Parental multiple endocrine Neoplasia Type 1 (MEN 1) is associated with increased offspring childhood mortality

<p><strong>Context:</strong> Information regarding the impact of parental multiple endocrine neoplasia type 1 (MEN 1) on neonatal outcomes is limited to case reports.</p> <p><strong>Objective: </strong>To determine the impact of parental MEN 1 on neonatal outcomes.</p> <p><strong>Methods: </strong>Retrospective cohort analysis of the Tasman 1 MEN 1 kindred stratified by whether birth occurred before (“historical cohort”) or after (“contemporary cohort”) prospective screening commenced. The historical cohort included kindred members born between 1825 and 1984 (<i>n</i> = 341 children with a MEN 1 positive (MEN 1⁺ ) parent and <i>n</i> = 314 children with MEN 1 negative (MEN 1^– ) parents). The contemporary cohort included neonates (<i>n</i> = 52) of MEN 1⁺ women (<i>n</i> = 21) managed at a tertiary referral hospital between 1985 and 2018.</p> <p><strong>Results: </strong>Historical cohort: compared with MEN 1^– parents, children of MEN 1⁺ parents were more likely to die postpartum (HR 4.6, <i>P</i> = .046 at 6 months of age). Excess mortality at 15 years of age was observed for children of MEN 1⁺ mothers (HR 8.50, <i>P</i> = .002) and fathers (HR 3.82, <i>P</i> = .03). Contemporary cohort: neonates of MEN 1⁺ mothers were more likely to have low birth weight (28.9% vs 6.7%, <i>P</i> = .01), be admitted to a higher care nursery (40.4% vs 17%, <i>P</i> = .02), and require a longer median postnatal stay (5 vs 4 days, P = .009) than the Australian average. Isolated antenatal hypercalcemia did not significantly alter neonatal outcomes.</p> <p><strong>Conclusion:</strong> Children with a MEN 1⁺ parent are disproportionately vulnerable postpartum. Neonates of MEN 1⁺ mothers remain vulnerable despite contemporary care. The excess risk was not fully explained by maternal MEN 1 or antenatal hypercalcemia.</p>