Gravidity, Parity and GTPAL Notation

Obstetric notation is a compressed history of pregnancy outcomes, not a count of children. That distinction affects risk recognition. A patient may have been pregnant several times without ever reaching 20 weeks, or may have had one pregnancy that produced twins. The number of pregnancies, the gestational age at each outcome, and the number of living children must therefore be reconstructed separately. Gravidity is the total number of pregnancies, including the current pregnancy, regardless of outcome. Each pregnancy counts once, even when it contains twins or higher-order multiples. Parity is the number of pregnancies that reached 20 weeks 0 days of gestation or beyond, regardless of whether the outcome was a live birth or stillbirth and regardless of the number of fetuses. A patient who has had miscarriages, induced abortions, or an ectopic pregnancy but has never reached 20 weeks is nulliparous, or para 0, but is not nulligravid. GTPAL gives more detail than the two-digit gravida/para shorthand. It preserves the gestational age and outcome information that can change current care.