Info - Spinning my head against obstetric - Gravida/para/abortus

Understanding Gravida/para/abortus.

Just browsing through the obstetric notes - find these one - gravida, para, abortions, living children.

What is it all about?
Wanting to know more - i'd come to an Ask.com wiki.

Gravida/para/abortus (GPA), or sometimes just gravida/para (GP), is a shorthand notation for a woman's obstetric history.

Ok. That does it with the def! How is it numbering done?

• Gravida indicates the total number of times a woman has been pregnant, regardless of whether these pregnancies were carried to term. A current pregnancy, if any, is included in this count.
• Para indicates the number of viable (>20 wks) births. Pregnancies consisting of multiples, such as twins or triplets, count as ONE birth for the purpose of this notation.
• Abortus is the number of pregnancies that were lost for any reason, including induced abortions or miscarriages. The abortus term is sometimes dropped when no pregnancies have been lost.

Later on that article:

Therefore, the history of a woman who has had two pregnancies (both of which resulted in live births) would be noted as G₂P₂. The obstetrical history of a woman who has had four pregnancies, one of which was miscarried, would be noted as G₄P₃A₁. That of a woman who has had one pregnancy of twins with successful outcomes would be noted as G₁P₁. 

Later on @ Ask.com.