Turning the pyramid of prenatal care.

The current approach to prenatal care, which involves visits at 16, 24, 28, 30, 32, 34 and 36 weeks and then weekly until delivery, was established 80 years ago. The high concentration of visits in the third trimester implies, firstly, that most complications occur at this late stage of pregnancy and, secondly, that most adverse outcomes are unpredictable during the first or even second trimester. This review presents evidence that many pregnancy complications can now be predicted at an integrated first hospital visit at 11-13 weeks by combining data from maternal characteristics and history with findings of biophysical and biochemical tests. It is therefore proposed that the traditional pyramid of care should be inverted with the main emphasis placed in the first rather than third trimester of pregnancy.