Recurrent Miscarriage

Introduction

In about 2-5% of couples with a history of recurrent miscarriage, one partner carries a balanced chromosome rearrangement which confers an increased risk of miscarriage or live births with an unbalanced chromosome rearrangement. For couples ascertained following recurrent miscarriage, the risk of chromosomally unbalanced pregnancies surviving to term is low and therefore routine karyotyping of these couples is not indicated.

Referral information

From April 1st 2014, in accordance with the Royal College of Obstetricians and Gynaecologists guidelines, parental blood samples are no longer accepted from couples with isolated or recurrent pregnancy loss. Cytogenetic analysis may be performed on products of conception samples following the third and subsequent consecutive miscarriages or following the loss of a fetus with multiple structural abnormalities. Parental blood samples are accepted where: (1) testing of the products of conception sample shows an unbalanced structural fetal karyotype or (2) following the loss of a fetus with multiple congenital abnormalities or severe IUGR and material from the fetus or placenta is unavailable for cytogenetic testing.

Price & reporting times

Test Price (£ ex VAT) TRT *
Routine postnatal blood sample POA 28 cd
Fetal tissue or products of conception sample POA 28 cd

Test validation & quality assurance - information for users

Testing of fetal and products of conception samples may occasionally be complicated by maternal cell contamination.  In these cases, it may not be possible to issue a result. QF-PCR may not detect mosaicism or structural rearrangements. Microarray analysis will not detected balanced rearrangements and may not detect mosaicism. Microarray analysis may identify incidental findings unrelated to the cause of pregnancy loss. This laboratory participates in the CEQAS quality assessment scheme for this test.

Sample requirements

The most appropriate sample types are:

  • If possible, please send a sample of cardiac or cord blood in EDTA (0.5ml collected in a paediatric tube) or
  • A full depth skin sample (0.5cm³) or
  • A sample of umbilical cord tissue approximately 2-3 cm in length or
  • A sample of placental tissue approximately 1-2 cm3 in size which includes placental villi.

Please Note

  • Whole Fetuses cannot be accepted by the laboratory under any circumstances. The referring centre will be contacted to arrange collection.
  • Tissue samples that are more than 7 days post mortem or appear necrotic on arrival in the laboratory may not be suitable for cytogenetic testing. Please state the date of delivery on the referral form.
  • Samples that have been preserved in formalin are unsuitable for cytogenetic studies.
  • Please do not include cord clips, dressings or any other medical device with the sample.
  • Please do not send the entire products of conception from an early pregnancy loss. Please examine the tissue at delivery and only send sufficient material for testing (approx 1cm3).
  • Products of conception will only be accepted from clinically confirmed pregnancies (i.e. those that have been confirmed by both high levels of hCG and ultrasound confirmation of a gestational sac or fetal heartbeat). This information must be provided on the referral form.  Samples that do not meet these criteria cannot be processed.

Referral guidelines

Please see our referral guidelines for more information.

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