Glossary of Pregnancy Terms

Below you will find a glossary of the most common terms related to pregnancy. The definitions will aid in helping to understand the treatment that our doctors, midwives and nurses provide.

Amniotic Sac
The thin membrane which encloses the baby and the amniotic fluid. At full term, there is roughly a quart of amniotic fluid surrounding the baby. About one third of this fluid is constantly being replenished every hour.

Artificial Rupture of Membranes (AROM)
The physician breaks the bag of water in order to: 1) Visualize the color of amniotic fluid before birth, or 2) As a means of helping increase the frequency and/or strengthen the uterine contractions.

Braxton-Hicks
Usually painless uterine contractions which the mother may feel from about the fifth month on. Less than four per hour is considered normal. Walking increases the intensity and resting usually decreases the intensity.

Colostrum
The first milk produced by mom. It is higher in protein than mature breast milk and contains immune properties (passive immunity) which protect the infant from infections.

Crowning
The baby's head is visible as mom pushes. Crowning usually denotes that the head is still visible even in between pushes.

Dilation
The opening up of the cervix. Measured in centimeters.

EDD
Estimated date of delivery or "due date".

Effacement
The thinning and shortening of the cervix. Measurement of effacement is described in terms of percentages.

Engagement
When the baby's head is far enough into the bony pelvis that it no longer can move back up, or float freely in the amniotic fluid.

Engorgement
On about day three postpartum, sometimes the breasts become hard and swollen (engorged) as the milk comes in.

Fetal Heart Tones (FHT)
The baby's heartbeat. Normal range is 120 to 160 beats per minute.

Involution
The process of the shrinking of the uterus to its pre-pregnant size. This process takes approximately six weeks.

Lightening
The sensation the mother feels when the baby "drops" down or gradually settles into the pelvis.

Lochia
Discharge of blood, mucus and tissue from the placental implantation site and the uterus after the birth of a baby. May continue several weeks and vary in amount. Begins red, gradually clearing to colorless serum.

Mucus Plug
A plug of heavy mucus which blocks the opening of the cervix to prevent bacteria from entering the uterus. Before labor, this mucus plug is expelled so that the cervix can open to allow the baby to pass through during labor and birth.

Multigravida
A woman pregnant with her second or subsequent child.

Multipara (multip)
A woman who has given birth to her second or subsequent child.

Perineum
The skin and muscles which surround the urethra (the opening to the bladder), the vagina, and the anus.

Placenta
The vascular structure developed in pregnancy through which nutrition and excretion takes place between mother and baby.

Preeclampsia
A rapidly progressive condition characterized by high blood pressure and the presence of protein in the urine. Swelling, sudden weight gain, headaches and changes in vision are important symptoms.

Preterm Labor
More than four uterine contractions in an hour before 36 weeks of pregnancy. The true definition of Preterm labor is cervical change.

Primigavida
A woman pregnant with her first child.

Primipara (primip)
A woman who has given birth to her first child.

Spontaneous Rupture of Membranes (SROM)
If this occurs long before labor onset, it is called PROM (premature rupture of membranes). Usually labor naturally begins within a few hours (if it already hasn't) after SROM.

Station
The relationship between the baby's head to the bony pelvis of the mom. It measures how deep into the pelvis the baby is dipping.

True Labor
Unlike Braxton-Hicks contractions, true labor contractions usually come in a regular pattern, gradually get closer together and gradually increase in intensity. True labor results in the effacement and dilation of the cervix and the eventual expulsion of the baby.

Uterus
Muscular organ of gestation; consists of a pear-shaped fundus which is the top or uppermost portion, and a narrower lower portion called the cervix. The cervix resembles a "neck" until the time of birth when it opens into the birth canal (or vagina) to allow passage of the baby. The cervical os (or opening) is the portion of the cervix which is measured during dilation.