1587
In a single practice during the 21 years 1971-1991, the incidence of gestational diabetes in pregnancies in which norethisterone was prescribed was 32.4% (22 of 69) in comparison with 7.1% in pregnancies in which the women did not take norethisterone (137 of 1,684) (p < 0.001).
 adverse event: incidence 
Please tell me event type and its trigger word from given type options. Output format is "type: trigger".  Option: adverse event, potential therapeutic event 
Text: {0} 
Answer:
 adverse event: incidence 