A narrow finding should remain narrow
A 2023 narrative review describes reports of increased progesterone in women with luteal-phase defects. It also includes substantial mechanistic and animal research. These findings cannot establish the same effect in all women or show that a supplement corrects every cause of infertility. [1]
Fertility outcomes remain uncertain
A Cochrane review found only low- to very-low-certainty evidence for supplemental antioxidants in female subfertility. The interventions included many different agents, so pooled findings are not vitamin-C-specific proof. Its March 2026 editorial note reports retractions or concerns affecting nine included studies; editors assessed their removal and retained the overall conclusions. [2]
A higher hormone value is not the whole outcome
A change in progesterone does not by itself establish improved live-birth rates, a suitable dose or long-term safety. Results depend on who was studied and when measurements were taken. Discuss fertility concerns with the treating team rather than using a supplement to interpret or treat one laboratory value. [1][2]
Do not substitute for prescribed progesterone
Vitamin C is a nutrient, not an interchangeable form of progesterone medicine. NHS advises reviewing supplements with the prescriber or pharmacist during progesterone treatment. Imagine a person stops their prescribed regimen after reading a small supplement study: that is a treatment change the evidence does not support. [3][4]
| Evidence | Limit |
|---|---|
| Selected luteal-phase population | Not all women |
| Higher measured progesterone | Not automatically more live births |
| Mixed-antioxidant review | Not isolated vitamin C efficacy |
| Prescribed progesterone | Do not replace with a nutrient |
Sources for this article
- The Importance of Natural Antioxidants in Female Reproduction - PMC
Source consulted: 2026-09-21. This is a reference resource, not a claim that we conducted the studies or tested a product. - Antioxidants for female subfertility.
Source consulted: 2026-09-21. This is a reference resource, not a claim that we conducted the studies or tested a product. - Taking Utrogestan with other medicines and herbal supplements - NHS
Source consulted: 2026-09-21. This is a reference resource, not a claim that we conducted the studies or tested a product. - Vitamin C - Health Professional Fact Sheet
Source consulted: 2026-09-21. This is a reference resource, not a claim that we conducted the studies or tested a product.