Even if English is your first language, some of the terms used by medical staff during your pregnancy and labor can still be pretty confusing, right? That's why we asked Dr Nichole Mahnert, Ob/Gyn from our panel of experts, to come up with a list of common obstetric terms. It should help you decipher some of the terminology thrown around during your antenatal appointments, and ensure you are on the ball with any decisions that need to be taken during labor. If you think something is missing from the list, please let us know!
Common Obstetric Terms
- AC Abdominal circumference
An ultrasound measurement used to measure the diameter of the fetuses' abdomen, used in combination with other measurements to calculate the estimated fetal weight (EFW) or gestational age estimate (GA).
AFI Amniotic Fluid Index
A quantification of the amount of amniotic fluid
A test of the amniotic fluid to check for chromosomal abnormalities like Down's Syndrome.
Saline is infused through an IUPC into the uterus to help with variables seen on a fetal heart rate tracing, which corresponds to possible compression of the umbilical cord.
AROM Artificial ruptures of membranes
The doctor or midwife will use an 'amnio hook' to break the bag of water during a sterile vaginal examination
- BPD Biparietal Diameter
An ultrasound measurement taken between 14 and 20 weeks that measures the fetuses' head (intersects the third ventricle and the thalami) to estimate the gestational age.
- CI Cervical insufficiency
When your cervix dilates in the second trimester without feeling labor. This is not common.
CRL Crown Rump Length
The crown rump length is a measurement taken with ultrasound during the first trimester and measures from the top of the fetus head to its bottom. This measurement is used to estimate the gestational age (GA) and estimated due date (EDD).
CS Cesarean Section
A surgery performed to deliver the baby through surgery. The CS rate in China is nearly 50% and in the United States it ranges from 20 to 30%.
When the umbilical cord slips past the baby's head through the cervix, usually when the bag of water breaks. Very uncommon, but when it does it requires an emergency cesarean section.
A steroid injection given to a mom who is suspected may deliver preterm to help with baby's lung and organ development.
Measurement of how open the cervix is in centimeters from 0 to 10cm, which is completely dilation and means you are ready to push out a baby
- EDD Estimated Due Date
The estimated due date is calculated based on your last menstrual period (LMP) if it is accurate or based on the ultrasound measurements. The EDD is usually 40 weeks from the LMP. The ultrasound measurements for dating a pregnancy are more accurate earlier in the pregnancy, usually between 8 and 16 weeks. Remember that only 5% of babies are actually born on the 'due date'.
EFW Estimated Fetal Weight
Taking ultrasound measurements of the femur length (FL), abdominal circumference (AC) and head circumference (HC) can help to estimated the fetal weight.
ECV External Cephalic Version
A maneuver to help baby move from a breech to head down position.
Measurement of how thin the cervix is in a percentage from 0 to 100%, which means there is no cervix left. This percentage corresponds to the length of the cervix in centimeters where 0% is 4cm, 50% is 2cm and 100% is 0cm.
A small cut made at the bottom of the vagina to help the baby deliver faster. Usually only done if there are concerns the baby should be delivered more quickly. More common in China than in the United States.
- FL Femur length
An ultrasound measurement that measure the length of the femur (thigh bone) used to calculate the fetuses' estimated fetal weight (EFW) or gestational age estimate (GA).
FFN Fetal Fibronectin
A test performed during a speculum exam when a woman comes in with suspected pre term labor to help decide the risk for preterm delivery. Usually only performed between 24 and 34 weeks.
FHRT Fetal heart rate tracing
During labor the hospital will periodically check the heart rate of your baby, sometimes they require continuous monitoring.
FSE Fetal Scalp Electrode
A tool placed onto the baby's head to more accurately measure the heart rate.
FAVD Forcep Assisted Vaginal Delivery
An instrument used to place on the baby's head to help with vaginal delivery, often referred to as 'spoons'.
- GA Gestational Age
The age of the fetus usually calculated from the last menstrual period (LMP) or ultrasound measurements.
GBS Group B streptococcus
10 to 30% of women are naturally colonized with GBS in the vaginal canal. This test is usually performed at 36 weeks of gestation and if positive mom will be treated with Penicillin in labor. This is to prevent baby from acquiring GBS associated disease.
GTT Glucose Tolerance Test
Most women in pregnancy must take a glucose test between 24 and 28 weeks gestational age to screen for gestational diabetes. Usually you must drink sugary drink (50 grams) and check your blood sugar one hour later. If this is abnormal you will go on to do a 3-hour test (100 gram).
- HC Head circumference
An ultrasound measurement that measures the diameter of the fetuses' head used with other measurements to calculate the estimated fetal weight (EFW).
- IUPC Intrauterine Pressure Catheter
A long tube placed into the uterus through the cervix, past baby's head to measure the strength of contractions more precisely.
- LDR Labor and Delivery Room
A common position in which your feet and often your head are elevated above your hips, think stirrups.
LMP Last menstrual period
The first day of your last period.
The baby's first bowel movement, which can sometimes happen during labor in utero. Sometimes we are a little concerned if it is very thick.
- NT Nuchal Translucency
An ultrasound measurement that measures the thickness of the fetuses' neck, usually between 10 and 13 weeks gestational age. This measurement is often used in combination with other prenatal screening labs to determine the risk a fetus has for Down Syndrome.
- PPH Post Partum Hemorrhage
Significant blood loss following delivery.
PROM Premature Rupture of Membranes
When you break your bag of water and the contractions have not yet started
PPROM Preterm Premature Rupture of Membranes
When you break your bag of water and you are before 37 weeks of gestation
PPTL Post Partum Tubal Ligation
A procedure performed in the first day after a vaginal delivery made through a small incision near the belly button to cut the fallopian tubes to prevent future pregnancy.
PTL Preterm labor
Preterm labor is when you have contractions and your cervix dilates before 37 weeks of gestation
An injection of local anesthetic placed at the pudendal nerve, which is responsible for the perineum. It can relieve some discomfort, but not pressure. Think of it like when the dentist numbs your tooth.
The placenta is placed abnormally over or near the cervix. This usually requires a cesarean section for delivery.
A part of the placenta comes away from the attachment of the uterus.
- SCDs Sequential Compression Devices
Stockings put on your lower legs to help circulate the blood and prevent blood clots.
Measurement of where the bones of the baby's head lie in the birth canal in centimeters above or below the ischial spines (a bony structure of the pelvis). Documented as -3, -2, 0, +1, +2, +3 where greater than +3 is near crowning.
SROM Spontaneous rupture of membranes
When you naturally break your bag of water
SVD Spontaneous Vaginal Delivery
SVE Sterile Vaginal Exam
All vaginal exams in labor to check the dilation, effacement and station should be completed with sterile gloves to prevent infection. No betadine soap is needed.
- VAVD Vacuum Assisted Vaginal Delivery
A small suction cup is placed on the baby's head to help with vaginal delivery.
VBAC Vaginal Birth After Cesarean Section
Usually women who attempt a VBAC are monitored more closely because of the small increased risk of uterine rupture, which is when the uterus splits open, typically at the previous scar.