There is the vibe that it will be a "bearing year". The things that can be managed are consistency of feeding for ewes carrying multiples. 4 day shifts were protective compared with daily shifts. In one Otago trial it is assumed the gradual intake rather than 2 hours gorging and then sitting down for long periods, is why the longer shifts help prevent bearings. Mid pregnancy shearing has been shown to be protective against bearings. Iodine and salt appear to have some role in some cases, anecdotal evidence suggests LSD drench may also reduce bearigns. Exercise, slope and extremes of body condition are involved. Weight gain post mating and carrying triplets were among the biggest risk factors....but we can't do much about that now. It is a frustrating and complex issue worth discussing with your vet.