Instead of base stat values for the core stats, the level up screen appears to show stats with debuffs applied -- e.g. if a character is suffering from 30-50% reflexes debuff as a result of ongoing pregnancy affecting their belly size, the level up screen will display this reduced value for their reflexes instead of the "full" amount. While not a bug per se, it can be potentially misleading, causing the player to sink more points into temporarily reduced stats if they aren't paying attention.