Success Rates: The National Data
It is estimated that the chances of a spontaneous pregnancy during the fertile period of each menstrual cycle is about 20%. This relatively low success rate is often experienced during assisted reproduction as well, although ART results have improved over the past three decades. The 2013 summary data representing all IVF clinics in the United States, published by the Society for Assisted Reproductive Technologies or SART (sart.com), show that about 40% of couples who undergo IVF treatment will achieve a pregnancy and have at least one child as a result of their treatment, provided that the female partner is less than 35 years old and uses her own eggs rather than donated eggs.. When the female partner is 41-42 years old, the chances of becoming pregnant and delivering a baby is significantly reduced to approximately 12%. Delivery rates are also correlated with the number of attempts at IVF and they diminish slightly with each additional attempt. However, couples that have achieved an ART pregnancy and delivery have a slightly higher chance of success in any subsequent attempts compared to those who have never achieved a pregnancy.