You asked

Please provide the most recent data on the number of pregnancies in the UK that continue beyond 41 weeks, or more widely statistics on the length of pregnancy.

We said

Live births in England and Wales in 2016 by gestation are published in table 7 of our birth characteristics release:

https://www.ons.gov.uk/peoplepopulationandcommunity/birthsdeathsandmarriages/livebirths/datasets/birthcharacteristicsinenglandandwales

This represents the latest data available for England and Wales; data for 2017 is expected to be published in October/November 2018.

To compile UK data you will need to contact National Records of Scotland and Northern Ireland Statistics and Research Agency.

Special extracts and tabulations of births data for England and Wales are available to order (subject to legal frameworks, disclosure control, resources and agreements of costs, where appropriate). Such enquiries should be made to: vsob@ons.gov.uk

Please contact the Vital Statistics Outputs team directly in order to discuss any further data requirements.