A Experimental timeline and representative traces of a stimulus train elicited by 250pA current injection for 300 ms. B, C Fetal CBD exposure decreased the intrinsic excitability of layer 2/3 pyramidal neurons in P14 females but not males (vehicle females: n = 6 cells, 1 mouse; vehicle males: n = 12 cells, 2 mice; CBD females: n = 5 cells, 1 mouse; CBD males: n = 14 cells, 2 mice; female treatment effect: P < 0.0001; Sidak’s multiple comparison, *<0.05, **<0.01). D Fetal CBD exposure did not alter spike thresholds of P14-21 mice (left, vehicle: −39.84 ± 2.613 mV, n = 25 cells, 4 mice; CBD: −35.92 ± 1.523 mV, n = 24 cells, 4 mice; Welch’s t-test, P = 0.2018). Fetal CBD exposure significantly increased membrane potential change (middle, vehicle: 24.23 ± 2.251 mV; CBD: 33.21 ± 1.963 mV; two-tailed t-test, P = 0.0043) and minimum currents (right, vehicle: 110 ± 9.574 pA; CBD: 162.5 ± 11.36; Mann–Whitney, P = 0.0007) required to evoke action potentials. E Resting membrane potential of P14-21 mice remained unchanged following fetal CBD exposure (vehicle: −64.07 ± 2.008 mV, n = 25 cells, 4 mice; CBD: −68.06 ± 1.773 mV, n = 25 cells, 4 mice; Mann–Whitney test, P = 0.1261). F The effect of fetal CBD exposure on changes of membrane potential (vehicle: 20.76 ± 2.826 mV, n = 12 cells, 2 mice; CBD: 35.19 ± 3.963, n = 10 cells, 2 mice; two-tailed t-test, P = 0.0066) and minimum current for action potential firing stemmed from females (vehicle: 100 ± 8.704 pA, n = 12 cells, 2 mice; CBD: 188.9 ± 20.03 pA, n = 10 cells, 2 mice; Welch’s t-test, P = 0.0018). G Resting membrane potential was unchanged in females following fetal CBD exposure (vehicle: −65.97 ± 2.966 mV, n = 12 cells, 2 mice; CBD: −67.16 ± 3.506 mV, n = 10 cells, 2 mice; two-tailed t-test, P = 0.6370). H, I Male mice showed no significant differences in spike threshold (vehicle: −35.81 ± 3.321 mV, n = 13 cells, 2 mice; CBD: −36.65 ± 1.725 pA, n = 15 cells, 2 mice; Mann–Whitney test, 0.7856), change in membrane potential (vehicle: 27.43 ± 3.309 mV; CBD: 32.02 ± 2.115 mV; Mann–Whitney test, P = 0.0648),and minimum currents for action potential spikes (vehicle: 119.2 ± 16.54 pA; CBD: 146.7 ± 12.41 pA; two-tailed t-test, P = 0.1893), or resting membrane potential (vehicle: −63.24 ± 2.820 mV; CBD: −68.67 ± 1.910, Mann–Whitney test, P = 0.0977). *P < 0.05, **P < 0.01, ***P < 0.001; error bars represent SEM. n.s. not significant.