There are no known fertility impacts from the COVID vaccine. It’s worth noting that in both the Pfizer and Moderna trials, which checked for pregnancy often and required all women to be on birth control, about as many women became pregnant in the vaccine sides of the trials than the placebo sides. In the Pfizer study, 12 women became pregnant in the vaccine group and had no known adverse effects in their pregnancies. Eleven women became pregnant in the placebo group and two miscarried of that group (which is about a normal miscarriage rate).
In the Moderna study, six women in the vaccine group and seven in the placebo group became pregnant. In the vaccine group, there were no reported problems in the pregnancies. Of the seven in the placebo group, one had an abortion and one miscarried.
The CDC notes that ‘No safety concerns were demonstrated in rats that received Moderna COVID-19 vaccine prior to or during gestation in terms of female reproduction, fetal/embryonal development, or postnatal development,’ and ‘There is no recommendation for routine pregnancy testing before receipt of a COVID-19 vaccine. Those who are trying to become pregnant do not need to avoid pregnancy after mRNA COVID-19 vaccination.’