The aspect of uterine cervix plays a key role during pregnancy and during labor. During pregnancy the uterine cervix needs to be firm as the uterus enlarges and during delivery the cervix needs to soften to allow the birth of the infant and this procedure of softening of the uterine cervix is termed as cervical ripening. In fact it is necessary for the cervix to soften in order to promote cervical dilation and a normal delivery of the fetus. During pregnancy the normal cervix measures to 3.5 cm and is mostly composed of connective tissues known as collagen.
Cervical ripening is known to commence prior to the labor contractions. Cervical ripening is in fact necessary for the process of cervical dilation and also the fetus to pass through the birth canal. In fact cervical ripening is known to occur as a result of several composite biochemical processes ending with molecular alignment of the collagen. During labor the cervix is known to become thin and soft as it opens up to respond to the contractions in the uterine.
During late pregnancy the content of hyaluronic acid in the cervix increases. This mostly tends to lead to an increase in the level of water molecules which tends to intercalate among the fibers of collagen. The other changing factors are decreasing dermatan sulfate, a decrease in firmness of the cervix and decreasing of Chondroitin sulfate. In fact cervical ripening is known to be strictly associated with the aspects of decreasing of alignment of collagen fiber, decreased strength of collagen fiber, and decrease in tensile strength of extracellular cervical matrix.
In short cervical ripening results from collagen realignment. Due to proteolytic enzymes there is degradation in collagen cross linking and lastly there is dilation which results from uterine contractions. The series of events signifying the aspect of cervical ripening tend to occur either simultaneously or in a proper sequence.
The various hormones responsible for causing the cervical ripening are prostaglandin E2, Prostaglandin F2-alpha, matrix metalloproteinases 2 and 9. An increase in the level of enzyme cyclooxygenase-2 leads to an increase in prostaglandin E2.
The changes occurring in the body due to increase in prostaglandin E2 are dilation of cervical vessels which are small, collagen degradation increment, hyaluronic acid increment, chemotaxis increase causing increased degradation of collagen and lastly there is increased interleukin stimulation. Cervical ripening is also known to be associated with the increase in activity of the matrix metalloproteinases 2 and 9 which are the enzymes degrading the extracellular matrix proteins.
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There are a variety of ways for quantification of cervical ripening to predict the proper labor and delivery time. Bishop score being one of the methods keeps a track of cervical dilatation, consistency, position, effacement, and the base of the presenting part.
To know more about the Types of Childbirth and Labor browse through the pages of pregnancyxl.com.
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