Yash Khandwala and Michael Eisenberg: Don’t forget the father!

The increasing success and safety of assisted reproductive technology has extended the reproductive window of men and women. Unfortunately, this triumph of modern medicine—the technology that allows parents to delay childbearing until later in life—has not been without risks. Advanced maternal age has been strongly linked with both infant and maternal morbidity during pregnancy. [1,2] And while little is known about the effects of the father on birth outcomes, he is responsible for half of the offspring’s DNA and likely has a measurable effect on offspring health.

As urologists, we frequently encounter men in their 50s, 60s, and occasionally 70s who are interested in having children. Counseling these patients on the risks of the pregnancy due to advanced paternal age has been challenging due to the dearth of data currently available. When we initially set out to evaluate these risks, we started with the question, “Is paternal age actually rising?” We wanted to first determine if this anecdotal rise in older fathers attempting to conceive children was a national trend throughout the United States or limited to our clinic—in other words, was this worth studying? While ample data on maternal age existed, no paternal analysis was available at a populational level in the US. [3] As we examined the birth certificates for nearly 169 million births occurring within the United States since 1972, one major obstacle we noted was the amount of missing paternal data in birth certificates, especially for certain demographics. [4] As birth data is collected at the maternal level, paternal data is missing in about 10% of cases. This is one reason why it has been challenging for researchers to study the paternal effects on offspring and maternal health.

After confirming that fathers, like mothers, have been getting older since the 1970s, our focus shifted back to the original question of whether or not this posed any risk for the overall pregnancy, the subject of our current study. The father’s role in child birth is often ignored or forgotten, especially in pregnancies involving older mothers who undergo meticulous screening for early fetal loss and chromosomal abnormalities. We discovered that we may no longer be able to ignore the potential impact that older fathers have on their offspring. Our study showed that delaying fatherhood is associated with negative effects on both infants and mothers. While there is still a significant need to evaluate the economic and public health implications of the association between advanced paternal age and pregnancy outcomes as well as the etiology of the association, couples may benefit from some preliminary counseling regarding the modest increase in risk to both mother and infant during pregnancy for older fathers (as well as older mothers).

Yash Khandwala is a urology resident at Stanford Hospital.
Michael Eisenberg is a urologist at Stanford Hospital.


  1. Cleary-Goldman J, Malone FD, Vidaver J, Ball RH, Nyberg DA, Comstock CH, et al. Impact of Maternal Age on Obstetric Outcome. Obstet Gynecol [Internet]. 2005;105(5). Available from: https://journals.lww.com/greenjournal/Fulltext/2005/05000/Impact_of_Maternal_Age_on_Obstetric_Outcome.11.aspx
  2. Andersen AN, Wohlfahrt J, Christens P, Olsen J, Melbye M. Maternal age and fetal loss: population based register linkage study. Bmj. 2000;320(June).
  3. Matthews TJ, Hamilton BE. Delayed childbearing: more women are having their first child later in life. NCHS Data Brief. 2009;(21):1–8.
  4. Khandwala YS, Zhang CA, Lu Y, Eisenberg ML. The age of fathers in the USA is rising: an analysis of 168 867 480 births from 1972 to 2015. Hum Reprod [Internet]. 2017;32(10):1–7. Available from: http://academic.oup.com/humrep/article/doi/10.1093/humrep/dex267/4096427/The-age-of-fathers-in-the-USA-is-rising-an