Ultrasound of the post-partum uterus

To assess the appearance of the post-partum uterus on transabdominal ultrasound, and to correlate these findings with maternal morbidity.

In a prospective observational study, 94 women were seen within 24 h of their delivery and assessed by transabdominal ultrasound. Volumetric data were calculated from measurements of intrauterine echogenic areas. All women were contacted for a telephone interview 1-4 months following their delivery to assess whether they had experienced morbidity associated with their delivery such as post-partum haemorrhage, pyrexia, prolonged hospital stay, follow-up investigations or surgical intervention.

Two areas of echogenic material were identified in the upper and lower segment of the post-partum uterus. These were assessed independently for dimensions and volumes. The upper segment area had an average thickness of 13.8 mm and an average volume of 35.6 cm(3) The lower segment/cervical area held considerably more material with an average volume of 54.8 cm(3). The mean duration of post-partum bleeding was 4.2 weeks. None of the recruited women required a blood transfusion. The average hospital stay was 4 days. Twenty-two (23%) of the participants experienced a febrile illness following delivery, and 19 (20%) were commenced on antibiotics. None of these parameters of post-partum morbidity were associated with the ultrasound findings.

In this study ultrasound evaluation in the immediate post-partum period revealed unexpectedly large volumes of echogenic material in the uterine cavity. However, such volumes of echogenic material were not associated with postnatal morbidity, and can probably be accepted as normal.