Page 161 - كتاب تمريض نسا الاكتروني

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Summary In Study Session 1A&B, you have learned that:

1. The bony pelvis is composed of the ilium, ischium, pubic bones and sacrum.

2. The size and shape of the bony pelvis can affect the ease or difficulty of labor and
delivery; a broad pelvis gives less difficulty than a narrow one, which may obstruct the
descent of the fetus down the birth canal.

3. Certain landmarks in the anatomy of the pelvis are commonly used to estimate the
descent of the fetus during labor and delivery. The two most important landmarks are
the ischial spines and the sacral promontory, which can be felt with the fingers during
a vaginal examination.

4. The pelvic inlet is the space where the fetal head enters the pelvis; it is larger than
the pelvic outlet, where the fetal head emerges from the pelvis. In order to get through
the widest diameter of the inlet and the outlet, the fetus has to rotate as it passes through
the pelvic canal.

5. The skull is formed by several bones joined tightly together by joints called sutures.
In the fetus and newborn, spaces called fontanels exist between some of the skull bones
on the top of the fetal head. The position of the sutures and the fontanels can tell you
about the angle at which the fetal head is presenting during labor and delivery.

6. The vertex presentation (where the top of the fetal head is the presenting part) is the
most common and the safest presentation for a normal vaginal delivery. Other
presentations carry a much higher risk for the mother and fetus.

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