What are the recommended monitoring protocols for fetal growth in pregnancies complicated by maternal obesity?

In pregnancies complicated by maternal obesity, the recommended monitoring protocols for fetal growth include offering a risk assessment for fetal growth restriction at the first antenatal (booking) appointment and again in the second trimester. This assessment should consider guidance from professional bodies such as the Royal College of Obstetricians and Gynaecologists or the NHS saving babies' lives care bundle version 2.

After 24+0 weeks, symphysis fundal height measurement should be offered at each antenatal appointment (but no more frequently than every 2 weeks) for women with a singleton pregnancy, unless the woman is having regular growth scans. These measurements should be plotted onto a growth chart in line with the NHS saving babies' lives care bundle version 2.

If the symphysis fundal height is found to be large or small for gestational age, an ultrasound scan for fetal growth and wellbeing should be considered or offered, respectively. The urgency of ultrasound for small size may depend on additional clinical findings such as reduced fetal movements or raised maternal blood pressure. Routine ultrasound scans after 28 weeks are not recommended for uncomplicated singleton pregnancies.

Additionally, from 24+0 weeks, women should be informed about fetal movements and advised to report any concerns about reduced fetal movements promptly. Assessment of the woman and baby should be done if concerns arise.

These protocols aim to monitor fetal growth effectively in the context of maternal obesity, which is a risk factor for fetal growth abnormalities, by combining clinical measurements and targeted ultrasound assessments rather than routine late pregnancy scans.

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