This site became the new on June 19th. Learn more.
Show more Menu IMPORTANT: Listing of a study on this site does not reflect endorsement by the National Institutes of Health. Talk with a trusted healthcare professional before volunteering for a study. Read more... Menu IMPORTANT: Talk with a trusted healthcare professional before volunteering for a study. Read more... Menu
Give us feedback

The Influence of Hormonal Changes During Pregnancy on Corneal Biomechanics in Humans

This study has been completed.
Information provided by (Responsible Party):
Farhad Hafezi, University Hospital, Geneva Identifier:
First received: June 24, 2012
Last updated: March 14, 2016
Last verified: March 2016

The intraocular pressure in the human bulbus requires that the "wall" of the eye shows a certain (bio)mechanical strength. The human cornea represents the anterior portion of this wall. Since several years, there is a growing interest in the ophthalmological community for identifying factors modulating the biomechanical stability of the human cornea. Reasons are twofold: advances in keratoconus research and the increasing numbers of refractive laser surgery procedures with (correspondingly) increasing numbers of complications due to non-respecting the limits of corneal biomechanics.

There is evidence that oestrogen, but also thyroïd hormone changes have a major impact on corneal biomechanics. A number of recent observational studies have reported on keratoconus and refractive laser surgery patients with decompensating biomechanics during pregnancy.

Both hormones also show physiological changes during pregnancy and little is known about the impact of these physiological changes on the human cornea.

The aim of this study is to establish baseline values for physiological changes in the human cornea during pregnancy.

Condition Intervention
Pregnancy Device: Ocular Response Analyzer Device: Scheimpflug measurement Other: Blood sample

Study Type: Observational
Study Design: Observational Model: Cohort
Time Perspective: Prospective
Official Title: Influence of Pregnancy-related Hormonal Fluctuations on Corneal Biomechanics in Humans

Resource links provided by NLM:

Further study details as provided by Farhad Hafezi, University Hospital, Geneva:

Primary Outcome Measures:
  • Correlate oestradiol and TSH plasma changes with changes in corneal CRF and CH and topographical changes [ Time Frame: 15 months ]
    3 examinations during pregnancy (gestation week 10-14, 20-26, and 36-40) and one visit at 6 months after pregnancy

Enrollment: 50
Study Start Date: June 2012
Study Completion Date: June 2014
Primary Completion Date: June 2014 (Final data collection date for primary outcome measure)
Intervention Details:
    Device: Ocular Response Analyzer
    To measure corneal biomechanics, specifically corneal hysteresis (CH) and the Corneal Resistance Factor (CRF). The devise measures in a non-contact manner, by analyzing the deformation of the cornea upon a defined pulse of air.
    Other Name: ORA
    Device: Scheimpflug measurement
    A Scheimpflug camera will be used in a non-contact manner to assess topographical data from the anterior and posterior corneal surface as well as detailed data on corneal thickness.
    Other Name: Pentacam
    Other: Blood sample
    A blood sample will be taken at 6 months after surgery to determine the levels of several hormones. The blood needed to détermine hormone levels during pregnancy will be acquired during the routine examinations that are performed during pregnancy. Here, blood is taken routinely and an additional volume is taken for the purpose of this study.

Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   Female
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population
Pregnant women at the Dept. of Gynecology and Obstetrics of the University Hospital of Geneva

Inclusion Criteria:

  • Older than 18 years
  • Pregnancy confirmed by echography
  • Before gestation week 14

Exclusion Criteria:

  • Pre-existing corneal disease
  • Previous eye surgery
  • Inability to understand the nature of the study
  • Patient with legal guardian
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01629264

University Hospital Geneva
Geneva, GE, Switzerland, 1211
Sponsors and Collaborators
University Hospital, Geneva
Principal Investigator: Farhad Hafezi, MDPhD University Hospital, Geneva
  More Information

Responsible Party: Farhad Hafezi, Professor and Chairman of Ophthalmology, University Hospital, Geneva Identifier: NCT01629264     History of Changes
Other Study ID Numbers: CER-11-180
GE-OPHT-2012-1 ( Other Identifier: University of Geneva, Switzerland )
Study First Received: June 24, 2012
Last Updated: March 14, 2016
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: Undecided

Keywords provided by Farhad Hafezi, University Hospital, Geneva:
refractive surgery processed this record on August 18, 2017