mcdonald and shirodkar/cervical incompetence/CERVIX length measurement

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mcdonald and shirodkar

cervical incompetence

 

The cervix normally remains tightly closed until the
time of delivery. Dilatation of the cervix before term can

lead to second trimester spontaneous abortion or premature
delivery. Cervical incompetence is the painless cervical
dilatation. Placement of a stitch, known as a cerclage
loop, prevents further dilatation and permits the pregnancy
to continue. 

CERVIX length measurement

CERVIX length measurement

cervix length (A)

  funneling +

  funnel width (C)

  funnel length (B)

Yellow dot (cerclage)

 

Several sonographic criteria have been
proposed for early detection of cervical incompetence.
Opening of the internal os with or without observance of
protruding or herniating membranes, or a cervical length
less than 2.5 centimeters (cm) in the third trimester is
suggestive of cervical incompetence. 1,4 Once a cerclage
is in place, it is visible sonographically as several bright
echoes within the muscle of the cervix 

 
Marked dilatation of the cervix with bulging of membranes
through the external os is a poor prognostic sign.

Take special care while imaging the contents of the fl uid
and membranes protruding into the cervical canal.

The presence of any part of the umbilical cord within the
cervical canal is a serious threat to the fetus, an obstetric
emergency requiring immediate intervention .