Pregnancy Abbreviations, Terms, and Stages - Definitions, Pregnancy duration and Classification of pregnancy stages

Pregnancy is a fascinating and complex journey, not only for the mother and family but also for healthcare professionals who play a critical role in ensuring safe outcomes. Medical students, nurses, and practitioners often come across a wide range of pregnancy-related abbreviations, terms, and classifications that are essential for communication, diagnosis, and treatment. At the same time, expecting parents may encounter these terms in medical records, ultrasound reports, or hospital discussions.

Pregnancy Abbreviations and Their Meanings

Medical abbreviations make communication faster, but for beginners, they can be overwhelming. Below is a detailed explanation of the abbreviations most commonly used in obstetrics and gynecology (OB-GYN).

Abbreviations for Pregnancy Status and Outcomes

IUP/IUFD – Intrauterine pregnancy / Intrauterine fetal demise (pregnancy inside the uterus / fetal death inside uterus)

SAB – Spontaneous abortion (miscarriage without medical intervention)

TAB – Therapeutic abortion (planned termination for medical or personal reasons)

LMP – Last menstrual period (basis for calculating gestational age)

ROM / SROM – Rupture of membranes / Spontaneous rupture of membranes (breaking of water naturally)

AROM – Artificial rupture of membranes (done by healthcare provider)

PROM / PPROM – Prolonged rupture of membranes (>24 hours) / Preterm premature rupture of membranes

Abbreviations for Delivery

SVD – Spontaneous vaginal delivery

VBAC – Vaginal birth after cesarean

Abbreviations Related to Fetal Monitoring

FHR – Fetal heart rate

EFM – Electronic fetal monitoring

US – Ultrasound (used to detect FHR and fetal growth)

FSE – Fetal scalp electrode (for accurate heart rate reading)

IUPC – Intrauterine pressure catheter (measures contraction strength)

LTV – Long-term variability (variation in FHR pattern)

Abbreviations for Labor and Prenatal Care

NST – Non-stress test (fetal well-being test)

CST – Contraction stress test

BPP – Biophysical profile (ultrasound-based fetal well-being test)

AFI – Amniotic fluid index

PTL – Preterm labor

NP/NP Care – No prenatal care / Late prenatal care

Abbreviations for Obstetric Procedures

BTL – Bilateral tubal ligation (permanent contraception)

D&C / D&E – Dilation & curettage / Dilation & evacuation (uterine evacuation procedures)

Abbreviations for Infant Outcomes

BOA – Born on arrival (baby delivered before hospital arrival)

VMI / VFI – Viable male infant / Viable female infant

BUFA – Baby up for adoption

Abbreviations for Estimated Dates

EDD / EDC / EDB – Estimated date of delivery / confinement / birth

Pregnancy Duration: Gestational Age vs. Fetal Age

Understanding pregnancy duration is vital for both clinical practice and parental awareness.

Gestational Age (40 weeks) – The time calculated from the first day of the last menstrual cycle (LMP). It includes the two weeks before actual conception.

Fetal Age (38 weeks) – The true developmental age of the baby, calculated from the date of conception, usually two weeks shorter than gestational age.

This distinction is important because most medical records, ultrasound reports, and pregnancy tracking apps use gestational age, not fetal age.

Trimesters of Pregnancy

Pregnancy is divided into three trimesters based on gestational age.

Trimester	Weeks Covered	Key Features
First Trimester	0 – 13 weeks	Major organ formation, early symptoms like nausea and fatigue
Second Trimester	14 – 26 weeks	Fetal growth, mother feels baby movement (quickening)
Third Trimester	27 – 40 weeks	Final growth, organ maturity, preparation for birth

Prenatal Terms Explained

Gravida (Gravidity)

Refers to the number of times a woman has been pregnant, regardless of outcome.

Nulligravida – Never been pregnant

Primigravida – Pregnant for the first time

Multigravida – Pregnant two or more times

Parity

The number of pregnancies that have reached viability (≥20 weeks of gestation), regardless of whether the baby was born alive or stillborn.

Nullipara – Zero pregnancies beyond viability

Primipara – One pregnancy reaching viability

Multipara – Two or more pregnancies reaching viability

Classification of Pregnancy by Duration

Pregnancy is further classified into preterm, term, and post-term based on duration.

Category	Definition	Duration
Preterm	Pregnancy ending after 20 weeks but before 37 weeks	< 37 weeks
Early Term	Pregnancy reaching 37 – 38 ⁶/₇ weeks	37 – 38 ⁶/₇
Full Term	Pregnancy between 39 – 40 ⁶/₇ weeks	39 – 40 ⁶/₇
Late Term	Pregnancy lasting 41 – 41 ⁶/₇ weeks	41 – 41 ⁶/₇
Post-term (Postdate)	Pregnancy going beyond 42 weeks	> 42 weeks

Practical Quick Reference Table

Term	Meaning
LMP	Last menstrual period
EDD	Estimated date of delivery
SVD	Spontaneous vaginal delivery
VBAC	Vaginal birth after cesarean
PTL	Preterm labor
PROM	Prolonged rupture of membranes
Nulligravida	Never been pregnant
Primigravida	Pregnant for the first time
Multipara	Two or more pregnancies reaching viability

FAQs on Pregnancy Abbreviations and Terms

Q1. What is the difference between Gravida and Parity?

Gravida counts all pregnancies, including miscarriages and abortions, while Parity counts only pregnancies that reached 20 weeks or more.

Q2. Why is gestational age two weeks longer than fetal age?

Because gestational age starts from the first day of the last menstrual period, not from the date of conception.

Q3. What does Preterm mean in pregnancy?

Preterm refers to a baby born after 20 weeks but before 37 weeks of pregnancy.

Q4. What is considered Full Term pregnancy?

A pregnancy between 39 and 40 ⁶/₇ weeks is considered full term, which is ideal for healthy birth outcomes.

Q5. What does VBAC stand for and when is it possible?

VBAC means Vaginal Birth After Cesarean. It is possible if the mother had a previous cesarean but meets safety criteria for vaginal delivery.