Intro
Many EAs factor children’s effects on their personal impact when deciding whether to have them (example). To offer some insight for potential parents, I tried to summarize the best research I could find on parenthood’s impact on people’s productivity, though I was surprised at the lack of robust literature (especially more recently). The following information comes from four studies: one published in Science[1], one published in Nature[2], one from the Federal Reserve of St. Louis[3], and one published in Social Studies of Science[4]. They all focus on academics and quantitatively measure productivity with research output metrics (the footnotes contain more detail about each).
How parenting impacts productivity
TLDR: The trend for having one child seems to be a short-term reduction in productivity (median: 17%, mean: ~23%) for mothers that peters out after ~10 years. There is usually little effect on fathers, but fathers who are primary caregivers (or otherwise more engaged with their children) suffer similar short-term (<10 year) productivity losses. Each additional child seems to decrease short-term productivity by an additional 11%.
- Science:
- Short-term (<10 years after having children):
- Consistent effects on mothers: The paper finds a ~17%, ~24%, and ~48% decrease in productivity[1] for those in computer science, business, and history, respectively. The authors propose that the different levels of cooperation in these fields may explain the variation in productivity impact—i.e., those in more cooperative fields may suffer lower productivity losses.
- They also note their results likely underestimate the effects because their sample didn’t include parents who left academia (which may have been prompted by their children directly or indirectly)
- Inconsistent effects on fathers lead the authors to conclude there is “no clear evidence” of a short-term productivity decrease for fathers.
- Long-term (>10 years after having children):
- Inconclusive results for both mothers and fathers.
- Federal Reserve of St. Louis:
- Short-term (<12 years after having children):
- Women’s productivity[3] decreased by 15%–17% on average. The total productivity cost of having one, two, or three preteens was 9.5%, 22%, and 33%.
- “Men’s productivity is not associated with their family situation in an economically significant manner.”
- Long-term (>12 years after having children):
- Parenting has no effect on productivity for mothers or fathers, so long as they have their children on purpose after they turn 30 years old.
- Social Studies of Science:
- Overall:
- 8% and 12% decline in research productivity and visibility[4], respectively, for men and women combined. For women, the decrease was 15%.
- To illustrate the cumulative effect of this, mothers were 2 years behind their childless counterparts in the number of papers they published 18 years after having their children.
How to minimize productivity impacts
Have kids later
- Economists who become mothers before 30 suffer a 13% decrease in overall (short- & long-term) productivity[3], whereas those having children after 30 do not (Fed of St. Louis).
- Employment at an institution 100 ranks higher correlates with an additional 1-year delay before having children. However, this might be explained by personality: Perhaps, the type of people who wait to have children are the type of people who become employed at higher-ranked institutions (Science).
Take parental leave
- Taking parental leave shorter than 1 month was associated with a 26.9% improvement in productivity in a US sample but had no statistically significant correlation in a non-US sample (Nature).
- Taking parental leave for 1 to 3 months was associated with a 26.7% productivity improvement in the US sample and a 17.1% productivity improvement in the non-US sample (Nature).
- Taking parental leave for 3 to 6 months was associated with a 17.8% productivity boost in the US sample and a 10.5% productivity improvement in the non-US sample (Nature).
- In the US sample, the advantage disappeared after 6 months, while it disappeared only after 12 months in the non-US sample (Nature).
- Leaves between 6 and 12 months in the non-US sample correlated with a 10.6% boost in productivity.
Be a lazier parent and divide labor between you and your partner
Whether the former will harm your children is another topic (see this 80k podcast episode for an argument it won’t)
- In general, the more engaged parent academics are with their children, the lower their research productivity and impact[2] (Nature).
- Mothers are usually more engaged parents: ~31% of assessed mothers were their children’s primary caregivers, while ~4% of fathers were (Nature).
Have kids on purpose
- Women who unintentionally had children had a 13%–17% decrease in overall (short- & long-term) productivity[3], while there was no overall productivity decrease for those who intentionally had children after turning 30 (Fed of St. Louis).
Work in a cooperative field
- Academics in fields with higher rates of collaboration have reduced productivity[1] losses from children. This link is not necessarily causal, however (Science).
Have fewer children
- Each additional child decreased short-term productivity[3] by an additional 11%, on average (Fed of St. Louis).
- ^
Productivity was measured by the total number of papers published.
- ^
Research productivity was measured by total citations, and impact was measured by citations relative to other papers published in the same field and year.
- ^
Productivity was measured by the total number of papers published, weighted by the impact of the journals they were published in.
- ^
Research productivity was measured by academics' number of published papers, and visibility was measured by their citations per year and the impact of journals that published their papers.
Not sure how much to trust GPT's outputs here (I have not verified it), but I was a bit surprised to find that so many female Nobel prize recipients might (again, GPT might hallucinate) have had children. I think this is more towards anecdotal evidence, but might indicate that just counting number of articles leaves out important information. Perhaps the quality of work stays the same or is even increased by having children, even though the amount of work decreases? At least in my case with my kids, while my hours available for work has decreased, I definitely have not experienced a decrease in quality of my work, and if anything, I feel more invigorated and ideas come easily to me when I am not working.
I also asked GPT to do the same for wealthy, self-made women:
If not already obvious, I am probably at risk of some degree of motivated reasoning given that I already have 2 kids!
I did do 1 or 2 spot checks (felt like this was closer to doing nothing than something so didn't detail this in my comment above). It seemed like the Nobel institute or some other web page had bios on all recipients and that these bios often mentioned kids. But I am quite unsure.
Edit/update: I randomly checked Ohsumi and not sure if GPT is ~racist but it included Ohsumi who it seems probably identifies as male. So that does is at least one mistake in the tables above.