Trends in living kidney donation: a compositional shift toward male predominance associated with altruistic donation in Israel

Sex disparity in living kidney donation whereby women donate more frequently than men is a well-documented global phenomenon. In Israel, a comparable pattern historically prevailed until the establishment of the Matnat Chaim (Gift of Life) organization in 2009, which catalyzed a marked rise in altruistic, non-directed donations. The current study assessed how this surge in altruistic donations has reshaped the socio-demographic profile of living kidney donors at our center, with a particular focus on donor sex. We conducted a retrospective analysis of all living kidney donors for recipients under follow-up at Hadassah Medical Center between 1972 and 2021, excluding transplantations performed out of the country. Donors were compared across two periods: 1972–2013 (Period 1) and 2014–2021 (Period 2). Primary variables included donor sex and relationship to the recipient. Secondary variables encompassed marital status, religious affiliation, occupation, place of residence, and physiological parameters. A total of 379 donors were analysed: 134 in Period 1 and 245 in Period 2. The proportion of male donors rose significantly from 52% in Period 1 to 66% in Period 2 ( p = 0.008). In Period 2, altruistic donations constituted 60% of all donations, compared with 0% in Period 1 ( p < 0.0001). The sex ratio within family donations remained essentially unchanged (52% male in Period 1 vs. 54% in Period 2; OR = 1.06, 95% CI 0.62–1.80; p = 0.95), while altruistic donors were 74% male. Altruistic donors were significantly more likely than family donors to be religiously observant (98% vs. 54%; p < 0.001), hold white-collar occupations (63% vs. 34%; p < 0.001), and reside in religious communities (47% vs. 25%; p = 0.01). Female donors were significantly older than male donors (median 50 vs. 39 years; p < 0.001), with only 34% of female donors falling within the reproductive age range (≤ 45 years), compared with 72% of male donors. Among altruistic donors, the ultra-Orthodox group showed the highest male predominance (78%), significantly exceeding the secular group (44% male; OR 4.9, 95% CI 1.76–13.39, p = 0.003). The male predominance now seen among living kidney donors at Hadassah Medical Center reflects a change in donor-pool composition — the emergence of a large, predominantly male, religiously observant altruistic donor pool facilitated by the Matnat Chaim organization — rather than a reversal of the sex distribution among family donors, which has remained stable. This pattern is consistent with two contributing factors within the altruistic pool: practical deferral of women during reproductive years, and the inverted breadwinner structure of ultra-Orthodox households in which women are often the primary income earners; however, donor-level data on motivations, income, and household roles were not collected, so these explanations should be regarded as hypotheses rather than confirmed mechanisms. These findings offer novel insights into the socioeconomic and community-based determinants of sex disparity in living kidney donation. Not applicable. This is a retrospective observational study and did not involve a health care intervention on human participants.