Changes in vision during pregnancy

Vision during pregnancy may change due to fluid retention, an increase in blood volume, hormonal changes and other physical changes which take place during pregnancy. These are often temporary changes that resolve after the baby’s birth or after maternal lactation. Vision changes are usually minor and they do not tend to require a change in eyeglass prescription. There are several types of vision changes. Alterations in vision may be classified into three categories:

Physiological changes

• Corneal changes. Due to fluid retention, physiological changes affecting the cornea may occur and lead to a decrease in corneal sensitivity or to an increase in corneal curvature and thickness. This type of changes occur at the end of pregnancy and may cause temporary alterations in refraction. Therefore, undergoing vision correction surgery or refractive surgery is not recommended during pregnancy. Moreover, pregnancy may also induce dry eye syndrome, due to an alteration of some lachrymal cells, which may lead to contact lens intolerance until several weeks after the child’s birth.

• Changes in intraocular pressure (IOP). During the second half of pregnancy, a decrease in vision in healthy eyes may occur. In patients with ocular hypertension, the decrease may even be higher. This type of changes are usually reverted during the two months following the delivery, and IOP levels go back to pre-pregnancy levels.

• Changes in eye adnexa. Eye adnexa may be affected by chloasma, a hormone-mediated increase in pigmentation that affects the areas surrounding the eyes and the cheeks. It usually resolves after delivery. A ptosis (droopy eyelid) may also occur due to hormone-related changes, the stress, and the delivery.

Pregnancy-related eye diseases

• Preeclampsia and eclampsia. Pregnant women may suffer from preeclampsia, that causes arterial hypertension and high level of protein in urine from the 20^th week of pregnancy. This condition may include changes in vision, and even temporary vision, vision of spots or flashing lights, light sensitivity and blurred vision ad some of its symptoms.

• Central serous chorioretinopathy. Some pregnant women may suffer from the acute form of this disease, that causes blurred vision, perception of a central spot, straight lines that seem to be bent or troubles when reading.

• Occlusive vascular diseases. Some cases of vascular retinal alterations with vision loss in both eyes have been documented during the immediate postpartum period.

Preexisting eye diseases and conditions

• High and medium degree of myopia. Close vision monitoring must be carried out in order to avoid any complications, especially during delivery.

• Diabetic retinopathy. Women suffering from diabetic retinopathy may experience a disease worsening during pregnancy, although it may go away after delivery. Other conditions, such as preeclampsia, may exacerbate even more this disease.

• In case the patient suffers from chronic non-infectious uveitis, pregnancy may reduce the outbreak incidence, possibly due to hormonal effects.

Even though there is a wide range of eye diseases that may have a connection with pregnancy, most of them are resolved during the postpartum period. Its diagnosis and treatment may include monitoring benign findings, referring the patient to another specialist or applying a medical or surgical treatment. Therefore, it is advisable to have the vision examined during pregnancy, especially in case of preexisting eye diseases.