Many pregnant individuals wonder about cervical dilation as their due date approaches, especially around 38 weeks. Understanding these bodily changes can help alleviate common anxieties. This information provides clarity and reassurance about cervical checks and labor progression.
Understanding Cervical Changes
During late pregnancy, healthcare providers often assess several key changes in the cervix. One of these is cervical dilation, which measures how open the cervix has become, typically expressed in centimeters. A fully dilated cervix, ready for birth, measures 10 centimeters.
Another important measurement is effacement, which refers to the thinning and shortening of the cervix. The cervix, which is normally 3 to 5 centimeters thick, thins out to prepare for delivery, measured as a percentage from 0% (thick) to 100% (paper-thin). Along with dilation and effacement, providers also check the baby’s station, indicating the position of the baby’s head relative to the mother’s pelvis. This measurement, ranging from -5 to +5, helps assess how far the baby has descended into the birth canal.
The Reality at 38 Weeks
Many pregnant individuals wonder if they should be dilated at 38 weeks. There is significant variation in cervical dilation at this stage, and a wide range of findings are normal. Some may have a closed cervix (0 centimeters dilated), which is typical and does not indicate a problem. Others might be 1 to 2 centimeters dilated, or more, weeks before labor begins.
Being dilated several centimeters at 38 weeks also falls within the normal spectrum and does not necessarily mean labor is imminent. The cervix can open and thin gradually as the body prepares for birth, a process that can take days or weeks. Cervical dilation at 38 weeks is a poor predictor of when labor will start, as each individual’s timeline varies.
Beyond Dilation: Signs of Labor
While cervical dilation offers a snapshot of the body’s preparation, true signs of labor are more indicative of its onset. One primary indicator is the presence of regular, strong contractions that increase in intensity and frequency over time. These contractions do not subside with changes in activity or rest, and they often begin in the lower back, radiating to the abdomen. This distinguishes them from Braxton Hicks contractions, which are irregular, less intense, and may stop with movement.
Another sign is the rupture of membranes, commonly known as the “water breaking.” This can manifest as a sudden gush or a steady trickle of fluid. While a notable event, water breaking does not always immediately precede contractions. Loss of the mucus plug, which protected the cervix during pregnancy, is another potential sign, appearing as clear, pink, or bloody discharge. However, losing the mucus plug does not definitively signal immediate labor, as it can occur days or weeks beforehand.