Vision changes are a common and temporary experience during pregnancy. The body undergoes profound physiological changes, and these changes often extend to the eyes and visual system. While most alterations are mild and resolve after delivery, understanding the causes can prevent unnecessary worry. This overview explains the mechanisms behind these visual shifts and helps distinguish between normal symptoms and signs requiring immediate medical attention.
The Underlying Causes of Visual Changes
The primary drivers behind vision changes during pregnancy are hormonal fluctuations and generalized fluid retention. Increased levels of hormones, particularly estrogen and progesterone, directly influence the eye’s delicate structures. Receptors for these hormones are present in the cornea and tear glands, making them susceptible to systemic changes.
Fluid retention, which often causes swelling in the hands and feet, also affects the cornea, the clear front surface of the eye. This extra fluid can increase corneal thickness and curvature, particularly in the second and third trimesters. This transient swelling subtly alters the eye’s refractive power, affecting the ability to focus light onto the retina. Hormonal shifts also affect the glands responsible for producing the components of the tear film, leading to ocular surface discomfort.
Common Temporary Vision Alterations
One of the most frequently reported visual alterations is increased dry eye sensation and discomfort. Hormonal fluctuations disrupt the stability and composition of the tear film. This disruption can lead to a gritty, burning, or scratchy feeling in the eyes, often exacerbated during the later stages of pregnancy.
The mild swelling of the cornea due to fluid retention can cause a slight, temporary change in refractive error, often manifesting as minor blurriness or the feeling that a current prescription is incorrect. This shift in corneal shape is usually minimal and does not warrant a permanent change in corrective lenses.
Because of the changes in corneal thickness and curvature, many contact lens wearers experience increased intolerance or discomfort. The contact lens may no longer fit properly on the altered corneal surface, making the lenses feel scratchy or dry. These common alterations are self-limiting, resolving spontaneously after delivery.
Vision Changes Requiring Immediate Medical Attention
While many visual changes are benign, certain symptoms signal serious pregnancy complications and require immediate consultation with a healthcare provider. Sudden onset of severe, persistent blurring of vision is one such warning sign. This symptom, along with seeing flashing lights, spots, or new floaters, is associated with preeclampsia.
Preeclampsia is a blood pressure disorder that develops after 20 weeks of pregnancy, and its effects on the visual system can be severe. Other serious signs include loss of peripheral vision, double vision, or temporary total vision loss. These may indicate issues with the retina or the brain’s visual cortex due to high blood pressure.
Individuals with pre-existing diabetes or gestational diabetes must be closely monitored, as pregnancy can accelerate the progression of diabetic retinopathy. Any rapid, significant change in visual acuity or sustained, severe blurriness must be reported immediately, as it may indicate bleeding or fluid leakage in the retina.
Managing and Treating Pregnancy-Related Vision Issues
For common dry eye symptoms, the safest management strategy involves using non-prescription artificial tears. These drops supplement the natural tear film and provide lubrication to the ocular surface, offering relief from irritation and dryness.
It is recommended to avoid getting a new permanent prescription for glasses or contact lenses during pregnancy. Since refractive changes are caused by temporary fluid retention, the prescription will likely revert to the pre-pregnancy state postpartum. If vision blurriness significantly impairs daily life, a temporary, low-cost pair of glasses based on the current change may be considered instead of a long-term investment. These temporary vision changes typically resolve within weeks to a few months after delivery, as hormone and fluid levels return to their non-pregnant state.