Update information

Update information

April 2024: We have reviewed the evidence and made new and updated recommendations, and a recommendation for research, on interventions to prevent spontaneous preterm birth and progesterone for preventing spontaneous preterm birth in twin and triplet pregnancy. These recommendations are marked [2019, amended 2024] or [2024].

September 2019: We have reviewed the evidence and made new recommendations on fetal complications, preterm birth, timing of birth and intrapartum care. These recommendations are marked [2019].

We have also made some changes without an evidence review:

  • Amnionicity was added to relevant recommendations in section 1.1 (and recommendation 1.4.2) in addition to chorionicity because monoamnionicity is an additional complication that would need to be determined to inform management.

  • 'Down's syndrome' has been removed from recommendation 1.1.1 because screening for chromosomal conditions is covered in a separate section.

  • The approximate timing of the first trimester ultrasound scan has been updated in line with NHS fetal anomaly screening programme (FASP) recommendations in recommendations 1.3.7, 1.3.8, 1.3.9, 1.3.10 and 1.4.5.

  • 'The presence of amniotic membrane(s)' was added to recommendations 1.1.3 and 1.1.5 because the number as well as thickness of membranes needs to be determined.

  • 'Antenatal' was added to recommendation 1.3.1 to distinguish this recommendation from the new intrapartum care section that was added in this update. The whole team providing antenatal care would not be needed or relevant for intrapartum care.

  • Two additional scans and appointments were added to recommendations 1.3.8 and 1.3.9 (at 26 and 30 weeks) because of new recommendations on increased screening and monitoring.

  • The types of pregnancy covered by recommendation 1.3.10 are usually complicated so 'uncomplicated' was removed. The number of appointments with the specialist obstetrician was also changed from 2 to 5 because more frequent review is needed: monochorionic triamniotic triplet pregnancies are very rare and have a higher potential for adverse outcomes from complications of monochorionicity than monochorionic twins.

  • In the section on 'screening for chromosomal conditions':

    • Edwards' syndrome and Patau's syndrome were added to Down's syndrome because since 2011 there is now a combined test for all of them.

    • Twin pregnancies have been removed from recommendations in this section because they are covered by the NHS fetal anomaly screening programme (FASP).

  • Recommendation 1.6.2 now simply cross-refers to the hypertension in pregnancy guideline.

  • Recommendation 1.7.1 was updated to reflect changes in the fetal growth restriction section as well as the addition of suspected twin anaemia polycythaemia sequence (TAPS) to the guideline. Twin reverse arterial perfusion sequence (TRAP) and conjoined twins or triplets were added because they would always need consultant opinion from a tertiary level fetal medicine centre.

These recommendations are marked [2011, amended 2019].

Recommendations marked [2011] last had an evidence review in 2011. In some cases minor changes have been made to the wording to bring the language and style up to date, without changing the meaning.

Minor changes since publication

October 2023: We updated links to the NICE guideline on intrapartum care, which has been updated.

December 2022: We updated the links in recommendation 1.11.9 to refer to the NICE guideline on fetal monitoring in labour.

November 2022: We added '× 100' to the formula for calculating estimated fetal weight discordance in twins and triplets to give the result as a percentage. See recommendations 1.4.20, 1.4.21 and 1.4.33.

December 2019: We updated the name of the Twins and Multiple Births Association to Twins Trust.

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