[Differences between Dutch provinces in perinatal mortality and travel time to hospital]

To investigate differences in perinatal mortality between Dutch provinces and to determine the significance of risk factors including travel time from home to the hospital during labour.

Cohort study.

The study was based on 1,242,725 singleton births in 2000-2006 as recorded in the Netherlands Perinatal Registry. The influence of province on perinatal mortality was estimated, with logistic regression analysis adjusting for risk factors (age, parity, ethnicity, socioeconomic status) and care factors such as start of antenatal care and travel time.

The perinatal mortality rate in the Netherlands was 9.9 per 1000 births. The provinces with the highest mortality rates were Friesland (11.3‰), Groningen (11.1‰), Zeeland (10.6‰) and Flevoland (10.4‰). Noord-Brabant (9.2‰) and Limburg (9.2‰) had the lowest mortality rates. These differences were significantly higher for Friesland (odds ratio: 1.16; 95%-CI: 1.05-1.28) and Groningen (odds ratio: 1.13; 95%-CI: 1.02-1.26). Starting late with perinatal care, at 18 weeks of gestation or later was an important risk factor (adjusted odds ratio 1.8; 95%-CI: 1.7-1.8). Low socio-economic status could partly be associated with the higher mortality risk in Groningen. Longer travel time (≥ 20 minutes) was an independent risk factor associated with perinatal mortality. On average 19% of the women travelled ≥ 20 minutes to the hospital. In the provinces Groningen, Friesland, Flevoland and Zeeland these percentages ranged between 32 and 36%. The adjusted odds ratio of travel time was 1.7 (95%-CI 1.6-1.7).

The perinatal mortality differs per province. This can be explained by longer travel time to the hospital during labour. Late start of perinatal care and low socio-economic status also affect the mortality rate. These risk factors need to be taken into account during registration, investigation, audit and obstetric policy.