In 2006, Canadian clinics reported an average pregnancy rate of 35%. A French study estimated that 66% of patients starting IVF treatment finally succeed in having a child (40% during the IVF treatment at the centre and 26% after IVF discontinuation). Achievement of having a child after IVF discontinuation was mainly due to adoption (46%) or spontaneous pregnancy (42%).
Antisperm antibodies (ASA) have been considered as infertility cause in around 10–30% of infertile couples. In both men and women, ASA production are directed against surface antigens on sperm, which can interfere with sperm motility and transport through the female reproductive tract, inhibiting capacitation and acrosome reaction, impaired fertilization, influence on the implantation process, and impaired growth and development of the embryo. The antibodies are classified into different groups: There are IgA, IgG and IgM antibodies. They also differ in the location of the spermatozoon they bind on (head, mid piece, tail). Factors contributing to the formation of antisperm antibodies in women are disturbance of normal immunoregulatory mechanisms, infection, violation of the integrity of the mucous membranes, rape and unprotected oral or anal sex. Risk factors for the formation of antisperm antibodies in men include the breakdown of the blood‑testis barrier, trauma and surgery, orchitis, varicocele, infections, prostatitis, testicular cancer, failure of immunosuppression and unprotected receptive anal or oral sex with men.
The percentage of cycles cancelled between egg retrieval and embryo transfer is an indication of failed fertilization. This figure is halved with ICSI as compared to conventional IVF, indicating that it can indeed improve fertilization when the sperm is at fault. However, there are no differences in pregnancy, miscarriage or live birth rates between conventional IVF and ICSI, indicating overall similar success rates1.
This chart is US national average data on success rates per IVF cycle by female age for 2014. The dark blue line (triangles) shows pregnancy rates per cycle by age. The orange line (circles) shows live birth rates per cycle by age. The rate of singleton live births per cycle is shown by the light blue line. The difference between "pregnancy" rate and "live birth" rate is due to miscarriages.
A woman's age is a major factor in the success of IVF for any couple. For instance, a woman who is under age 35 and undergoes IVF has a 39.6% chance of having a baby, while a woman over age 40 has an 11.5% chance. However, the CDC recently found that the success rate is increasing in every age group as the techniques are refined and doctors become more experienced.
Women are not always the source of a couple's infertility—in approximately one-third of cases, men may have difficulty with conception. In another third of cases, men are a contributing factor, along with female infertility and other problems. Men should be evaluated by a physician if there is a family history of infertility, if they have undergone cancer treatment, if they have small testicles, a swollen scrotum, or a low sperm count, or if they have any other testicular, prostate, or sexual problems.
^ Baker VL, Luke B, Brown MB, Alvero R, Frattarelli JL, Usadi R, et al. (September 2010). "Multivariate analysis of factors affecting probability of pregnancy and live birth with in vitro fertilization: an analysis of the Society for Assisted Reproductive Technology Clinic Outcomes Reporting System". Fertility and Sterility. 94 (4): 1410–6. doi:10.1016/j.fertnstert.2009.07.986. PMID 19740463.