Recently supermodel Chrissy Teigen and her husband, John Legend, announced they were expecting a baby girl with the help of in vitro fertilization (IVF). Ms. Teigen has candidly shared her infertility journey, and been a strong supporter of others struggling to conceive. However, a social media firestorm ensued once she disclosed she and her husband had selected a “little girl” embryo to transfer. What her detractors did not understand is that Ms. Teigen’s IVF doctors had used PGS to make sure her embryos were chromosomally viable. As a result, they also were able to learn the gender of the embryos.


The vast majority of infertility patients who use PGD/PGS are not famous, and many more are using this screening method to ensure they are only transferring embryos with the highest likelihood of success. This can be especially helpful if a patient decides to transfer only one embryo to reduce the chance of having multiples.

Though initially developed to help couples at risk for transmitting a genetic disease, or those who’d suffered multiple miscarriages because of a chromosomal disorder, PGS is today routinely utilized to maximize the probability of pregnancy. This can be extremely reassuring to infertility patients who have experienced the tremendous emotional and financial challenges of several IVF cycles.

Provides Vital Information, Including Gender
PGD/PGS can provide doctors, embryologists and patients with vital information about the health of a patient’s embryos, including the cause(s) of unexplained IVF failure. It can screen for more than 50 debilitating genetic diseases, such as cystic fibrosis, Down syndrome, and Tay-Sachs disease. In addition, PGD/PGS also assesses the gender of the embryos to try to prevent the transmission of a sex-linked genetic disease (a disease carried on the sex chromosome). Of course, this information also can be used to help couples select the gender of their child. Some couples undergo IVF with gender selection for the sole purpose of family balancing. For most, however, knowing the gender of their future unborn child is a happy byproduct of a technique that provides crucial data for pregnancy success.

Safe and Effective Procedure
Embryologists have been using PGD/PGS techniques for more than two decades. PGD/PGS is a safe and effective procedure that has evolved from its original goal of diagnosing for specific conditions to screening for the general health of the embryo. A small number of cells are removed (depending on the time of development of the embryo) using state-of-the-art laser technology. Genetic specialists examine the chromosomes using one of several techniques, including fluorescent in situ hybridization (FISH) and/or the polymerase chain reaction (PCR). FISH involves labeling the chromosomes with a fluorescent tag allowing them to be examined by the embryologist, while PCR enables making multiple copies of the DNA segments.

The embryonic cells continue to divide without the removed cell or cells. Studies have shown that any risk of damage to the embryo is small, and there is no increased risk of birth defects.

Another advancement is comparative genomic hybridization (CGH) that allows the entire DNA sequence in an embryo to be magnified or amplified, providing results on all 23 pairs of chromosomes instead of just one genetic problem.

These methods all bring reassurance to expectant parents that go way beyond being able to paint the nursery the correct paint color. After all, the most important reassurance is that their baby will be healthy.

Self Magazine: February 2016:

HRC Fertility: