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The 35/39 Trial

Induction of labour versus expectant management for women over 35 years of age

Welcome to the 35/39 Trial website

British women are increasingly delaying childbirth. The longer they wait the greater the risk of pregnancy complications. One concern is the increased risk of stillbirth (baby dying before birth).

The aim of our trial is to find out how best to manage the pregnancies of women expecting their first baby over the age of thirty-five years.

Labour is a natural process that usually starts on its own. Sometimes it needs to be started artificially; this is called ‘induced labour’. We don’t know whether it is better to induce labour a week early (39 weeks) for pregnant women who are over thirty-five years old, or to wait for them to go into labour spontaneously. Starting labour a week early might prevent a small number of stillbirths, but it might also lead to longer labours and possibly more Caesarean births. To find out, we need to compare these two different ways of managing women.

We will put women into two groups each with a different management plan. The results will be compared to see which is better. To ensure the groups are the same to start with, each patient is allocated by chance. This is known as a randomised trial.

The two groups are:
  1. Induction of labour at 39 weeks
  2. No intervention until the normal time for inducing labour between 7 and 14 days overdue.

The main purpose is to see whether inducing the labour of women over 35 years of age at 39 weeks, increases, or decreases their risk of needing a caesarean birth.

We plan to recruit 630 women from 12 centres across the UK over two years.

Recruitment status

If you would like more information on the trial or are interested in participating, please click here.

If you are an investigator and are looking for the randomisation website, please click here.

Last updated : Tuesday, July 30, 2013 7:56 AM