Recurrence of placental dysfunction disorders across generations

Objective Knowledge about the causes of placental dysfunction disorders is limited. We performed an intergenerational study, focusing on the risks of placental dysfunction disorders in mothers and fathers who had been born small for gestational age (SGA). Study Design Using linked generational data from the Swedish Medical Birth Register from 1973-2006, we identified 321,383 mother-offspring units and 135,637 mother-father-offspring units. Results Compared with mothers who had not been born SGA, mothers who had been born SGA had the following adjusted odds ratios: late preeclampsia, 1.41 (95% confidence interval [CI], 1.26–1.57); early preeclampsia, 1.87 (95% CI, 1.38–2.35); placental abruption, 1.60 (95% CI, 1.23–2.09); spontaneous preterm birth, 1.11 (95% CI, 1.00–1.23); and stillbirth, 1.24 (95% CI, 0.84–1.82). Compared with parents who had not been born SGA, the risk of preeclampsia was more than 3-fold increased if both parents had been born SGA, whereas if only the mother had been born SGA, the corresponding risk was increased by only 50%. Conclusion There is an intergenerational recurrence of placental dysfunction disorders on the maternal side and most likely also on the paternal side.