Key priorities for implementation

Key priorities for implementation

The following recommendations have been identified as priorities for implementation.

Determining gestational age and chorionicity

  • Offer women with twin and triplet pregnancies a first trimester ultrasound scan when crown–rump length measures from 45 mm to 84 mm (at approximately 11 weeks 0 days to 13 weeks 6 days) to estimate gestational age, determine chorionicity and screen for Down's syndrome (ideally, these should all be performed at the same scan)[1].

  • Determine chorionicity at the time of detecting twin and triplet pregnancies by ultrasound using the number of placental masses, the lambda or T-sign and membrane thickness.

  • Assign nomenclature to babies (for example, upper and lower, or left and right) in twin and triplet pregnancies and document this clearly in the woman's notes to ensure consistency throughout pregnancy.

  • Networks should agree care pathways for managing all twin and triplet pregnancies to ensure that each woman has a care plan in place that is appropriate for the chorionicity of her pregnancy.

Specialist care

  • Clinical care for women with twin and triplet pregnancies should be provided by a nominated multidisciplinary team consisting of:

    • a core team of named specialist obstetricians, specialist midwives and ultrasonographers, all of whom have experience and knowledge of managing twin and triplet pregnancies

    • an enhanced team for referrals, which should include:

      • a perinatal mental health professional

      • a women's health physiotherapist

      • an infant feeding specialist

      • a dietitian.

        Members of the enhanced team should have experience and knowledge relevant to twin and triplet pregnancies.

  • Coordinate clinical care for women with twin and triplet pregnancies to:

    • minimise the number of hospital visits

    • provide care as close to the woman's home as possible

    • provide continuity of care within and between hospitals and the community.

  • The core team should offer information and emotional support specific to twin and triplet pregnancies at their first contact with the woman and provide ongoing opportunities for further discussion and advice including:

    • antenatal and postnatal mental health and wellbeing

    • antenatal nutrition

    • the risks, symptoms and signs of preterm labour and the potential need for corticosteroids for fetal lung maturation

    • likely timing and possible modes of delivery[2]

    • breastfeeding

    • parenting.

Monitoring for intrauterine growth restriction

  • Estimate fetal weight discordance using two or more biometric parameters at each ultrasound scan from 20 weeks. Aim to undertake scans at intervals of less than 28 days. Consider a 25% or greater difference in size between twins or triplets as a clinically important indicator of intrauterine growth restriction and offer referral to a tertiary level fetal medicine centre.

Indications for referral to a tertiary level fetal medicine centre

  • Seek a consultant opinion from a tertiary level fetal medicine centre for:

    • monochorionic monoamniotic twin pregnancies

    • monochorionic monoamniotic triplet pregnancies

    • monochorionic diamniotic triplet pregnancies

    • dichorionic diamniotic triplet pregnancies

    • pregnancies complicated by any of the following:

      • discordant fetal growth

      • fetal anomaly

      • discordant fetal death

      • feto-fetal transfusion syndrome.

Timing of birth

  • Offer women with uncomplicated:

    • monochorionic twin pregnancies elective birth[2] from 36 weeks 0 days, after a course of antenatal corticosteroids has been offered

    • dichorionic twin pregnancies elective birth[2] from 37 weeks 0 days

    • triplet pregnancies elective birth[2]from 35 weeks 0 days, after a course of antenatal corticosteroids has been offered.

[1] 'Antenatal care' (NICE clinical guideline 62) recommends determination of gestational age from 10 weeks 0 days. However, the aim in this recommendation is to keep to a minimum the number of scan appointments that women need to attend within a short time, especially if it is already known that a woman has a twin or triplet pregnancy.

[2] Specific recommendations about mode of delivery are outside the scope of this guideline.

  • National Institute for Health and Care Excellence (NICE)