In the fifth sentence of the results section, on page 2, in above article, the word older should be replaced by younger. The full sentence should read:
“The mothers on Åland were on average 6 months (95% CI 3.6; 9.6 months) younger than those in Helsinki.”
On page 3, in table 2. Under the column P for interaction, the 0.003 should be moved one line down to “maternal age (centred age 28 years)”