<prompt> AG2P1 to female has a history of previous preterm birth at 32 weeks. The percentage chances of preterm birth in this pregnancy are:5101525  <response>: Ans. is c, i.e. 15Ref. Williams Obs 24e, p 841Recurrent spontaneous preterm births according to prior outcomeBirth outcomeSecond birth 34 weeks First birth 35 weeks5First birth 34 weeks16First and second birth 34 weeks41 