Correct Answer: D. G2P1
Gravida (G) counts the total number of pregnancies (including current), while para (P) counts the number of deliveries after 20 weeks of gestation (viable pregnancies), regardless of fetal outcome. This patient has two pregnancies: (1) the twin delivery 4 years ago, and (2) the current pregnancy at 38 weeks. Therefore, she is G2 (gravida 2). For parity, a twin delivery counts as ONE para because it is a single pregnancy event resulting in delivery after 20 weeks, even though two infants were delivered. The current pregnancy has not yet delivered, so it does not contribute to parity. Thus, her parity is P1 (one delivery after 20 weeks). The correct answer is G2P1. This distinction is critical in Indian obstetric practice where twin pregnancies are increasingly common and must be correctly classified for risk stratification and management protocols.
Why the other options are wrong
A. G3P2 — This incorrectly counts the twin delivery as two separate para events (P2) instead of one. A twin pregnancy is a single pregnancy event; delivery of twins counts as one para, not two. Additionally, it counts gravida as 3, which would only be correct if there were three separate pregnancies—but the patient has only two (the twin pregnancy and the current one). B. G3P1 — This correctly identifies parity as P1 (one delivery after 20 weeks from the twin pregnancy), but incorrectly counts gravida as 3. The patient has only two pregnancies: the past twin pregnancy and the current pregnancy at 38 weeks. Gravida should be 2, not 3. This is a common trap where students confuse the number of infants delivered with the number of pregnancies. C. G2P2 — This correctly identifies gravida as 2 (two pregnancies), but incorrectly counts parity as P2. The twin delivery is a single pregnancy event and therefore counts as one para, not two. Confusing the number of infants born with the number of parity events is a frequent error in obstetric scoring, especially in multiple gestations.
High-Yield Facts
- Gravida (G) = total number of pregnancies including the current one; a twin pregnancy counts as ONE gravida.
- Para (P) = number of deliveries after 20 weeks of gestation (viable pregnancies); twin delivery = one para, not two.
- Multiple gestations (twins, triplets) count as a single pregnancy event for both gravida and para scoring, regardless of number of infants.
- Current pregnancy at 38 weeks has NOT delivered yet, so it does not contribute to parity until after delivery.
- In Indian obstetric practice, correct G/P scoring is essential for risk assessment, especially in high-risk populations with higher twin pregnancy rates.
Mnemonics
G = Gestations (all), P = Pregnancies (past, delivered) Gravida counts every pregnancy (including current). Para counts only completed pregnancies (after 20 weeks). Twins = 1 pregnancy event = 1 para. One Pregnancy Event = One Para (even if multiple babies) Whether singleton or triplets, if delivered together after 20 weeks, it's ONE para. Don't count babies; count delivery events.
NBE Trap
NBE commonly pairs multiple gestations with parity scoring to trap students who count the number of infants delivered rather than the number of pregnancy/delivery events. The distractor G3P2 exploits this by suggesting twins = 2 para.
Clinical Pearl
In Indian antenatal clinics, correct G/P scoring is vital for risk stratification—a multiparous woman (P ≥ 2) has different obstetric risks (uterine atony, PPH) than a primigravida. Misclassifying a twin-delivery mother as P2 instead of P1 can lead to incorrect risk assessment and suboptimal counseling.
_Reference: DC Dutta's Textbook of Obstetrics, Ch. 1 (Obstetric History and Examination); OP Ghai's Essential Obstetrics, Ch. 2 (Obstetric Terminology and Definitions)_