Here are some of the major causes of failed IVF cycles:

• Embryo Quality: The major reason why an IVF cycle is not successful is embryo quality. Many embryos are not able to implant after transfer to the uterus because they are flawed in some way.
• Age of the Eggs: When it comes to IVF, the age of the eggs is more important than the age of the woman having IVF treatment. The quality and quantity of a woman’s eggs, known as her ovarian reserve, begin to get worse as she gets older.
• Ovarian Response: Sometimes a woman’s ovaries don’t respond to the fertility medications strongly enough to produce multiple eggs. Especially if a woman is over 37 or has higher FSH levels she may not produce enough eggs to result in a number of embryos for screening and potential implantation.
• Chromosomal Issues: One of the major factors in IVF failure is chromosomal abnormalities in the embryo. This is true for all human embryos, whether naturally conceived or developed in the embryology lab.
• Lifestyle Factors: Many fertility clinics require women to stop smoking at least three months before starting IVF treatment. Women who smoke need twice as many IVF cycles to conceive and are much more likely to miscarry than women who don’t smoke. Women who are overweight or underweight are less likely to have successful IVF treatment.