About the SOLVE Trial

Some women expecting babies may need help going in to labour, or need to bring the birth of their child forward, for a number of reasons. The first step is to make the cervix (neck of the womb) open up, shorten and soften, which is called ripening. There are different methods that can be used to help ripening. These include a pessary called dinoprostone (or PROPESS) that is placed in the vagina. This provides a hormone that helps to prepare the cervix for labour. In the UK this drug is usually given to women expecting their first baby and is sometimes given to women in subsequent pregnancies.  It is effective but can have side effects.

In recent years there has been more interest in using non-drug methods of ripening, as these have fewer side effects, but may not be as fast at bringing on labour as drugs. The study would like to find out if a new method, using a cervical dilator (called DILAPAN-S) to stimulate the cervix in to labour, would be more effective. The SOLVE study will find this out.

The study will invite 860 women requiring induction to take part, half of whom will receive PROPESS and half will receive DILAPAN-S. The study will be open to recruitment for 2 years.

Eligible women, whose doctor believes they require an induction of labour, will be appraoched about taking part in the study and provided with a patient information leaflet (PIL). Women who are happy to take part in the study, will be asked to sign a consent form. The person who takes consent will then enter details into a telephone system. This will allocate the woman to either the PROPESS or the DILAPAN-S group. The decision about which group a woman would go into will be made by chance, rather like the toss of a coin. This is important because it ensures that the two methods of induction can be tested fairly against each other. We will also let your GP know that you took part in the SOLVE study, with your consent.

If the cervix is ripening slowly, but you and your baby are well, the initial method will be removed and may be replaced.  You may be offered a second pessary after 24-32 hours (if in the PROPESS group) or a second set of DILAPAN-S rods after 12 hours (if in the DILAPAN-S group). If the cervix is ripened but contractions have not started, your waters are broken artificially and an oxytocin infusion is started to allow labour to progress (women given Dilapan-S have a 40% chance of receiving oxytocin compared to a 20% chance for women given Propess). Taking part in the study won’t affect the care you receive, and you will be cared for as you would ordinarily within the NHS.

Information about your labour will be collected by the midwife and be kept confidentially. We will record details of your childbirth experience and any infections you and your baby acquire whilst in hospital. You will also be asked to fill in a short questionnaire about your labour experience. There are no further tests or hospital visits connected with this study. No payments are available for taking part in this study.

Women who fulfil all the following criteria will be eligible to be randomised into the trial:

Inclusion criteria

1. 1. ≥ 16 years of age
   2. Able to provide informed consent
   3. Singleton pregnancy
   4. Indication for IoL
   5. Pregnancy ≥ 37.0 weeks (assessed as an agreed gestational age by ultrasound dating scan)
   6. Living fetus with vertex presentation
   7. Intact membranes

Exclusion criteria

1. Women already receiving oxytocin
2. Diagnosis of fulminant preeclampsia / eclampsia
3. Contraindication to PROPESS or DILAPAN
4. If PROPESS for IoL is non-compliant with local policy
5. Enrolled in other randomised controlled trials of an IMP or device for cervical ripening or induction of labour