When is a man too old to have a kid?  Risks of “Advanced Paternal Age”

older father holding his child

Women have made so many gains in the 20th and 21st centuries including social, political, economic, and reproductive rights.   Each generation enjoys more benefits than the one before.   Though there is still so much work to be done, one area that has little likelihood of changing is the reproductive window afforded to women.

Getting pregnant, staying pregnant, and delivering a full-term, healthy infant becomes slightly harder each year.  Around 30, many women start to worry, a little.  And by 35, women are noted to be at higher risk.   By the age of 43, the chance of a woman conceiving a pregnancy spontaneously with her own egg is less than 3%, and then the pregnancy is at a much higher risk of complications.

“Elderly” or “Advanced Maternal Age” are terms used for women who are pregnant at or above the age of 35.  These are meant to highlight the extra attention these women need for pregnancy-related complications in both the woman and the fetus.   Developing high blood pressure or diabetes is more likely in women over the age of 35.   Preterm labor, stillbirth, abnormal chromosomes in the fetus, or birth defects are also more common.

As unfair as this may be, we’re now learning that the age of the father matters too.  The proportion of babies born to fathers over the age of 35 has increased dramatically in the last 20 years, by more than 60%. There are many reasons for these changes, including delayed childbearing by many couples, increased life span, and the increased access to assisted reproductive technology (ART).

So, what is “Advanced Paternal Age” and what do we know about it?

APA is commonly defined as age 40 or older, though no formal, universally accepted definition has been accepted.  Even the American College of Medical Genetics (ACMG) has yet to establish a specific age for APA or to recommend any increased screening or counseling for couples where the father is APA.  Though women’s natural fertility ends with menopause, giving us a defined period of time to study, men continue to produce sperm until the very end of their lives, making pregnancy possible from the sperm of 50-year-olds (and 80-year-olds).


There are several issues that affect men as they age related to fertility.  Declining testosterone decreases libido, and sexual frequency and subsequently decreases opportunities for pregnancy.  There are several studies in the literature documenting decreases in semen volume and sperm health in older men compared to 30-year-olds.  Fertility rates have also been documented as lower in men over the age of 50 by 25% or more when compared to men under the age of 50, independent of the age of the woman.  There are also health issues—obesity, tobacco, cardiovascular disease, alcohol use—that increasingly affect sexual frequency and semen quality more significantly at older ages.

Pregnancy outcomes with ART and APA

This is a growing area of research.   There are some studies that show decreased rates of live birth after IVF by 10-20% when the father was over 40 or 50 years of age.   Some studies have also shown increased rates of chromosomal abnormalities in fetuses of fathers over the age of 50.  However, there are also studies that show no difference in outcomes of ART across the various age groups of the father.   This is an area in which we expect a lot more data in the near future.

APA and fetal health

One of the measures of semen that increases with age is sperm fragmentation.  This is associated with chromosomal abnormalities in fetuses.   Studies show that fathers over the age of 40 increase the risk of preterm birth (less than 37 weeks) and very preterm birth (less than 32 weeks).   There are also several studies that show an increased risk of Trisomy 21 (Down’s Syndrome), Klinefelter’s syndrome (XXY), Autism, and other disorders in men over the age of 40.

Fetal health issues that are increased with APA:

  • Trisomy 21 (Downs Syndrome)
  • Klinefelter Syndrome (XXY)
  • Autism spectrum disorders
  • ADHD
  • Schizophrenia
  • Bipolar disorder
  • Cleft palate
  • Neural tube defects
  • Upper limb defects
  • Congenital heart defects
  • Leukemia
  • Central Nervous System tumors

While we don’t have a clear definition of APA yet, there is a growing body of evidence that by the age of 35, there are some clear changes in the reproductive health of men.   There is a measurable decline in fertility, a potential decrease in success with ART, an increased risk of pregnancy complications, and chromosomal and mental health diagnoses in offspring.

We are hopeful to see more published research in this area, increased counseling for couples, and hopefully dedicated public health resources to educating couples about the issues surrounding the increasing ages of BOTH parents when considering conception and pregnancy.

El Camino Women’s Medical Group offers the latest Minimally Invasive Solutions for gynecologic problems.   Drs. Amy TengErika Balassiano, and Pooja Gupta, all members of AAGL (American Association of Gynecologic Laparoscopy) are highly trained and experienced in the field of Minimally Invasive Gynecologic Surgery.   Dr. Erika Balassiano has also completed a Minimally Invasive Gynecologic Surgery Fellowship, under the supervision of world-renowned Dr. Camran Nezhat.


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