The idea that risk for psychiatric disorders may be transmitted intergenerationally via prenatal programming places interest in the prenatal period as a critical moment during which intervention efforts may have a strong impact, yet studies testing whether prenatal interventions also protect offspring are limited. The present umbrella review of systematic reviews and meta-analyses (SRMAs) of randomized controlled trials aimed to synthesize the available evidence and highlight promising avenues for intervention. Overall, the literature provides mixed and limited evidence in support of prenatal interventions. Thirty SRMAs were included. Of the 23 SRMAs that reported on prenatal depression interventions, 16 found a significant effect (average standard mean difference = −0.45, SD = 0.25). Similarly, 13 of the 20 SRMAs that reported on anxiety outcomes documented significant reductions (average standard mean difference = −0.76, SD = 0.95 or −0.53/0.53 excluding one outlier). Only 4 SRMAs reported child outcomes, and only 2 (of 10) analyses showed significant effects of prenatal interventions (massage and telephone support on neonatal resuscitation [relative risk = 0.43] and neonatal intensive care unit admissions [relative risk = 0.91]). Notably missing, perhaps due to our strict inclusion criteria (inclusion of randomized controlled trials only), were interventions focusing on key facets of prenatal health (e.g., whole diet, sleep). Structural interventions (housing, access to health care, economic security) were not included, although initial success has been documented in non-SRMAs. Most notably, none of the SRMAs focused on offspring mental health or neurodevelopmental outcomes. Given the possibility that interventions deployed in this period will positively impact the next generation, randomized trials that focus on offspring outcomes are urgently needed.