Causes of Miscarriage, a Multipart Series; part IV By on October 28, 2013

Part IV Inherited Chromosomal Errors

The Human body is composed of trillions and trillions of cells.

Within almost every cell exists a small capsule called the nucleus.

The nucleus contains 46 delicate threads of genetic material called chromosomes.

Each chromosome is composed of a long molecule of deoxyribonucleic acid (DNA).  DNA is the ubiquitous, double-helix shaped substance made of sugar, protein and a combination of 4 different nucleotide bases.  Everybody’s DNA is made of the same bases, but the order in which they are arranged determines an individual’s characteristics and features.   

A complete set of DNA is derived half from the egg and half from the sperm. Upon fertilization, an embryo takes these two halves and shuffles them together to create a new complete set of DNA.  This set is then replicated indefinitely for each new cell as an organism grows.   Sometimes, during the replication process, too much or too little DNA is copied.  Such a random chromosomal error shortly after fertilization is usually incompatible with life and one of the most common causes of miscarriage.

Another way that an organism can end up with too much or too little DNA is if the egg or sperm provides the wrong amount.   This is called an inherited chromosomal error and while less common than random chromosomal errors, is an important cause of miscarriage. 

Patients with recurrent pregnancy loss should be evaluated for inherited chromosomal errors because if present, they increase the chance that another miscarriage may happen in the future.  To test, blood is taken from both the mother and father and their chromosomes are visualized through a technique called Karyotyping.

Sometimes, instead of finding the usual complement of 46 chromosomes, an apparently normal person may have only 45 chromosomes, one of which has an extra segment of information.  Alternatively, some people have 46 chromosomes with segments that have exchanged from one chromosome to the other.  The result is that a karyotype will have one fewer chromosome or an abnormally placed segment; however, all the chromosomal information is still present.  For the person carrying this chromosomal translocation, their health is not affected.  The problem arises because the sperm or egg contains half of a person’s chromosomal content.  For people with translocations, the chromosomes cannot be evenly split. Thus, an egg or sperm from a person with a translocation will have too much or too little chromosomal information, leading to an embryo with a higher chance of miscarriage.

Fortunately, not all embryos from a parent with a translocation will be abnormal.   The normal embryos can be determined by performing IVF and PGD to check the chromosomal content.  Embryos determined to be normal can then be placed into the uterus while the abnormal embryos are avoided.

If you have questions about miscarriage or fertility treatments in general, feel free to contact us, we’d be happy to speak with you.

Related to This

Doctors

The Center for Fertility and Gynecology

The Center for Fertility and Gynecology provides cutting-edge medical care in a patient-oriented and supportive setting. Drs. Michael Vermesh and Tannaz Toloubeydokhti offer all couples the best possible evaluation, diagnosis, and treatment of male and female infertility. Our experienced physicians are affiliated with:

  • American Association of Gynecologic Laparoscopists
  • ACOG: American College of Obstetricians and Gynecologists
  • American Medical Association
  • ASRM: American Society for Reproductive Medicine
  • Pacific Coast Reproductive Society
  • Resolve: The National Infertility Association
  • SREI: Society for Reproductive Endocrinology and Infertility
  • The Seed Fertility Program

Ready to start your family? Request your consultation today by filling out our online form or calling (818) 881-9800.

Get In Touch

Rate, Review & Explore

Social Accounts Sprite
Google map image of our location in 18370 Burbank Blvd Ste 301 Tarzana, CA

Tarzana Office

18370 Burbank Blvd
Ste 301
Tarzana, CA 91356

Open Today 8:00am - 6:00pm

Google map image of our location in 5353 Balboa Blvd Ste 301 Encino, CA

Our Lab

5353 Balboa Blvd
Ste 301
Encino, CA 91316

Closed Today

Google map image of our location in 9610 Stockdale Hwy  Bakersfield, CA

Bakersfield Office

9610 Stockdale Hwy
Bakersfield, CA 93311

Closed Today

Google map image of our location in 24241 Hawthorne Blvd Ste 201 Torrance, CA

Torrance Office

24241 Hawthorne Blvd
Ste 201
Torrance, CA 90505

Closed Today

Google map image of our location in 415 Rolling Oaks Dr Ste 260 Thousand Oaks, CA

Thousand Oaks Office

415 Rolling Oaks Dr
Ste 260
Thousand Oaks, CA 91361

Closed Today

Tell us a bit about yourself...

(818) 881-9800 Send a message