Women's physiology changes markedly during normal pregnancy. The most distinct alterations occur in the hormonal and cardiovascular systems. There is a dramatic increase in both estrogen and progesterone. Blood volume starts to increase in the first gestational period and reaches a peak in the third trimester.

The physiologic ocular changes during pregnancy are mainly the result of hormonal and blood volume increase, and then are usually marked in the third trimester.

Ocular anterior segment changes during pregnancy are the followings

• Melanogenesis of eyelid and facial skin -> melasma
• Cellular alteration of lacrimal and meibomian gland -> dry eye symptoms
• Increased corneal thickness and corneal curvature -> contact lens intolerance
• Increased lens thickness -> loss of accommodation
• Decreased intraocular pressure -> better glaucoma control There are few studies of posterior changes in pregnant women. Many limitations of previous publications includes lack of internal control and no data of postpartum contraception. However, choroidal thickness seems to be thicker in pregnant women than non-pregnant women. The other changes are non-inclusive.

Inclusion Criteria:

• Healthy pregnant women
• Age > 18 years
• Gestational age < 12 weeks
• Written informed consent

Exclusion Criteria:

• High risk pregnancy such as multifetal pregnancy and preeclampsia
• History of vitreoretinal diseases such as retinal vasculitis
• History of intraocular laser treatments or intraocular surgeries
• History of systemic diseases such as diabetes mellitus and thyroid disease
• Refractive error; spherical equivalence > 4 diopters
• Clear ocular media
• Could not be taken the images by non-dilated pupil

Withdrawal Criteria:

• Preterm labor; gestational age < 34 weeks
• Multifetal pregnancy was demonstrated by ultrasound
• Severe labor and delivery complications such as
• Severe postpartum complications such as postpartum bleeding
• Taking hormone during the follow-up period