#trimester  a period of three months; especially one of the three three-month periods into which human pregnancy is divided
  supertype:  time_period__period__period_of_time  an amount of time; "a time period of 30 years"; "hastened the period of his recovery"
  part of:  gestation_period
  subtype:  first_trimester__firsttrimester  time period extending from the first day of the last menstrual period through 12 weeks of gestation
  subtype:  second_trimester  time period extending from the 13th to the 27th week of gestation
  subtype:  third_trimester__thirdtrimester  time period extending from the 28th week of gestation until delivery

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