As far as i can see this doesn't add up. The Oxford Handbook of Obstetrics and Gynaecology explains the terminology as follows:
Gravida x, para a + b
x= the total number of pregnancies (including this one)
a= the number of births beyond 24 weeks gestation
b= the number of miscarriages or termination of pregnancies before 24 weeks gestation
Given this information, your example means that your lady has had 3 pregnancies (including the current pregnancy if she is currently pregnant). Para 0 means none of the pregnancies were delivered beyond 24 weeks. There has been one termination before 24 weeks. There is therefore one pregnancy unaccounted for in this example.
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