Remarks

• The evidence on effects of routine imaging ultrasound before 24 weeks of pregnancy has not changed materially since the 2016 recommendation. A newly identified large-cluster randomized controlled trial (RCT) conducted in low-resource settings was reviewed but was not found suitable for inclusion in metaanalysis, because it evaluated the effect of two imaging ultrasounds conducted in both the second and third trimesters (i.e. it did not address the guideline’s participants, intervention, comparator, outcome [PICO] question).
• Implementation considerations associated with this recommendation have been significantly expanded based on the findings of a new qualitative evidence synthesis of the views and experiences of service users and health workers.
• Ultrasound scan can guide subsequent care. When implementing or scaling up routine imaging ultrasound before 24 weeks of pregnancy, the purpose of imaging ultrasound should be to assess:
• location of pregnancy (e.g. intrauterine)
• cardiac activity
• fetal size
• gestational age
• fetal number
• chorionicity and amnionicity for multiple gestation.
• Where the skill set and health systems allow, the following, which are more informative after 18 weeks of pregnancy, may also be assessed:
• presence of normal head, neck, face, spine, chest, heart, abdomen, abdominal wall and extremities
• placental appearance and location, and umbilical cord.
• Those who perform obstetric ultrasound should have specialized training that is appropriate to the practice of screening ultrasound in pregnancy.
• Many pregnancy complications, including fetal malformations, may develop later in pregnancy or may not be detectable without appropriate ultrasound training and equipment.
• There remain some uncertainties around undesirable effects, including the risk of litigation, the potential for female feticide, the short- and long-term psychological impact of an inconclusive or adverse scan finding, and the potential for overuse of ultrasound scans (as a replacement for formal ANC contacts).

Implementation considerations General considerations n When implementing ultrasound use, policy-makers should consider the financial implications of: creating/ updating national policies and standards for ultrasound use, including which cadres will perform it; standardized training of relevant health personnel (initial and refresher); extra personnel; understanding power supply and availability (including surge protection and environmental upgrades); infection control supplies and processes; providing routine maintenance and repair; replacing trained staff lost through attrition; and monitoring and evaluation for quality assurance. n Policy-makers should be aware of the potential for overuse of ultrasound and restrict the number to that recommended according to the woman’s condition. n Policy-makers and health system managers should work with front-line health workers to design systems that allow gestational age information derived from ultrasound to be available in all settings where women (especially those in preterm labour) may present for care, thus facilitating clinical decision-making that considers the most appropriate interventions and setting for birth, given estimated gestational age. n Policy-makers need to consider the diversion of resources from other health-care needs. Also, and in countries where maternal and perinatal mortality is very high, priority may be given to interventions that improve survival. Use of ultrasound equipment for non-obstetric purposes should also be reflected when calculating overall costs. n Policy-makers should also consider health worker/facility capacity for consultations and referral upon suspicion or detection of complications. n Functional obstetrical ultrasound programmes include strong systems to ensure safe management of conditions requiring urgent intervention (e.g. extrauterine pregnancy, placenta praevia, placenta accreta spectrum). Logistical considerations n Extra space and seating may be required to facilitate women bringing partners and other family members to ultrasound scans. n Ideally, the room (or environment) where the scan and related counselling take place should be in a private location, away from the waiting room, to ensure privacy and confidentiality. Addressing privacy, comfort and needs of women is important. Where possible, sonographers should ensure that women (and their partners) can see the image on the screen when discussing fetal well-being. n In some locations (e.g. isolated or rural areas), portable ultrasound equipment may be useful, especially in communities that may not have the resources to engage with formal maternity services or where poor infrastructure limits access. These settings are often poorly equipped to charge and protect devices – which needs to be considered, as well as building capacity to consult via phone, etc. In addition, it is important to ensure that the portable ultrasound equipment is of adequate quality for the task. n While new devices may increase accessibility, some may require: additional viewing devices, such as a compatible phone or tablet; the downloading of specific applications (apps), which may be subject to regulatory constraints; recharging (for rechargeable devices); connectivity to built-in consultation functionality; and device security. n Expanding the scope of practice for health workers can have both positive and negative consequences. While the opportunity to acquire new skills such as for ultrasound scans may be welcome and rewarding for some health workers, others may find new requirements burdensome and/or distracting from their current duties. Policy-makers should also be mindful of the potential negative impact of shifting skilled birth attendants to performing scans in settings with shortages. Training and education considerations n Policy-makers at national and local levels should promote evidence-based standards and training for health workers (physicians, nurses, midwives and sonographers). Health workers should have had comprehensive training on the use and maintenance of equipment, on how to perform standard components of ultrasound screening, how to record and counsel women regarding results, and how to manage any abnormalities diagnosed by ultrasound. n Health workers should make women aware of the availability of ultrasound, its purpose, benefits and limitations, and potential out-of-pocket costs. n In settings where the availability or supply of sonographers is limited, policy-makers could consider training other cadres (e.g. midwives, obstetricians or nurses) to perform antenatal ultrasound, provided they have been trained to use the equipment competently and safely. n Consideration should be given to training new ultrasound providers on: infection control measures; proper cleaning and disinfection of equipment and of care areas between scans; appropriate methods for adjusting ultrasound system controls to optimize images; calculation of best obstetric estimate of gestational age; when and when not to re-date pregnancies; and special counselling considerations related to fetal loss and anomalies. Training should include communication and a relational approach during the conduct of the scan. n Sonography (when conducted by sonographers) can be emotionally challenging. The role may require additional training (e.g. in counselling, medical ethics and communication skills) and regular opportunities for peer support. n In communities where there may be misunderstandings about the potential benefits or harms of ultrasound, community education programmes should be considered. These should be inclusive (also open to partners and family members), culturally sensitive and flexible. n Prior to the first ultrasound appointment, parents should be provided with clear information about the clinical purpose of an ultrasound scans, along with details of the potential consequences of detecting fetal anomaly. Parents should also be informed that an ultrasound scan is a choice and not compulsory. n Ultrasound findings should be communicated in a timely and clear manner that the woman and her partner can understand. Opportunities to ask questions should be provided. n Attention should also be paid to helping health workers and women understand the limitations of ultrasound in predicting fetal weight, that a positive fetal heartbeat does not rule out the possibility of future pregnancy loss, and that some anomalies may not be apparent, especially early in pregnancy. Counselling and other considerations n In some contexts, health workers should be aware of the potential implications of revealing fetal sex following an antenatal scan. In these contexts, health workers should consider whether disclosure of fetal sex is appropriate. n Since ultrasound may detect fetal abnormalities, the provision of associated support services for parents is important. Parents may require counselling and access to social support networks if an abnormal diagnosis is possible or confirmed. n To keep fetal exposure to ultrasound as low as possible, the as low as reasonably achievable (ALARA) principle should be applied, with scans conducted in the shortest possible time and with the lowest power levels that are compatible with obtaining relevant diagnostic information. n Health system managers must be aware of the risk of medico-legal exposure and develop mechanisms to protect the clinicians performing imaging ultrasound. One way of doing this could be through the provision of a consent form explaining the limitations of imaging ultrasound before it is performed. Limitations may include the fact that confirming a viable fetus does not rule out the possibility of future pregnancy loss or other pregnancy complications, fetal anomalies cannot always be identified, and fetal weight estimation may not be accurate.