Purpose: Developmental dysplasia of the hip (DDH) joint is a complex condition that may lead to severe problems. Ultrasound scan (USS) in the first four-to-six weeks of life is considered the gold-standard for diagnosis while the Pavlik harness (PH) is a widely utilized method as first-line treatment. The purpose of this study is to compare clinical outcomes of infants with DDH in relation to the timing and frequency of USS following application of the PH.Methods: Retrospective data were collected over a 5-year period from February 2017 to February 2022. We included patients who underwent the first USS post-diagnosis and PH application in two, three, four and six weeks. Two-hundred-twenty-five patients were included and divided in four groups according to timing of the first follow-up: week-2, n = 13; week-3, n = 66; week-4, n = 95; and week-6, n = 51. For every patient Graf classification, treatment length and number of follow-ups were documented.Results: Week-3 and week-4 groups displayed a statistically significant shorter treatment length compared to week-6 group (p value < 0.001), while also demonstrating a lower number of sonographic follow-ups per patient compared to both week-6 (p value < 0.001) and week-2 (p value = 0.002 vs week-3; p value < 0.001 vs week 4). Week-4 group presented the highest treatment completion (56%) on first visit post-diagnosis. Conservative treatment with PH failed in 1.8% (4/225) and displayed no significant difference among all subgroups.Conclusions: Differences in timing of first USS post-DDH diagnosis and initiation of treatment can lead to discrete outcomes with implications to the clinical outcome and cost effectiveness.