You may have heard how COVID-19 can affect pregnant women in the news, but maybe not how it can contribute to female infertility.

When someone is infected with COVID-19, their immune system mounts a aggressive response. This response has been called the 'cytokine storm' as the immune system's cytokines can over respond.

Cytokines are released by T helper cells (TH) and triggers the activation of the B cells. B cells secrete antibodies that attack antigens. In this case against COVID-19.

Th cell-mediated specific immune responses are made up of two forms: type 1 T helper (TH1) and type 2 T helper (TH2) cells. Both environmental and genetic factors act together to determine which one will be dominant, either TH1 or TH2. It is much like a seesaw, where the balance is often tipped in favour of one more than the other.

In terms of fertility, it’s the TH cells that affect implantation of the embryo into the uterus wall. If TH1 is dominant, the woman's body has more inflammation, which suppresses implantation. If TH2 is dominant, your body is less inflamed and the body allows the embryo to implant. Another way to look at it is to imagine your body as a castle, surrounded by a moat of water with a drawbridge, which is your immune system.

A woman's body is constantly on the defence against potential attackers from outside the castle. During most of your menstrual cycle, the castle is prepared for attack and the drawbridge is up – TH1 is dominant. However, for four to five days of the month after ovulation, the drawbridge is down and the woman's immune system is lowered and TH2 dominates, allowing implantation of the embryo into the uterus wall.

Research has shown that if cytokines CD8+ are too high, it can lead to an embryo not being able to implant into the uterus wall and can increase the risk of miscarriage. Researchers found in people with COVID-19, that their CD8+ cells are too high.

This contribution to infertility may only be short-lived as we either don't get the virus or become immune to it. In the short term, boosting your immune system with natural herbs just as ginseng can help your immune system and fertility. Otherwise, acupuncture has been shown to both regulate cytokines and the immune system.