InviMed specialists keep up to date with the situation, announcements from scientific societies and experts in the field of reproductive medicine. One of them is Professor Carlos Simon, obstetrician-gynaecologist and world-renowned expert in reproductive medicine. Below is his position on COVID-19 in the context of trying for a baby and pregnancy, presented during a webinar organised by the Igenomix Foundation.

Unknown risks

We are dealing with a new virus whose impact on our work in the field of assisted reproduction we do not yet know. Therefore, the first and foremost suggestion from the authorities dealing with this on a daily basis is to close the infertility clinics for the duration of the pandemic, because we have not yet sufficiently understood the impact of the virus on the fertilisation process and the early period of pregnancy. We cannot therefore expose our patients to unknown risks.

What should we know about SARS-CoV-2 coronavirus?

SARS-CoV-2 virus is characterised by its high infectivity. It shows a wide spectrum of symptoms in infected individuals, ranging from virtually none to fatal descent. As a pneumotropic virus, it causes severe respiratory distress syndrome.

Coronaviruses show tropism to epithelial cells lining the respiratory and gastrointestinal systems. The receptor for the virus is the protein ACE2, angiotensin converting enzyme II. This is a protein that regulates, among other things, blood pressure. In the reproductive system, the ACE2 protein is detected in the ovaries and gonadotropins induce changes in its expression. ACE2 is assumed to be involved in ovarian physiology. The protein has also been detected in the uterus, in endometrial epithelial cells during the secretory phase. In men, the ACE2 protein is found in Leydig cells (these are cells found in the male gonads, with nutritional and androgen-producing functions).

What impact can coronavirus infection have on pregnancy?

Previous studies on the impact of coronaviruses on pregnancy have been carried out in previous outbreaks of the coronavirus-causing diseases SARS and MERS.

In the case of SARS, the presence of viral particles was not found in the human reproductive system.

SARS infection in the first trimester of pregnancy did not cause fetal distress.
Infection in the 2-3rd trimester caused various disorders in pregnant women and fetuses. However, it was attributed to the effect of the virus on the patients' respiratory system. More hospital admissions and higher mortality rates were recorded.
In infected patients, an accelerated termination of pregnancy was carried out as an elective measure, due to the welfare of mother and child. Premature termination of pregnancy often resulted in perinatal complications in the children.
However, no maternal-to-fetal transmission of the virus was observed; the PCR test was negative in all newborns tested.

Similar results were observed for MERS infection. Also, transmission from mother to foetus was not demonstrated, nor did it occur during delivery. In the cases studied, good recovery of pregnant women and newborns was observed, which was influenced by the generally young age of the patients and infection in later pregnancy.

Why can coronavirus infection result in miscarriage?

The cause of miscarriages in cases of SARS coronavirus infection was maternal respiratory failure, as well as the use of the antiviral drug ribavirin, which should not be used in pregnancy. Fetal distress was associated with severe respiratory disease in the mother. This resulted in reduced oxygen supply to the fetus. Fetal development was also affected by the mother's general condition - severely weakened as a result of the virus infection.

COVID-19 and pregnancy

The COVID-19 pandemic has been ongoing for several months. Based on data up to the end of March 2020, we know that pregnant patients were infected in the 2nd to 3rd trimester of pregnancy. By the end of March, 44 babies were born, 12 pregnancies were terminated by caesarean section and 15 babies were born prematurely. Of this number, one baby died from multiple organ disorders. All other babies were in good health. In no case was virus transmission from mother to foetus observed.

However, it should be emphasised that there are very few reported cases and some of them may have been reported twice in the literature. There is also a lack of evidence obtained on an animal model.

Should efforts to have a baby be put on hold?

Given the lack of sufficient information on the impact of the virus on human fertility and early pregnancy, extreme caution is advised. Women wishing to become pregnant should postpone this decision until after the pandemic. This also applies to the activities of infertility treatment centres, which should suspend procedures so as not to expose patients to unnecessary risks.

The most important thing is life.

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Professor Carlos Simon

Obstetrician-gynaecologist, scientific director of Igenomix, a company providing advanced reproductive genetics services. Professor at the School of Medicine of the University of Valencia and at the Department of Obstetrics and Gynaecology at Stanford University in the United States.

The article from Prof Simon's webinar was prepared by Marta Wojciechowska, PhD, ESHRE Senior Embryologist, head of the embryology laboratory at the InviMed clinic in Gdynia.