The cervix is about an inch long but can vary in length and width during a woman’s lifetime.
The cervix contains:
you’re free to locate the external cervical os during a simpleself-exam.
During ovulation, the cervix is high and positioned closer to the top of the vagina.
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This change of position allows the cervical os to open more readily to allow sperm to enter.
The mucus becomes thinner and clearer to ensure the sperm can make their way to the cervical os.
During the non-fertile stage of menstruation, the cervix is low and firm and the cervical os closes.
Vaginal secretions become thicker and more acidic to protect against bacteria and other infectious agents.
This change is in response to both the stage of pregnancy and the growth of the developing fetus.
The cervix provides stable support for the babys head at this stage.
The baby is usually in a head-first position toward the cervical canal.
As it becomes wider, the cervix also becomes shorter and thinner, a phenomenon known as effacement.
In the process of effacement, the internal and external os come closer together.
During the second stage, the cervix opens to the full dilation of 4 inches (10 centimeters).
This is when the mother begins actively pushing to deliver the baby through the birth canal.
What Is a Closed Cervix?
In some cases, the cervical os will get abnormally narrow or close completely.
This is a condition known as cervical stenosis.It is possible to be born with a closed cervix.
It can also be a result of uterine surgery,endometriosis, scarring, cysts, or cervical cancer.
Symptoms can include periods that become more irregular or painful.
A closed cervix can also cause infertility because sperm cant travel into the uterus to fertilize an egg.
To diagnose a closed cervix, your gynecologist needs to perform a pelvic examination to see your cervix.
If they cant, you may get a diagnosis of cervical stenosis.
Summary
The cervical os is the opening in the cervix at each end of the endocervical canal.
The external os is near the vagina, and the internal os is near the uterus.
During your menstrual cycle, the cervical os opens more readily during ovulation to allow sperm to enter.
A condition called cervical stenosis, or closed cervix, can cause painful periods.
It may also cause infertility because the sperm can’t reach the egg.
To correct this, a cervical dilator can help to kick off the cervix slowly over time.
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