pregnancy and visual changes

Last edited 05/2018 and last reviewed 01/2022

Physiological changes:

  • changes in spectacle prescription/difficulty wearing contact lenses
    • reduced production of tear fluid occurs in pregnancy
      • increased myopia (shortsightedness) occurs in about 14% of women
        • caused by reduced tear fluid, altered corneal curvature, increased corneal thickness, and influx of water into the lens
        • refraction disorders are marked by myopization, often not very significant and always regressive within six weeks after the childbirth (2)
      • also changes in tear fluid production may cause contact lens intolerance

  • subconjunctival hemorrhage may occur in about 10% of women during and after delivery
    • requires no measures other than check of blood pressure and baseline blood tests (FBC, clotting)

  • intraocular pressure decreases mildly during pregnancy
    • by 2-3 mmHg, under the influence of hormones (mainly progesterone)
    • no physiological, funduscopically visible changes of the retina arise in the course of a normal pregnancy

Pathological ocular changes:

  • ptosis
    • very rare - a few cases of ptosis due to hormonally induced weakening of the attachment of the levator palpebrae have been described
      • benign
      • change must be distinguished from an oculomotor nerve palsy (in which ptosis is accompanied by extraocular muscle weakness leading to diplopia, and by enlargement of the pupil), which requires a further neurological work-up

  • Horner's syndrome (reversible)
    • reported to arise after epidural anesthesia in 0.4% to 2.5% of cases

  • facial nerve palsy
    • probability of development of a transient facial nerve palsy during pregnancy is 38-45 per 100 000 births, or three times higher than at other times

  • central serous chorioretinopathy
    • idiopathic condition involving central retinal detachment
    • arises in 0.008% (4 of 17 000) women in the course of an otherwise unremarkable pregnancy
    • high cortisol concentration during pregnancy is thought to be the main precipitant of this condition
    • usually arises in the third trimester and regresses spontaneously a few weeks to months after delivery

  • hypertensive retinopathy and visual changes in pre-eclampsia/eclampsia
    • pregnancy-related hypertension arises in 5% to 11% of pregnant women
      • 40% to 100% of these patients show signs of hypertensive retinopathy
      • ranging from mild focal retinal vascular spasm to cotton-wool spots and hemorrhages to papilloedema
        • changes, when detected, should prompt further diagnostic and therapeutic steps, even though only 25% to 50% of the affected women are symptomatic (blurred vision, photopsia, visual field defects)
        • retinal changes reflect the severity of hypertension:
          • the most severe changes are seen in (pre-)eclampsia, ranging to reversible serous retinal detachment
        • severe vascular changes in eclampsia, leading to anterior ischemic optic neuropathy (AION) or cortical blindness, are rare
          • cortical blindness and other visual changes resulting from eclampsia may occur
          • generally resolve within hours or days, although subjective visual impairment persists in rare cases

Notes:

  • because of pregnancy related changes in the corneal curvature and thickness, refractive surgery should not be performed during pregnancy or in the first year after delivery

Reference: