The information bellow is based on the opinion of the Czech Society of Vaccinology of the Czech Medical Society of Jan Evangelista Purkyně and the Czech Gynecological and Obstetrical Society.
Vaccination and fertility
There is absolutely no evidence and no theoretical reason that any of the Covid-19 vaccines could affect female or male fertility. Vaccination does not cause infertility. At the same time, vaccination cannot affect the treatment of infertility. However, it is recommended to evaluate the timing of vaccination during infertility treatment and to delay the administration of the vaccine for a few days in case of some treatments, such as in case of oocytes retrieval during in vitro fertilization, due to the possibility of post-vaccination adverse reactions which could not be distinguished from the response to the treatment.
Vaccination and pregnancy
Pregnant women are not at greater risk of contracting Covid-19 compared to women in the same age group, but may have a more severe course of the disease. Most pregnant women are asymptomatic or have a mild course of Covid-19. Pregnant women in the third trimester of pregnancy have a higher risk of severe Covid-19 disease. Other risk factors for a severe course of Covid-19 in pregnancy are: age over 35 years, obesity, pre-existing diabetes mellitus, pre-existing hypertension and other chronic diseases. Pregnant women with Covid-19 disease in the third trimester of pregnancy have a higher risk of preterm delivery when compared to pregnant women without Covid-19.
Vaccination in pregnancy should be planned after the 12th week of pregnancy, i.e. any time from the 13th week of pregnancy. The first 12 weeks of pregnancy are the most important for the development of the baby. If pregnancy is detected after the first dose of covid-19 vaccine, it is advisable to administer the second dose after the 12th week of pregnancy has been completed. The vaccine is functional and stimulates the immune system regardless of the stage of pregnancy at which it is given. Vaccination can also be given immediately after delivery.
For women planning a pregnancy, there is no need to delay conception after vaccination.
The decision to receive a vaccination against Covid-19 in pregnancy is a personal and individual choice of the pregnant woman. Vaccination against Covid-19 in pregnancy is particularly appropriate for women at higher risk of infection and for women at increased risk of severe Covid-19 disease.
However, the large clinical trials that have shown that Covid-19 vaccines are safe and effective have not included pregnant women. This means that at this time only limited information is available on the effects of Covid-19 vaccination in pregnant women.
Also, until now, a relatively small number of women have become pregnant after receiving the vaccine. So far, there have been no signs of complications from vaccination in pregnant women, but the numbers vaccinated are still too small to draw definitive conclusions. Monitoring results in the United States, where more than 100,000 pregnant women have received the Covid-19 vaccine, have not raised any safety concerns. Similarly, no warning signs have yet been reported from Israel, where vaccination of pregnant women is recommended and implemented. Covid-19 vaccines do not contain ingredients known to be harmful to pregnant women or the developing fetus.
Vaccine manufacturers continue to collect data and review data on women who have received the vaccine and become pregnant. No warning signs have yet been recorded.
Vaccination and breastfeeding women
Based on the mechanism of action of Covid-19 vaccines in the human body, these vaccines are not considered risky for a breastfeeding woman and her breastfed baby. Therefore, breastfeeding women can also be vaccinated against Covid-19.
However, there have not yet been sufficient clinical trials on Covid-19 vaccination in breastfeeding women. Therefore, there are no data available on the safety of Covid-19 vaccines in breastfeeding women, the effect of Covid-19 vaccines on the breastfed infant and the effect of Covid-19 vaccines on milk production or excretion. The first available studies demonstrate the possibility of antibodies being transferred into the breast milk after vaccination. Thus, vaccination of pregnant and breastfeeding women could provide protection not only for the mother but also for the developing or breastfed infant.
A study assessing the safety of vaccines from Pfizer/BioNTech and Moderna in more than 35,000 pregnant women in the US found no increased risks to pregnancy, delivery or the newborn.
In accordance with the recommendation of the Czech Society of Vaccinology of the Czech Medical Society of Jan Evangelista Purkyně and the State Institute for Drug Control of 20.5.2021 for the prevention of the very rare adverse effect of thrombosis with thrombocytopenia syndrome (TTS) in persons under 60 years of age, we do not recommend the use of Vaxzevria and Janssen vaccines in pregnant and breastfeeding women.
