USG sign of fetal death:a) Halo' sign of headb) Heart beat absentc) Spalding signd) Hegar's sign
Intrauterine fetal death is death of the fetus in utero after the period of viability (after 22 weeks) or when fetus weighs more than 500 gm.

IUD can be diagnosed clinically by:

The size of the uterus less than the period of gestation.
Liquor decreased.
FHS absent.
Fetal movements abscent.
Egg-shell crackling feel of the fetal head (late feature).

Ultrasound: Earliest diagnosis is possible by USG.
Diagnostic features:

Absence of fetal cardiac activity on ultrasound scan (diagnostic).
Decreased liquor amnii.
Spalding’s sign i.e., overlapping of fetal skull bones due to shrinkage of cerebrum after fetal death. (see color plate given at the end for spalding sign).

Radiology:

Roberts sign: Presence of gas in the fetal large vessels(earliest sign-seen 12 hours after fetal death).
Ball sign: Crumpled up spine of the fetus or hyperflexion of the spine.
Spalding’s sign: Overlapping of fetal skull bones seen due to shrinkage of cerebrum after death of fetus. Crowding of the ribs shadow with loss of normal parallelism.
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c
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bc