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There is no definitive evidence that demonstrates that the COVID modRNA transfections reduce fertility, but there is a growing body of circumstantial evidence from observational research that shows that taking multiple modRNA doses is associated with a decline in successful conception rates, higher rates of fetal loss, changes in the menstrual cycle and depletion of ovarian reserves.

Lower rates of successful conception

A population-based retrospective cohort study conducted in the Czech Republic for the period between January 2021 and December 2023 that included birth and vaccination data on all birth age adult women (18-39 years of age) in the Czech Republic (n = 1.3 million) found that from June 2021 onward, successful conception rates per 1,000 women were considerably lower for vaxxed women compared to unvaccinated women prior to conception. Vaxxed women had a 33% lower successful conception rate compared to unvaxxed women. The successful conception rate among vaxxed women was also lower than expected based on their proportion in the population. The successful conception rate also had a dose dependent response as women with 3 or more doses had the lowest conception rate (78.2 per 1,000) compared to those with 1–2 doses (85.6 per 1,000) and unvaxxed women (122.7 per 1,000).

Higher than expected fetal loss following modRNA transfection

An observed to expected fetal loss regression analysis of singleton pregnancies in Israel between 2016 and 2022 among women vaxxed for flu, prior to COVID, or COVID-19 between 8-27 weeks gestation (n = 226,395) found, using an individual-level baseline reference model with last menstruation period data from 2016-19, that pregnant women vaxxed between 8-13 weeks gestation had a higher than expected frequency of fetal loss compared to the baseline model. The frequency of observed fetal losses for women who received at least one Pfizer modRNA dose was nearly 4 per 100 pregnancies above the expected frequency of fetal losses (9 per 100 pregnancies) compared to women vaxxed prior to pregnancy for flu or COVID-19. 3 of the 4 additional fetal losses occurred after 14 weeks gestation. The earlier flu vaxx cohort (2016-19) had a lower than expected frequency of fetal losses during the same gestation period with 5 fewer fetal losses per 100 pregnancies compared to the control cohort vaxxed prior to pregnancy. The baseline reference model included covariates for female age, health status, health seeking behavior and SES.

modRNA effect on Ovarian Reserves

A randomized rodent experiment conducted on female wistar rats given either a saline placebo, COVID modRNA transfection, or inactivated coronavirus, found, after euthanizing the subjects and collecting ovarian tissue that COVID-19 vaccines, particularly the mRNA vaccine, ‘may exert toxic effects on ovarian follicles and ovarian reserve in rats’ as both platforms were found to cause elevated transforming growth factor-beta cytokine levels in ovarian tissue associated with fibrotic scarring. The authors suggest that the modRNA transfection in particular may increase depletion of ovarian follicles by increasing recruitment and programmed cell death, reducing ovarian reserve.

Pregnancy risks

A retrospective, population-based cohort study that queried the VAERS database between 1990 and 2024 for 37 different pregnancy complications, including 27 before birth and 10 after birth, found that compared to all other immunizations, those associated with COVID-19 had a proportional reporting ratio greater than 2 across all 37 adverse events with a mean proportional reporting ratio of 69.3.

Irregular Menstrual Cycles

A global epidemiological survey (n =10,000), published in the Journal of the Endocrine Society, found that ‘reproductive AEs (adverse events) in vaccinated individuals without COVID-19 illness were more frequent than in unvaccinated individuals with COVID-19 illness.’ 7.5% of unvaxxed women reported irregular menstrual cycles following SARS-Coronavirus infection compared to 17% women who reported irregular and heavier periods (menstrual bleeding) after receiving the vaxx.

A cross-sectional survey-based study conducted in Saudi Arabia in October 2022 (n = 1503), published in the International Journal of Health Sciences, found that 37% of participants were infected after being vaxxed and 82% reported side effects. 21% of recipients reported persistent side effects: 1 in 23 female recipients developed menstrual disorders, 1 in 44 recipients suffered hair loss, 1 in 29 recipients suffered chronic fatigue, 1 in 34 recipients suffered joint pain, 1 in 88 recipients suffered heart palpitations and 1 in 79 recipients developed memory loss problems. Even worse, about 1 out of 8 recipients (12.64%) reported being diagnosed with a disease shortly after being vaxxed with most being diagnosed after the second dose or booster shot. The most common were the flu, common cold, and thyroid gland disorder.

Higher rate of abnormally low platelet counts among vaxxed pregnant women

A case control study conducted among pregnant women at a Department of Gynaecology and Obstetrics of a Pakistani hospital (n = 189) found that vaxxed women were more likely to develop thrombocytopenia (39.5%) during the 6 month duration of the study than unvaxxed pregnant women (28. 1%), especially among women over the age of 35 years and those with pre-existing hypertensive disorders.