Vision changes are a common, though often unexpected, physical change during pregnancy. Many expectant parents notice temporarily blurred vision or significant dry eye discomfort. These fluctuations are primarily due to dramatic hormonal shifts and increased systemic fluid retention. As a result, people who rely on corrective lenses often question whether they should update their prescription. Understanding the underlying causes and the safety of the examination process helps guide the decision regarding new eyewear.
How Pregnancy Affects Vision
Physiological changes during pregnancy directly impact the structural components of the eye. Increased fluid retention can cause the cornea—the transparent front surface of the eye—to slightly swell. This swelling increases corneal thickness and curvature, altering how light is focused onto the retina.
These refractive changes often result in a temporary shift toward nearsightedness (myopia), making distant objects appear blurred. Because corneal shape is the basis for an accurate prescription, a new prescription based on this temporary change would only be accurate for a short period.
The hormonal environment also disrupts the lacrimal system, which produces tears. Increased estrogen and progesterone, along with reduced androgens, decrease tear film quality and quantity. This reduced lubrication causes or exacerbates dry eye syndrome, resulting in a gritty feeling and potential contact lens intolerance.
Safety Considerations During Eye Exams
For pregnant individuals, the safety of the comprehensive eye examination is a primary concern, particularly regarding diagnostic eye drops. Routine equipment, such as the slit lamp microscope or the instrument used to check eye pressure, poses no risk to the fetus. The main safety consideration involves mydriatics, the drops used to temporarily dilate the pupil for a thorough view of the back of the eye.
While occasional dilation is considered safe, eye care professionals prefer using the lowest effective dose of shorter-acting drops. Medications like tropicamide or cyclopentolate are favored. Tropicamide is classified as a Category C drug, meaning it should only be used when the potential benefit outweighs any theoretical risk.
If dilation is medically necessary, techniques like punctal occlusion minimize medication absorption into the bloodstream. This involves pressing lightly on the inner corner of the eye after drops are administered, blocking drainage into the nasal cavity. Informing the eye care professional about the pregnancy status allows for appropriate safety precautions.
When to Update Your Prescription
Because the changes in vision are typically temporary and related to fluid and hormonal fluctuations, obtaining a new prescription during pregnancy is often unnecessary and can be wasteful. A new prescription based on the temporary corneal change would only be accurate until the eye returns to its pre-pregnancy state.
It is generally recommended to wait until at least eight weeks postpartum before getting new corrective lenses. This ensures the body’s fluid and hormonal levels have normalized. Vision stability typically returns within a few months after delivery, generally between six weeks and twelve months postpartum. If breastfeeding, the return to baseline vision might take longer due to elevated hormonal activity.
Specific vision changes require immediate medical attention, regardless of the stage of pregnancy. Sudden, severe blurring, double vision, flashing lights, or a significant increase in floaters can signal a serious underlying condition. These symptoms may indicate complications such as preeclampsia or the worsening of pre-existing conditions like diabetic retinopathy. Any acute or dramatic change necessitates an immediate consultation with an eye care provider.