Spontaneous preterm delivery in pregnant diabetics: a high risk hitherto "unrecognized".

Preterm delivery (PD)--before the 259th day from the beginning of the last menstrual period--is very frequent in pregnant diabetics (from 50% to 80% or more, personal investigation in progress). In these patients a policy is generally followed of a systematically controlled early delivery. Therefore, one is inclined to think that the high frequency of PD is mainly the consequence of this policy. However, it has been recently pointed out [5] that spontaneous labor accounts for half or more of PD in pregnant diabetics. Moreover in pregnant women with gestational diabetes PD rate due to spontaneous labor is three times higher than in the general obstetric population [5]. A different result emerges from our case study, 1963-1975. Insulin was administered to the maximal tolerated dose both in case of gestational and clinical diabetes [1, 6, 7, 8, 9, 10, 11, 12]. The incidence of PD due to spontaneous labor is 6.7% (7.1% in gestational and 6.1% in clinical diabetes), i.e. no difference from PD rate in general. Since 1974 M. Chartier, Paris, has been adopting the same therapeutic criteria [2]. His results seem to confirm that the risk of PD due to spontaneous labor drastically reduces in pregnant diabetics strictly controlled.