Answers are grounded in this paper and cite their sources.
The incidence of preterm delivery was 28.2% of all twin deliveries. Preterm delivery was common in monozygotic twins due to a high incidence of spontaneous rupture of the membranes. In addition, preterm delivery was associated more often with boy rather than girl infants.
No takes yet. Share an insight, caveat, or question.
MacGillivray et al. (1982) studied this question.
Synapse has enriched 10 related papers. Consider them for comparative context: