Many women use hormonal contraceptives and they are safe for most women to use or be on. However, in the last couple of years, researchers have been taking a closer look at the possible effects that these hormones have on both the body as well as the eyes of women.

Here are some instances of what has been found to date based on very large scale studies conducted recently. 

The Big Study That Raised Attention (2021)

A very large study followed nearly 5 million women aged 15 to 45 for about ten years. Because of its size, doctors and researchers take its findings seriously.

What they found:

• Women who regularly used hormonal birth control were about 2.7 times more likely to be diagnosed with dry eye disease than women who did not use it.
• The risk was not the same for everyone.
• Women who had used many different types of birth control pills over time had the highest risk.

Why this matters

When risk rises step by step with more exposure, researchers call this a dose–response pattern. It suggests the link may be real and biologically meaningful, not just coincidence.

Newer Findings: Changes Deeper in the Eye (2025)

More recent studies used advanced eye scans to look beyond surface dryness.

What researchers reported:

• Women who used oral contraceptives for more than one year showed thinning in the macula (the central part of the retina responsible for sharp vision).
• They also showed thinning of the retinal nerve fiber layer, which carries visual signals to the brain.

Important note

These findings are still early. Researchers are watching closely to understand whether these changes are clinically significant and who might be most affected.

A Possible Biological Explanation (2023)

Scientists have also been studying why this might happen.

Here is the simple version:

• The eyes need a thin oily layer in tears to prevent fast evaporation.
• This oil is produced by tiny glands in the eyelids (Meibomian glands).
• These glands depend partly on androgen hormones to work properly.
• Some estrogen-containing birth control methods may reduce androgen activity.

What could follow:

Less oil means tears evaporate faster, which makes dry eye symptoms more likely. This mechanism fits well with what doctors are seeing in large population studies.

What About Blinking?

Blinking is also thought to be controlled by brain chemistry, particularly dopamine. As synthetic estrogen can affect these systems, scientists are looking into whether it might impact the blinking behaviour of a subset of users. This research is ongoing and there is not yet any evidence that confirms an association.

What Scientists Agree On So Far

Across studies from 2021 to 2025, several points are becoming clearer:

• Hormonal birth control use is linked with higher rates of dry eye diagnosis.
• Risk appears to increase with longer or more varied exposure.
• Hormonal effects on the eyelid oil glands are a leading explanation.
• Early imaging studies suggest there may be deeper eye changes, but more research is needed.

Most importantly, these studies show association, not definite cause.

What We Still Don’t Know

Researchers are still working to answer:

• Who is most at risk
• Whether the retinal changes are reversible
• Which contraceptive types have the strongest effects
• The long-term clinical importance of these findings

More long-term studies are underway.

The Bottom Line

Research shows an expanding association between certain forms of hormonal contraception (i.e. oral contraceptives) and visual changes—especially dry eye syndrome. There is still much to learn about the nature of this connection and its implications for the long-term health of the eyes. 

At this point the take-home message from this research is to become more aware of possible eye changes due to hormonal contraceptives and to continue to monitor the effects over time; no need for alarm at this time.