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What is a Blastocyst in In Vitro Fertilization?

By Dr. Jesús Alberto Félix Atondo

In vitro fertilization (IVF) is an option for thousands of women who want to have children but need medical intervention to do so.   Although IVF is simply the assisted fertilization of a female’s egg with the sperm of a male, it’s quite a bit more involved than the beginnings of the normal conception process.  In both cases, however,  the product of the egg-sperm union is referred to as blastocyst, which is the collection of dividing cells surrounded by a fluid cavity that develops into an embryo and eventually into a fetus which the mother carries to term.

What is a Blastocyst, and Why is it Important?

Put simply, a blastocyst is the start of an embryo, or embryos, that will mature into a living fetus that will be your baby nine months later.  For that to happen, healthy sperm must fertilize healthy eggs; once that happens, the blastocyst begins to develop and the cells start to divide.  Normally, several days after this occurs, the blastocyst travels down the fallopian tubes to the uterus, where the fetus develops into maturity.  IVF helps this process start.

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Blastocysts in the IVF Process

It’s important to understand exactly how an IVFs can produce healthy, viable blastocysts.  Unlike normal conception, a blastocyst is created through IVF under carefully controlled and monitored laboratory conditions.  It is often the choice of women who have problems within the reproductive system, such as cysts, cancer, endometriosis, or blockage of the fallopian tubes, or other medical reasons to believe they are not capable of attaining a viable pregnancy.  It is also an alternative for women with a decline of egg quality or number, for male partners who have low sperm counts, or in cases where genetic problems in the mother’s history are presented.  The IVF essentially creates an environment in which a blastocyst can get off to a good start.  For some couples, it’s the only answer.

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It all starts with eggs being taken from the ovaries, a process called follicular aspiration.  Those eggs can be immediately fertilized with sperm, or cryo-frozen for future fertilization and implantation.  The eggs are extracted through an outpatient procedure under light anesthesia.  Once fertilized, the eggs are implanted into the uterus—also through an office procedure using light sedation—to begin their development.  This is referred to as a blastocyst transfer. Only the most viable embryos are chosen, and only in small numbers, to reduce the possibility of twins or triplets.  Embryo cells are “graded” for their health and viability; those that are of “A” or “B” quality are generally used; lesser-quality ones carry a greater risk of causing what’s called a “chromosomal error,” which can result in abnormal fetal development.

How does a blastocyst in IVF forms

What Helps A Blastocyst Develop?

The early part of IVF involves fertilization medications to instigate super-ovulation, which produces more, and healthier, eggs that can be used.  A full physical examination and evaluation are usually performed before this step in order to make sure the candidate is healthy and capable of safely carrying a child, as various physical problems can hinder a successful term pregnancy.

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As the cells of the blastocyst continue to develop, the outer edge of begins to form.  This is called a trophectoderm, which is an outer layer of cells that both protects and nourishes the blastocyst.  It begins to appear a few days after fertilization, and eventually will be the formation of the placenta that connects to the uterus.  Once the blastocyst is securely settled into the uterus, the rest of the pregnancy is like any other.

From Blastocyst to Baby

The normal development of embryos depends largely on the health of the mother.  Patients with risk factors, such as diabetes, body weight problems, or sexually-transmitted diseases (STDs) require the supervision of qualified OB-GYN doctors, as do women over the age of 35-40.  Careful monitoring of vital signs, as well as adherence to special diet and lifestyle changes, is required even in the early stages of IVF.  You need a medical care team that can ensure you—and your baby—stay in the best of health all the way through your shared journey.

The Fertility Center, located in Tijuana, is your answer for all stages of the process of IVF in Mexico, and for a number of other reproductive services as well.  Our highly experienced staff of doctors and technicians use the best of fertility treatments to ensure a safe and successful pregnancy.  We also offer a full range of other services, such as routine gynecological exams, pap smears, menopausal treatments, diagnostics, embryo freezing, egg freezing Mexico, intrauterine insemination and high-risk pregnancy care.  We provide services in fertility treatments for men as well.  Contact our fertility specialist Tijuana today to schedule an appointment as you consider one of the most important decisions you’ll make in a lifetime.

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Dr. Jesús Alberto Félix Atondo

Gynecology, Obstetrics and Biology of Human Reproduction Surgeon at the Autonomous University of Guadalajara, specialist Biologist of Human Reproduction by the Mexican Institute of Infertility.

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