Page 42 - 2023 Elctronic Book (3) Normal Labor_Neat

There are symptoms and signs, which may occur in the last week or days of pregnancy
before the actual onset of labor and include:

1-Shelving:
The fundus of the uterus descends slightly &falls forwards; it brings the fetus in the
direction of the axis of the pelvis.

2- Lightening “after engagement”:
o It is the sinking of the uterus that is observed by descent of the

abdomen. This alteration is brought by engagement, which means
setting of the fetal head into the true pelvis.
o In prime gravidas, lightening usually occurs 2-3 weeks before labor.

o In multiparas, it is more likely to occur after labor begins and even
after the start of the second stage.
o Relief of upper abdominal pressure symptoms (dyspnea Dyspepsia,

palpitation) due
to descent of the uterine fundus &due to shelving.
o Signs of greater lower pressure follow this relief such as shooting

pains in the leg due to pressure on the sciatic nerve and an increase of
the vaginal discharge.

3-Frequency of micturition:
It occurs as a result of engagement. The pressure of the presenting part on the urinary
bladder limits its capacity.
4-Effacement of the cervix:

Is the shortening or slight taking up of the cervical canal from structure of
approximately 2 cm in length to 1 cm

 Relationship of Maternal Pelvis and Presenting Part:

 Engagement of the presenting part occurs when the largest diameter of the

presenting part reaches or passes through the pelvic inlet. Engagement can

be determined by vaginal examination. In Primigravida engagement

usually occurs 2 weeks before term. However, multiparas may experience

engagement several weeks before the onset of labor during the process of

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