Overview
This lecture reviews the two-digit system of gravity and parity, essential terms in maternity nursing used to assess a woman's obstetric (OB) history, their definitions, prefixes, and how to calculate them using examples.
Gravity
- Gravity (gravida) is the total number of times a woman has been pregnant.
- The outcome of each pregnancy does not matter for gravity; all pregnancies count, including current ones.
- Gravity includes multiple pregnancies (e.g., twins) as one pregnancy each.
Parity
- Parity (para) is the number of pregnancies completed at 20 weeks gestation or more, regardless of outcome (alive or stillborn).
- Only pregnancies completed at or after 20 weeks count toward parity.
- Like gravity, multiple births (e.g., twins) from one pregnancy count as one in parity.
Prefixes and Terms
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"Nulli-" means none or never.
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"Primi-" means first.
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"Multi-" means two or more.
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Nulligravida: never been pregnant.
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Primigravida: pregnant once or currently in the first pregnancy.
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Multigravida: pregnant two or more times.
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Nullipara: never completed a pregnancy at 20 weeks or more.
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Primipara: completed one pregnancy at 20 weeks or more.
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Multipara: completed two or more pregnancies at 20 weeks or more.
Example Scenarios
- If a woman has been pregnant three times, not currently pregnant, and only one pregnancy reached 39 weeks, gravity = 3, parity = 1.
- If a woman is pregnant with twins at 30 weeks (first pregnancy), gravity = 1, parity = 0 (has not delivered yet).
- If she delivers twins at 37 weeks in her first pregnancy, gravity = 1, parity = 1.
Key Terms & Definitions
- Gravity (Gravida) — the total number of times a woman has been pregnant, including current pregnancy.
- Parity (Para) — the number of pregnancies completed at 20 or more weeks gestation, regardless of the number of babies delivered.
- Nulligravida — a woman who has never been pregnant.
- Primigravida — a woman who is pregnant for the first time.
- Multigravida — a woman who has been pregnant two or more times.
- Nullipara — a woman who has never delivered at 20 or more weeks gestation.
- Primipara — a woman who has delivered once at 20 or more weeks gestation.
- Multipara — a woman who has delivered two or more times at 20 or more weeks gestation.
Action Items / Next Steps
- Take the free quiz to review and test knowledge on gravity and parity.
- Review related maternity nursing lectures in the series.