A cervical check, often performed in the later stages of pregnancy, is a brief vaginal exam used to assess the body’s readiness for labor or to monitor progress once contractions have begun. Typically offered weekly starting around 36 or 37 weeks, the provider uses this examination to feel for changes in the cervix and determine the baby’s position relative to the pelvis. Understanding the specific measurements taken can help demystify the process.
The Procedure and Purpose of a Cervical Check
The cervical check is a manual examination performed using two gloved, lubricated fingers inserted into the vagina to reach the cervix, the firm, muscular opening at the base of the uterus. The purpose is to assess several data points that, when taken together, inform delivery planning.
Before labor, the check is generally elective and establishes a baseline status. Once labor is underway, it is performed periodically to monitor the rate of progress toward delivery, focusing on changes in the cervix and the baby’s descent.
This exam helps determine if the body is beginning “cervical ripening” in preparation for birth. This data is particularly helpful for guiding labor induction methods. However, this check provides only a snapshot of the current status and does not accurately predict when labor will begin.
Fetal Station and Feeling the Baby’s Head
The ability to feel the baby’s head relates directly to “fetal station,” a measurement describing how far the presenting part (usually the head) has descended into the pelvis. This measurement compares the baby’s position to the ischial spines—two bony protrusions in the narrowest part of the pelvis.
The ischial spines are designated as the zero station, meaning the baby is “engaged” when level with this line. Measurements use a scale from -5 to +5, with each number representing a centimeter above or below the zero station. Negative numbers, such as -5, indicate the head is still high and not yet engaged.
If the baby is at zero station or a positive station, the provider can easily feel the presenting part during the internal exam. A positive number, such as +1 or +2, means the baby has descended past the ischial spines and is moving further down the birth canal. When the baby reaches +5, the head is typically visible at the vaginal opening, which is often referred to as crowning. The lower the station number, the lower the baby is positioned, signaling progress toward birth.
Measuring Cervical Dilation and Effacement
The cervical check assesses two other primary factors: dilation and effacement. Dilation refers to the opening of the cervix, measured in centimeters. The cervix must dilate from completely closed to 10 centimeters, which is full dilation and the point at which pushing begins.
Effacement is the measurement of the cervix’s thinning and shortening, expressed as a percentage. Before labor, the cervix is long and thick (about 2 to 3 centimeters, or 0% effaced). It thins out until it is 100% effaced, becoming very thin as the body prepares for birth.
The provider also assesses the cervix’s consistency (firm or soft) and position (pointed backward or moved forward). These factors, along with dilation and effacement, indicate how “ripe” the cervix is. For instance, a cervix that is soft, 50% effaced, and 2 centimeters dilated shows more readiness for labor than one that is closed and firm.
Managing Discomfort and Understanding Risks
Many people find the cervical check uncomfortable, describing the sensation as deep pressure or brief pain. Relaxing the pelvic floor muscles and using deep breathing techniques can help reduce discomfort during the procedure. Light spotting or minimal bleeding immediately afterward is common and normal, resulting from the cervix being touched.
The check carries a risk of stimulating contractions or accidentally rupturing the amniotic sac, especially if performed with a membrane sweep. Frequent cervical exams, particularly after the water has broken, can increase the risk of infection, such as chorioamnionitis. Routine cervical checks before labor are elective, and patients have the right to decline the procedure at any time.