Genetic Testing for Endometrial Receptivity (ERA) – Prenatal Genetic Diagnosis

Genetic Testing for Endometrial Receptivity (ERA) – Prenatal Genetic Diagnosis

The Endometrial Receptivity Test (ERA) is an advanced technique used to assess the genetic readiness of the endometrial lining to receive an embryo during in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI). This test aims to determine the optimal implantation window, thereby increasing the chances of a successful pregnancy.

How Does the ERA Test Work?

The ERA test analyzes the genetic expression of endometrial cells to determine whether the lining is in the correct phase for embryo implantation. This is done through the following steps:

1. A biopsy of the endometrial lining is taken during the menstrual cycle using a thin catheter.
2. Genetic expression analysis is performed on over 200 genes associated with endometrial receptivity.
3. Determining the personalized implantation window, which is the optimal period when the endometrial lining is most receptive to embryo implantation.

Importance of ERA in Infertility Treatment

• Helps improve IVF success rates, especially for women who have experienced repeated implantation failure without an apparent cause.
• Reduces the risk of embryo loss due to transferring embryos at an unsuitable time in the menstrual cycle.
• Provides a personalized approach to treatment by identifying the best timing for embryo transfer.

When is the ERA Test Recommended?

The ERA test is suggested in the following cases:

• Repeated implantation failure despite the transfer of high-quality embryos.
• A history of recurrent miscarriage without a clear explanation.
• Suspicion of irregular implantation windows in the endometrial lining.

Limitations of the ERA Test

• Does not address fundamental infertility issues such as poor egg or sperm quality.
• Requires an endometrial biopsy, which may cause mild discomfort for some women.
• Not necessary for all women and is primarily recommended for those with repeated implantation failure.

Prenatal Genetic Diagnosis

Prenatal genetic diagnosis involves a series of tests conducted during pregnancy to detect genetic disorders and fetal abnormalities before birth. These tests help determine whether the fetus has hereditary health conditions that may affect its growth and overall well-being after birth.

Types of Prenatal Genetic Testing

1. Non-Invasive Prenatal Testing (NIPT)

• Analyzes free fetal DNA (cffDNA) in the mother’s blood to detect conditions such as Down syndrome (Trisomy 21), Edwards syndrome (Trisomy 18), and Patau syndrome (Trisomy 13).
• Safe and poses no risks to the mother or fetus.
• Typically performed after the 10th week of pregnancy.

2. Invasive Prenatal Testing

These tests are conducted if initial screenings indicate potential genetic abnormalities or if there are hereditary risk factors. They include:

1. Chorionic Villus Sampling (CVS)
   • A sample from the placenta is collected between weeks 10-13 of pregnancy.
   • Used to diagnose genetic disorders such as Down syndrome, cystic fibrosis, and thalassemia.
   • Carries a slight risk of miscarriage.
2. Amniocentesis
   • A small amount of amniotic fluid surrounding the fetus is extracted between weeks 15-20 of pregnancy.
   • Used to detect chromosomal abnormalities, certain genetic diseases, and neural tube defects.
   • May carry a slight risk of miscarriage.

Importance of Prenatal Genetic Testing

• Early detection of genetic conditions that may affect fetal health.
• Allows parents to make informed medical decisions regarding the pregnancy.
• In some cases, it helps in planning fetal treatments within the womb.

When is Prenatal Genetic Testing Recommended?

• If there is a family history of genetic disorders.
• In pregnancies occurring after the age of 35, as the risk of chromosomal abnormalities increases.
• If initial screening results indicate the possibility of a genetic disorder.
• In consanguineous marriages, where the risk of inherited diseases is higher.