Violet's Story: Trisomy 13 Statistics

After Violet's diagnosis, I began to do as much research as I could.  I'm a planner so I wanted to envision every possible outcome.  The spectrum of the defects related to Trisomy 13 were staggering.

I began to hate statistics as I gathered odds regarding her prognosis.  We had already lost the lottery of her having Trisomy 13 which affects around 1 in 16,000 newborns.  This is where the numbers get confusing. Not only does every website and article list a different number, but that rate only takes into account the babies who are genetically tested.  Some babies born too early or still born never get diagnosed.  Some babies are diagnosed prenatally and the pregnancies are terminated.

Some other statistics that we faced during her pregnancy (again, these vary and are gathered from a variety of sources):
- 95% of babies with Trisomy 13 are miscarried or born still.
- 82% of babies born alive with Trisomy 13 die within the first month of life.
- The median age for a baby with Trisomy 13 is just under 3 days.  I've also seen this averaged as 2.5 days which is exactly Violet's lifespan.
- 95% of those born alive die within the first six months of life.
- Trisomy 13 is the third most common trisomy following Trisomy 21 (Down Syndrome) and Trisomy 18.
- Most cases are full Trisomy 13, which means that all cells in the body are affected.  Children that usually survive longer have mosaic T13, which means that only some of their cells are affected.  Violet had full Trisomy 13.
- A small proportion of Trisomy 13 diagnoses are translocations.  This means that the extra genetic material on the 13th chromosome came from another chromosome.  Violet was a translocated case.
- Most cases of Trisomy 13 are sporadic and happen at conception with no genetic predisposition, but some can be caused by the egg or the sperm.  Translocations are more likely to be genetic.  We had testing done and Violet's case was "de novo" meaning it happened spontaneously when she was conceived.  Mr. SPS and I are not carriers but this was a huge worry and concern during Violet's pregnancy until we ruled it out.  Because of the fact that Violet had Trisomy 13, we will have a slightly greater risk of having another Trisomy baby, but only that of anyone else with Advanced Maternal Age (35+ even though I am not yet 35).  The rate is 1% but can sometimes be seen as even lower.
- Race seems to have no effect on the rate of Trisomy 13.
- Girls with Trisomy 13 tend to be born alive and live slightly longer than boys.

Violet's neonatologist cautioned me to allow her to overcome each hurdle one at a time without looking too far into the what ifs. Every day that she wasn't still born was a battle she won.  Every week that she wasn't born premature was allowing her tiny body to grow stronger inside of me.  Every minute that I wondered if she was already gone, then felt her super strong kicks kept reassuring us that we might get some time with our baby while she was still alive.

None of these confusing numbers explained to us who Violet really was: our sweet, loved girl.