{
  "id": 2986079,
  "title": "Childhood Exposure to Joint Custody Reforms and Adult Family Formation",
  "url": "https://urgent.news/2026/08/24/childhood-exposure-to-joint-custody-reforms-and-adult-family-formation",
  "topic": "science",
  "section": "Science",
  "published": "2026-08-24T09:30:37.000Z",
  "source": {
    "name": "Marginal Revolution",
    "slug": "marginal-revolution",
    "url": "https://marginalrevolution.com/marginalrevolution/2026/08/childhood-exposure-to-joint-custody-reforms-and-adult-family-formation.html"
  },
  "original_language": "en",
  "account": "The recent study by Daniel Fernández-Kranz and Sébastien Fontenay delves into the impact of joint custody reforms on adult family formation. The researchers used staggered adoption patterns across US states and analyzed a substantial data set of 13 million American Community Survey (ACS) observations. Their findings reveal that exposure to joint custody in childhood leads to a 7% reduction in adult fertility, affecting both men and women equally. This effect is primarily due to a decrease in parenthood and couple formation.\n\nInterestingly, the impact is sub-additive within couples, meaning the combined effect on fertility is less than the sum of individual effects. Moreover, exposed individuals tend to assortatively match, indicating a preference for similar family structures in their adult relationships. The study's conclusions align with a broader trend in the US fertility decline, which is increasingly driven by rising childlessness and declining couple formation, rather than smaller family sizes among parents. This research, conducted by Fernández-Kranz and Fontenay, sheds light on how childhood experiences can shape individuals' preferences and behavior when forming families as adults.",
  "summary": "Joint custody reforms are among the most consequential family-law changes for children, yet little is known about their long-term effects. Exploiting staggered adoption across US states and 13 million ACS observations, we show that childhood exposure reduces adult fertility by 7 percent, symmetrically for women and men and operates primarily through lower parenthood and couple […] The post…",
  "key_points": [
    "Childhood exposure to joint custody reforms reduces adult fertility by 7%.",
    "Impact is sub-additive within couples, less than the sum of individual effects.",
    "Exposed individuals prefer similar family structures in adult relationships."
  ],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}