Success Rates and IVF Outcomes
Since 1978, hundreds of thousands of live births have occurred via IVF. Recently, Abington Reproductive Medicine celebrated 2,000 live IVF births!
In order to put these success rates in perspective, one must recognize that the human reproductive system is very inefficient. Of 100 eggs exposed to potential fertilization among fertile couples, it is estimated that only 25 will actually produce a healthy baby. The other 75 percent will disintegrate, usually before the first missed period. Therefore, if our IVF team performs as well as mother nature, we can only anticipate a 25 percent success rate. To improve outcomes, we may place multiple embryos back into the uterus. Any remaining normal embryos can be frozen for later transfer.
Congenital anomalies, birth defects, genetic abnormalities, mental retardation and/or other possible conditions may occur in children born through IVF, just as they may occur in children born through natural fertilization. There are absolutely no assurances that these defects will not take place. There does not, however, appear to be any correlation between these conditions and IVF.
As with pregnancies resulting from natural fertilization, an IVF pregnancy may result in a miscarriage, tubal (ectopic) pregnancy or stillbirth. Tubal pregnancies have been reported in approximately five percent of all IVF pregnancies. Should this major complication occur, surgery or medical management will be necessary.
* Clinical pregnancy is defined as pregnancy demonstrated on ultrasound.
Note: A comparison of clinic success rates may not be meaningful because patient medical characteristics, treatment approaches and entrance criteria for ART may vary from clinic to clinic.
Why Pregnancy May Not Occur
There are many reasons why pregnancy may not occur following IVF and embryo transfer. These explanations include, but are not limited to:
- The timing of ovulation may be misjudged, or ovulation may not be able to be predicted or may not occur.
- Attempts to obtain eggs that develop during the monitored cycle may be unsuccessful.
- The eggs obtained may be abnormal or may have been damaged during the retrieval process.
- A semen specimen may not be able to be provided.
- Fertilization of eggs to form embryos may not occur.
- Cleavage or cell division of the fertilized eggs may not take place.
- The embryo may not develop normally.
- Implantation may not occur.
- Equipment failure, infection and/or human error or other unforeseen and uncontrollable factors, which may result in the loss of or damage to the eggs, the semen sample and/or the embryos.