Vanishing twin syndrome, A rare cause of recurrent ante partum haemorrhage
S.Curpad, S. Chawathe
Prince Charles hospital, Merthyr Tydfil
To identify risk factors for this rare cause of ante partum haemorrhage.
Case report and Literature search
A 16 year Primigravida presented to the early pregnancy assessment unit at 5+3 weeks of
pregnancy with a history of painless bleeding per vaginum. Ultrasound examination revealed a
viable Dichorionic Diamniotic intrauterine pregnancy. However she presented again with bleeding
and a repeat ultrasound examination showed a Dichorionic Diamniotic pregnancy with two foetal
poles but with foetal heart beat demonstrable in one foetal pole only. Follow up scan did not
demonstrate second twin.
The patient presented with repeated admissions at 24,26,30, 34 and 39 weeks with uterine
contractions and bleeding per vaginum. On examination, there was no evidence of abruption, but
demonstrated regular uterine contractions and cervical os was closed.
CTG was normal with a single live intrauterine pregnancy and anterior placenta, normal growth,
liquor volume and umbilical artery Doppler's on ultrasound.
She was managed conservatively and was induced at 40+3 weeks. Manual removal undertaken for
retained placenta following vaginal delivery of live male baby showed a sac with haemorrhage
measuring 8 X 6 centimetres attached to the placenta. Histopathology revealed DCDA twin
placenta with blighted infracted foetus.
Vanishing twin syndrome, first described in 1945(1)
is the term used to describe multiple pregnancies
where one or more foetus will disappear as the pregnancy advances, seen in about 21-30% of multifetal
. The diagnosis has improved with increasing use of Ultrasound. Initial presentation is
similar to threatened miscarriage.
Pregnancy outcome and prognosis of the surviving twin depends on the gestational age at which the
foetal demise appears. The prognosis is excellent if the foetal demise is before 8 weeks gestation. The
foetus may be completely reabsorbed or may form a gelatinous sac. At later gestations may form foetus
papyruses or papery appearance due to absorption of the water and getting compressed between the
surviving foetus and the uterine wall. Cerebral palsy in surviving twin, preterm labour, abruptioplacentae may occur if foetal demise occurs at later gestation(3)
In the above case, the recurrent
bleeding into the sac of demised second twin caused recurrent ante partum haemorrhages. We were
unable to identify any report in literature suggesting the same.
Other complications include aplasia cutis in the surviving twin and an 3 fold increased incidence in
neonatal mortality of the surviving twin.
Vanishing twin syndrome is a rare occurrence however early identification may improve predicting
pregnancy outcome and prognosis.
•Vanishing Twin Syndrome Ann L Anderson-Berry David Chelmow
•Sampson A, de Crespigny LC. Vanishing twins: the frequency of spontaneous fetal reduction of a twin
pregnancy. Ultrasound Obstet Gynecol. Mar 1 1992;2(2):107-9.
•Landy HJ, Keith LG. The vanishing twin: a review. Hum Reprod Update. Mar-Apr 1998;4(2):177-83