Comparing Anterior Segment Parameters During Pregnancy and Post-Pregnancy

Study Overview
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Brief Summary
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The aim of this study is to evaluate anterior segment changes during and after pregnancy, and compare them with non pregnant healty women

Detailed Description
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Pregnancy is a physiological process in which many systems such as cardiovascular, pulmonary, renal, hematological and visual systems are affected, especially the endocrine system. Many organs, including the eye and orbit, are affected by the physiological interaction between the fetus and the mother. In most pregnant women, these effects are at the physiological level and are temporary; Sometimes it can be pathological and permanent. Hormonal, coagulative and hemodynamic changes are responsible for most of the ocular adaptations. Changes in corneal curvature, sensitivity and thickness are observed during pregnancy. It has been reported that corneal curvature increases with pregnancy, this increase occurs in the last trimester and returns to first trimester values at the end of the breastfeeding period. Although the etiology of this steepening of the cornea has not been clearly clarified, it is thought that it may be due to corneal edema caused by hormonal changes. However, it's not recommended for pregnant women to prescribe contact lenses because their variable keratometric values. A decrease in corneal sensitivity during pregnancy has been detected by esthesiometry in many studies. It decreases especially in the third trimester and returns to normal around the 2nd month after delivery. The corneal thickness measured by pachymeter may increase in pregnant women. some of them had myopic shift. In a study, 83 pregnant women were examined to determine the causes of visual disturbances during pregnancy and postpartum period. Previous studies reported that there was a change in favor of myopia (-0.9±0.3D) during pregnancy and it returned to pre-pregnancy levels in the postpartum period. Unstable refractions were thought to be due to changes in corneal thickness and curvature. As a result, it was stated that the refractive change was temporary and in favor of myopia. It is recommended to wait up to several weeks postpartum before prescribing new eyeglasses [8]. There are various reports about IOP in normal pregnant women. In most of these studies, a decrease was found in IOP during pregnancy. In a prospective study, a decrease in IOP was found in the second and third trimesters of pregnancy, and it was shown that this change returned in the first month postpartum. Before planning an anterior segment surgeries such as cataract and refractive surgery, changes in pregnancy should be taken into account and attention should be paid to surgical timing. The aim of this study is to reveal whether there is a change in anterior segment parameters in pregnancy period

Official Title
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Comparing Anterior Segment Parameters During Pregnancy and Post-Pregnancy

Conditions
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Pregnancy Related

Intervention / Treatment
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* Diagnostic Test: Comprehensive Ophthalmologic Examination


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Ages between 20-40 years Pregnant women with a gestational age less than 14 weeks in the first examination Having no systemic disease before and during pregnancy Having a spherical refractive error of less than 4 diopters, and/or had a cylindrical refractive error of less than 2 diopters Exclusion Criteria: Having systemic disease, having ocular pathology that may decrease visual acuity Usage of systemic drugs or topical ocular drops Usage of exogenous hormones and entered menopause

Ages Eligible for Study
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Minimum Age: 19 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Pregnant Group<br>First trimester pregnant group would be included and will be followed up in second, third trimesters and after pregnancy | Diagnostic Test: Comprehensive Ophthalmologic Examination<br>* Measurements of best-corrected visual acuity, refractive error, intraocular pressure, axial length, slit lamp examination of the anterior segment, dilated fundus examination, and anterior segment parameters,corneal topography<br>* Other names: Non contact tonometry;|
| Control group<br>Age-, sex-matched healthy volunteers | Diagnostic Test: Comprehensive Ophthalmologic Examination<br>* Measurements of best-corrected visual acuity, refractive error, intraocular pressure, axial length, slit lamp examination of the anterior segment, dilated fundus examination, and anterior segment parameters,corneal topography<br>* Other names: Non contact tonometry;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Corneal thickness | Corneal thickness in mikrometer value | 40 weeks | 
| Anterior chamber volume | Anterior chamber volume in mm3 | 40 weeks | 
| Anterior chamber depth | Anterior chamber depth in mm | 40 weeks | 
| Anterior chamber angle | Anterior chamber angle in degree | 40 weeks | 
| Lens power | in diopters | 40 weeks | 
| Anterior flat keratometry | in Diopters | 40 weeks | 
| Steep keratometry | in Diopters | 40 weeks | 
| Mean keratometry | in Diopters | 40 weeks | 
| Tonometry | İntraocular pressure measurement in mmHg | 40 weeks | 
| Best corrected visual acuity assessment | Snellen and logMAR chart | 40 weeks | 
| Blood pressure measurement | Systemic blood pressure | 40 weeks | 
| Auto refractometer | Refractive error measurement in diopter | 40 weeks | 
| Axial length | Axial length in mm | 40 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Pregnancy, Anterior segment, Corneal Topography, Biometry