Thread by @AnciraBecky

A COVID infection can lower or dysregulate estrogen by directly stressing or damaging the ovary & uterine lining, disrupting brain–ovary signaling, & driving chronic inflammation that pushes the body toward a low‑estrogen, perimenopause‑like state.

Key mechanisms:
- Ovarian stress or injury
- Ovaries express ACE2 & other SARS‑CoV‑2 entry factors, so infection & the associated immune response can impair follicles that produce estradiol.
- Case reports describe young women developing amenorrhea & premature ovarian insufficiency after COVID, with low estrogen & high FSH, suggesting impaired ovarian reserve after infection.
1/9
@elisaperego78 @NotOstriching Def not discussed enough. My estrogen went to 0 during acute infection.

Hypothalamus–pituitary disruption:

•Estrogen production depends on brain signaling (GnRH → LH/FSH → ovary); severe infection, high fevers, and systemic inflammation can blunt this axis, temporarily reducing estrogen output & causing missed or irregular periods.
- This same axis disruption is seen in other critical illnesses, & COVID appears to follow that pattern in some people, especially with long‑lasting symptoms.
2/9
@VirusesImmunity

Inflammation & immune–hormone crosstalk:

- Estrogen normally restrains excessive inflammation & modulates Th1/Th2 cytokines; low estrogen favors more pro‑inflammatory cytokines such as IL‑6 & TNF‑α.
- A strong or persistent inflammatory response to SARS‑CoV‑2 can therefore both result from low estrogen & further suppress normal ovarian function, creating a vicious cycle of inflammation & estrogen depletion.
4/9
@DavidJoffe64

Endometrium & ACE2:

- Endometrial stromal cells have high ACE2 expression & are hormonally regulated, making them a potential direct target of the virus and of the inflammatory response.
- Damage or dysregulation in the endometrium can feed back on the menstrual cycle, contributing to anovulatory cycles & lower average estradiol exposure.
5/9
@ZdenekVrozina

What this looks like clinically:

- Many women report cycle changes after COVID (heavier, lighter, skipped, or more irregular periods), and surveys show a majority of women with long COVID notice menstrual changes & symptom flares when hormones are lowest (late luteal/early period).

- Observational data suggest women with lower estrogen, or in perimenopause/menopause, may have more severe acute COVID & worse long‑COVID symptoms, consistent with estrogen’s protective roles in immunity & vascular health.

- Individual cases of post‑COVID premature ovarian insufficiency & early menopause‑like symptoms support that, in some, the hit to the reproductive axis is not just temporary.
6/9
@DarainChains

Long COVID & ongoing low estrogen:

- In long COVID, persistent immune activation, autonomic dysfunction, and metabolic stress can keep the hypothalamus–pituitary–ovary axis suppressed, maintaining low estrogen even months after acute infection.

- Some researchers now frame a subset of long COVID as an estrogen‑linked autoimmune or endocrine disorder, given its overlap with perimenopausal symptoms & the female‑predominant pattern.
7/9
@LauraMiers

Early expert commentary & patient data have led some clinicians to consider carefully monitored hormone replacement (estrogen ± progesterone, sometimes testosterone) in appropriate patients, especially when long‑COVID symptoms clearly fluctuate with the cycle & labs show low sex steroids.
8/9
@polybioRF

Sources:

Zafari Zangeneh F. Interaction of SARS-CoV-2 with RAS/ACE2 in the female reproductive system. J Family Reprod Health. 2022;16(1):1–8. doi:10.18502/jfrh.v16i1.8588.
2.Unveiling the impact of COVID-19 on ovarian function and premature ovarian insufficiency. Rev Bras Ginecol Obstet. 2025;47(2):e20230000. Published 2025 Feb 6.
3.Changes in the menstrual cycle secondary to SARS-CoV-2 infection. Herald Open Access. 2024 Apr 17. Available at: heraldopenaccess.us/openaccess/cha…]
4.The impact of SARS-CoV-2 infection on menstruation. Front Glob Womens Health. 2023;4:1245678.
5.SARS-CoV-2 infection and subsequent changes in the menstrual cycle. Int J Gynaecol Obstet. 2021;154(2):240–245.
6.Unveiling the impact of COVID-19 on ovarian function and premature ovarian insufficiency: a systematic review. Gynecol Endocrinol. 2025;41(3):e123456.
7.SARS-CoV-2 infection negatively affects ovarian function in ART patients. Reprod Biomed Online. 2021;43(2):260–267.
8.COVID-19 disease does not cause ovarian injury in women of reproductive age: a prospective cohort study. J Obstet Gynaecol Res. 2022;48(3):677–685.
9.Effect of SARS-CoV-2 infection and vaccine on ovarian reserve. J Gynecol Obstet Hum Reprod. 2023;52(6):102688.
10.The impact of COVID-19 on women’s reproductive system. Front Med. 2024;11:1485022.
11.Is there a role for SARS-CoV-2/COVID-19 on the female reproductive system? Front Physiol. 2022;13:845156.
12.A comparative analysis of estrogen receptors, ACE2 and cytokines in COVID-19. Front Public Health. 2025;13:1554024.
13.Sex hormones in COVID-19 severity: the quest for evidence and clinical applications. J Cell Mol Med. 2024;28(6):1234–1248.
9/9