Operative deliveries in low-risk pregnancies in The Netherlands: primary versus secondary care.

BACKGROUND

In The Netherlands, 35 percent of births take place in "primary care" to women considered at low risk and during labor, approximately 30 percent are referred to "secondary care." High-risk women and some low-risk women deliver in secondary care. This study sought to compare planned place of birth and incidence of operative delivery among women at low risk of complications at the time of onset of labor.

METHODS

A retrospective analysis was conducted of data about births in The Netherlands during 2003 that were recorded routinely in the Netherlands Perinatal Registry. Mode of delivery was analyzed for women classified as low risk at labor onset according to their planned place of birth (intention-to-treat analysis). The primary outcome was the rate of operative deliveries (vacuum or forceps extraction or cesarean section).

RESULTS

Women at low risk who planned to give birth, and therefore labored and delivered in secondary care, had a significantly higher rate of operative deliveries than women who began labor in primary care where they intended to give birth (18% [3,558/19,850] vs 9% [7,803/87,187]) (OR 2.25, 95% CI 2.00-2.52). For cesarean section, the rates were 12 percent (2,419/19,850) versus 3 percent (2,990/87,817) (OR 3.97, 95% CI 3.15-5.01), irrespective of parity.

CONCLUSIONS

The rate of operative deliveries was significantly lower for low-risk pregnant women who gave birth in a primary care setting compared with similar women who planned birth in secondary care. As with any retrospective analysis, it was not possible to eliminate bias, such as possible differences between primary and secondary care in assignment of risk status. In addition, known risk factors for interventions, technologies such as induction of labor and fetal monitoring, are only available in secondary care. These findings clearly demonstrate the need for a prospective study to examine the relationship between planned place of birth and mode of delivery and neonatal and maternal outcomes.