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Incidence of neonatal hip instability: are there seasonal variations?
Insights
Birth season impacts infant hip instability. This study found a higher incidence of congenital hip displacement in newborns during late winter and early spring months.
Area of Science:
- Pediatrics
- Orthopedics
- Epidemiology
Background:
- Congenital hip instability, also known as developmental dysplasia of the hip (DDH), is a common neonatal condition.
- Previous research has explored various risk factors for DDH, but seasonal influences remain less understood.
Purpose of the Study:
- To investigate the potential association between the season of birth and the incidence of neonatally diagnosed hip instability in Eastern England.
- To analyze monthly birth and hip instability data to identify any seasonal patterns.
Main Methods:
- Retrospective analysis of maternities and diagnosed cases of congenital hip displacement.
- Data collected over an 8-year period (1979-1986) in Eastern England.
- Monthly incidence rates were calculated and compared.
Main Results:
- The study analyzed 185,744 maternities and 154 cases of congenital hip displacement.
- A significant seasonal variation was observed, with a peak incidence in January, February, March, and April.
- Incidence progressively declined in the months following spring.
Conclusions:
- The season of birth appears to influence the incidence of neonatally diagnosed hip instability.
- Late winter and early spring births are associated with a higher risk of congenital hip displacement.
- The underlying causes for this observed seasonal variation require further investigation.
Abstract:
We wanted to establish whether the season of birth affected the incidence of neonatally diagnosable hip instability in Eastern England. Data relating the numbers of maternities to the numbers of cases of congenital displacement of the hip diagnosed in neonates were analyzed month by month over a period of 8 years. The study covered 185,744 maternities and 154 cases of displaced hips during the period 1979-1986. While there were wide fluctuations in the monthly incidence, there was a striking excess of the malformation in late winter and early spring, i.e. in January, February, March and April, and a progressive decline in the succeeding months. The cause or causes of the seasonal variation are unknown.
