The cervix is a muscular, tunnel-like structure connecting the uterus and vagina. It regulates the passage of fluids, notably during menstruation and childbirth.
The Cervix During Menstruation
During menstruation, the cervix softens and slightly opens. This allows menstrual blood and uterine tissue to pass from the uterus. While typically firm, it may feel softer to the touch.
This temporary change is influenced by hormone-like substances called prostaglandins. Produced in the uterine lining as progesterone levels decrease, prostaglandins trigger uterine contractions, helping shed its lining. These contractions, along with prostaglandins, cause the cervix to soften and slightly open, facilitating menstrual flow. This opening is very minimal compared to the dilation during childbirth.
Understanding Related Sensations
The changes in the cervix and uterus during menstruation can lead to various physical sensations. Many individuals experience menstrual cramps, which are throbbing or aching pains in the lower abdomen. These cramps are directly linked to the uterine contractions stimulated by prostaglandins. Higher levels of prostaglandins often correlate with more intense cramping.
Some people also describe a feeling of pressure or heaviness in the pelvic area, which can be associated with the uterus contracting and the cervix allowing passage of menstrual fluid. The intensity and type of sensation can vary significantly from person to person. While these sensations are a normal part of the menstrual process, particularly painful cramps, medically known as dysmenorrhea, can sometimes indicate an underlying condition.
Cervical Changes in Other Cycles
The cervix exhibits distinct changes throughout the entire menstrual cycle, not just during menstruation. For instance, around ovulation, the cervix typically becomes higher in the vagina, softer, and more open to facilitate the entry of sperm into the uterus. Cervical mucus also changes in consistency during this time, becoming clear, stretchy, and slippery, similar to raw egg whites, to aid sperm movement.
In stark contrast, during pregnancy, the cervix remains tightly closed and firm, forming a protective barrier and secreting a thick mucus plug to shield the developing fetus from infection. The most dramatic cervical change occurs during labor and childbirth. The cervix softens, shortens, and thins out, a process called effacement, and then dilates significantly, opening up to approximately 10 centimeters to allow the baby to pass through the birth canal. This extensive dilation is far greater than the slight opening observed during menstruation.