Gravidity and parity are important parts of a complete obstetric history. To put it simply:

• Gravidity (gravida) is the number of times a patient has been pregnant. This includes a current pregnancy
• Parity (para) is the number of times a patient has given birth to a viable child
• Abortus is the term used to describe a pregnancy that ended for any given reason, including both abortions and miscarriages. A key thing to remember is that when scoring a Mother's Gravida/Para, you drop the Abortus portion if it's zero. 
• These numbers may be different due to a previous miscarriage, a previously terminated pregnancy (abortion), or because the patient is currently pregnant.

For example:

• A woman who has had 3 pregnancies and 2 live births is a Gravida 3, Para 2 (or G3P2)
• If she is currently pregnant again, she becomes a Gravida 4, Para 2
• If she successfully delivers her 3rd child, she becomes a Gravida 4, Para 3

Even though there are multiple fetuses involved, multiple gestation pregnancies (twins, triplets, etc) only count as a single event

This information is important for a few reasons:

• A patient’s first pregnancy is often much different than subsequent pregnancies and carries unique risks
• Each pregnancy and birthing event affect a mother’s reproductive organs in a way that may alter their risk of complications
• Certain risks are associated with having several previous pregnancies

Nullipara is a patient who has never given birth

Primigravida is a patient experiencing their first pregnancy

• Patients in their first pregnancy are much more likely to experience pre-eclampsia
• The first stage of labor (dilation) tends to be much slower in the first pregnancy and other stages may be prolonged as well]
• Labor is generally understood to be more difficult in general

Primipara is a patient who has given birth once

Multigravida is a patient who has been pregnant 2 or more times

• When a patient has been pregnant in the past we should ask about previous pregnancies
• Previous complications (preeclampsia, hemorrhage, breech presentation, etc)
• Length of labor
• Method of delivery (vaginal vs cesarean section)

Multipara (multiparous) is a patient who has given birth 2 or more times

Grand Multigravida is a patient who has been pregnant 5 or more times

Grand Multipara is a patient who has given birth 5 or more times

• Grand multiparty comes with a significantly increased risk of several complications

• You respond to the home of a 19-year-old female who is having a seizure. The patient’s spouse reports that the patient is 32 weeks pregnant. The spouse adds that this is the patient’s first pregnancy. 
• This patient is G1 P0. Because this is the patient’s first pregnancy, the patient is Gravida 1. You may also describe her as primigravida. Because the patient has never given birth, the patient is Para 0. You may also say the patient is nulliparous.

• You are treating a 34-year-old female who appears to be in active labor. She reports she gave birth to 3 previous children who were all delivered vaginally. She also reports a previous miscarriage and another pregnancy that was terminated.
• This patient is G6 P3. For gravidity, we must count the 3 children who were delivered, 2 additional pregnancies she did not carry to term, and her current pregnancy. This results in a Gravida 6. Because the patient has delivered 3 children to term, the patient is Para 3

• You respond to the home of a 37-year-old female with severe abdominal pain and uterine bleeding. The patient reports she has 7 children which include 2 sets of twins, all of whom were delivered by caesarian section. The patient denies any previous pregnancies that did not result in full-term delivery. The patient is presently 22 weeks pregnant.
• This patient is G6 P5. This one can be tricky because of the multiple gestation pregnancies (twins). Remember, even though there are multiple fetuses these only count as one event. 7 children with 2 sets of twins mean the patient was pregnant and gave birth 5 times. Factoring in the current pregnancy, the patient is Gravida 6, Para 5. 

Resources

1. Obstetric Words. n.d. Meditec. Retrieved from https://www.meditec.com/resourcestools/medical-words/obstetrics-words
2. Tidy C. Gravidity and Parity Definitions: Implications and Risk Assessment. Patient. Retrieved from https://patient.info/doctor/gravidity-and-parity-definitions-and-their-implications-in-risk-assessment
3. Mistry M. 2017. The Obstetric History. Teach me Bbgyn. Retrieved from https://teachmeobgyn.com/history-taking-examinations/history-taking/obstetric/
4. Grum T et al. 2017. Determinants of pre-eclampsia/Eclampsia among women attending delivery Services in Selected Public Hospitals of Addis Ababa, Ethiopia: a case control study. BMC Pregnancy and Childbirth. Retrieved from https://bmcpregnancychildbirth.biomedcentral.com/articles/10.1186/s12884-017-1507-1