Large yellow wall clock on a white backgroundIntrauterine insemination (IUI) is a common assisted reproductive technology (ART) used to help couples struggling with infertility to achieve conception. The findings of a new study, however, show that an advanced paternal age may be an indicator as to whether the procedure will be successful.

The Study Results

According to data released earlier this year at the 2014 Annual Meeting of the American Urological Association, or AUA, there is as much as a 20 percent decline for every decade of advanced paternal age of the father. This decline starts as early as when the man is in his 20s.

Dr. Natan Bar-Chama, Mount Sinai School of Medicine in New York, led the study with his colleagues. He and his team studied the results of nearly 19,000 stimulated IUI cycles from their institution that occurred over an eight-year period. The definition for a successful IUI cycle was a live birth. This study is considered the largest to date to track these outcomes for this specific ART procedure.

In general, the idea of a biological clock has always been associated with the female. Because women are born with all the eggs they will ever have, the biological clock is a metaphor for the decline in her egg quality that happens naturally as she ages. In light of this data, however, it appears that men have an equally important biological clock ticking, indicating that sperm quality is also declining at a rapid rate.

IUI is a common ART treatment. In an IUI cycle, your doctor will place sperm in your uterus when you are close to ovulating. When fertility drugs are used to stimulate ovulation, the procedure is called stimulated IUI. Experts agree that while stimulated IUI is often more successful, it also increases the risk of having multiples, which can cause complications for both mother and child. This type of treatment is often recommended for:

  • Male fertility issues, such as a low sperm count or a low motility factor, where the sperm is unable to swim to the egg properly
  • Couples that have a problem with intercourse due to injury, disability or other contributing factors
  • Same-sex or single-parent procedures
  • Women with a case of mild endometriosis, a common condition that affects fertility
  • Unexplained fertility issues

Essentially, this study demonstrates that the success rate of stimulated IUI treatment is likely to be reliant on the age of the prospective parents, both the mother and the father. In order for the cycle to be a success, there needs to be both a healthy egg and sperm. What Dr. Bar-Chama shows is that even though men produce sperm throughout their lives, the sperm they produce later in life is likely not as good a quality as that which they produce when they are younger.

When it comes to IUI, or any ART treatment, most people typically concentrate on maternal age as a determining factor on the success rate. But it appears that the age of the father is also an important factor that will affect the procedure’s outcome. For both father and mother, the ticking of the biological clock is an important consideration when it comes to starting your family.


“Paternal Age a Determinant of Birth Success rates with stimulated IUI.” 22 May 2014. Web. 10 July 2014. <>

“Fertility Treatment: intrauterine Insemination (IUI)” March 2014. Web. 10 July 2014. <>