be trained to deal with allergic reactions and treat them immediately. With fast treatment you will make a good recovery. 

It is important to understand that vaccines that containing the adenovirus (Ad26-based vaccines) have been given to participants in numerous studies to prevent e.g. Ebola virus, Zika virus, RSV, HPV and malaria. This includes more than 99 000 participants in an ongoing Ebola vaccine study in the DRC. The Ad26-based vaccines have also been studied in test tubes and in animals and no vaccine related adverse effects observed.


What is potential risk for the baby?

The Covid-19 vaccines do not contain ingredients that are known to be harmful to pregnant women or to their developing babies. The vaccines are not “live” vaccines so cannot cause or transmit Covid -19 to your baby. Similar “non-live” vaccines have been used for years to protect against flu and whooping cough in pregnancy. It is important to understand that similar existing adenovirus vaccines include one for Ebola that has been safely administered to babies as young as 1 year old, and another for respiratory syncytial virus that was safely given to newborns. Nearly 200,000 people have received adenovirus vaccines, with no serious safety issues.


Are there other potential benefits of Covid vaccination in pregnancy?

In a recent study, maternal antibodies to Covid-19 were found to have crossed the placenta after infection of the mother in pregnancy. These important findings demonstrate the potential for maternal antibodies to transfer to the fetus and provide neonatal protection. Further research will show whether these antibodies are protective against newborn infection and whether a vaccine can produce a similar response.


How is the use of Covid vaccines in pregnancy monitored in the interim while we wait for more data?

Studies are in process worldwide and both Pfizer and J&J are including pregnant women.

The FDA in the USA recently did a detailed assessment of the data pertaining to the J&J vaccine before allowing emergency registration. To date there  have been 154 adverse events reported by pregnant people in the Vaccine Adverse Event Reporting System, which is operated by the CDC and the FDA. About half of those people report having been vaccinated in the first 13 weeks of their pregnancies. Reassuringly most of the adverse events reported were not related to pregnancy e.g. headache, fatigue, chills and reactions at the injection site. There were 29 spontaneous abortions or miscarriages reported, but one must remember that we have known for years that about 10% to 20% of all pregnancies end through spontaneous abortions or miscarriages. The miscarriage number therefore is not concerning given the expected background rate. The CDC is also maintaining a registry of people who report they were pregnant following vaccination. They are being followed, with check-ins every three months and up to three months after the birth of the baby. There are 1,815 people in the pregnancy registry so far.

To date, over 30,000 pregnant women have self-reported within the CDC v-safe program, which collects and reports outcomes including miscarriage and stillbirth, pregnancy complications, maternal ICU admission, adverse birth complications, neonatal death, infant hospitalisations and birth defects . No concerning pregnancy related complications have so far been observed following Covid vaccination in pregnancy.


Does the Covid vaccine affect fertility?

There is no evidence to suggest that Covid-19 vaccines will affect fertility. No evidence to date has been presented that show that women that have been vaccinated have had fertility problems. We know that most people who contract Covid will develop antibodies to the spike protein and there is no evidence of fertility problems in those people who have already had Covid.

There is no biological plausible mechanism by which the vaccines could impact fertility, but more evidence will become available over time.


Does it matter at what stage of pregnancy I am and whether I am breastfeeding?

The vaccine is safe to use in women who are breastfeeding, both for mother and baby.

The vaccine should also work whatever the stage of your pregnancy. The biggest decision however is balancing the risk-benefit ratio for your individual situation.


How do I then decide if and when I get the vaccine?

When the vaccine is available to pregnant women in SA, we will discuss your individual risk in consultation. We will balance the available data on vaccine safety with your individual risk for Covid acquisition, as well as your individual risk for moderate or severe Covid disease in pregnancy. The level of Covid community transmission will also be considered before decision making. Remember that Covid has more serious complications in later pregnancy and that on the other hand most of the baby’s development takes place early on in the pregnancy. We will therefore discuss the timing of your vaccine in detail.

If you are in one of the groups offered the vaccine, getting vaccinated before pregnancy will help prevent Covid-19 infection and its serious consequences. Some women will need to make a decision about whether to delay pregnancy until after the vaccine becomes available to them. We can discuss this in consultation and work out a specific plan for you.


Should I get the vaccine if I have had Covid before?

Vaccination should be offered regardless of previous symptomatic or asymptomatic Covid.  We therefore do not advise viral or serologic (antibody) testing  for the purpose of vaccine decision making. 


What do we know about life after the Covid vaccine?

It is important to remember that these vaccines are about a year old, so we are still researching the impact of vaccination on individuals, as well as communities. Early indications are that the vaccines are durable, but we will only know over time how long the immunity lasts and whether a booster shot is needed.

It is important to understand that none of the research has so far looked at transmission of the virus after vaccination. The focus has been on protection of the individual and new studies need to be designed to look at transmission. For this reason it is recommended that vaccinated persons continue to follow all current guidance to protect themselves and others from infection, including wearing a mask, hand washing and social distancing, and adhere to quarantine guidance after exposure to COVID-19.