Condition category
Nutritional, Metabolic, Endocrine
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status

Plain English Summary

Not provided at time of registration

Trial website

Contact information



Primary contact

Dr Helen R Murphy


Contact details

University of Cambridge Metabolic Research Laboratories
Level 4
Institute of Metabolic Science
Box 289
Addenbrooke’s Hospital
Hills Road
United Kingdom
+44 (0)1223 769079

Additional identifiers

EudraCT number number

Protocol/serial number

Version 1.3 Feb 9th 2009

Study information

Scientific title

Evaluation of the gut absorption rate of glucose during an evening meal and breakfast: a prospective three-centre observational cohort study in pregnant women with type 1 diabetes


CLIP - 01

Study hypothesis

We aim to evaluate whether estimates of glucose absorption rates differ according to the meal type and composition (i.e., breakfast versus evening meal) and according to gestational age during pregnancy. This evaluation will inform the future development of insulin dose adjustment algorithms for use in closed loop systems during pregnancy in women with type 1 diabetes.

Ethics approval

Cambridgeshire 1 Research Ethics Committee approved on the 16th December 2008 (ref: 08/H0304/128)

Study design

Prospective multicentre observational cohort study

Primary study design


Secondary study design

Cohort study

Trial setting


Trial type


Patient information sheet

Not available in web format, please use the contact details below to request a patient information sheet


Pregnant women with pre-existing type 1 diabetes


The same study protocol will be performed on two occasions during early (12 - 16 weeks gestation) and late (28 - 32 weeks gestation) pregnancy. On each occasion participants will eat a tracer-enriched, more slowly-absorbed evening meal, followed by an overnight stay with a tracer enriched, more rapidly absorbed breakfast meal the next morning. A variable subcutaneous (SC) insulin infusion will continue throughout using algorithm control aiming to maintain plasma glucose between 3.5 - 7.8 mmol/L.

Intervention type



Not Applicable

Drug names

Primary outcome measure

Document the changes in gut absorption of a more slowly absorbed medium sized evening meal and a more rapidly absorbed medium sized breakfast meal during pregnancy by the model-based analysis of the data using computational approach previously described by Hovorka et al. The gut absorption rates will be compared using the root mean square error (RMSE).

Secondary outcome measures

Metrics obtained by modelling of tracer glucose:
1. BIOmod*: meal bioavailability
2. Tmax, mod*: time-to-maximum of the model-derived gut absorption
3. T25%, mod*, T50%, mod*, T75%, mod*: time to 25%, 50%, and 75% of the model-derived gut absorption
4. AUC0-420, mod*: the area-under-curve of the model-derived gut absorption

Analysis of plasma glucose:
5. Cmax,PG, tmax, PG: the concentration-time profile of plasma glucose concentration following meal digestion/start of glucose infusion

Analysis of plasma insulin:
6. AUCPI(0-240), Cmax, PI, tmax, PI for the concentration-time profiles of plasma insulin

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. Signed informed consent obtained before study-related activities. Study-related activities are any procedure that would not have been performed during standard medical care.
2. The participant is between 16 and 44 years of age (inclusive)
3. The participant has type 1 diabetes, as defined by World Health Organization (WHO) for at least 12 months and has had a viable singleton pregnancy confirmed by ultrasound
4. The participant has been on insulin pump or multiple daily injection (MDI) therapy for at least 6 months
5. The participant is able and willing to use a real time continuous sensor

Participant type


Age group




Target number of participants


Participant exclusion criteria

1. Non-type 1 diabetes mellitus including those secondary to chronic disease
2. Any other physical or psychological disease likely to interfere with the normal conduct of the study and interpretation of the study results such as coeliac disease or untreated hypothyroidism
3. Current treatment with drugs known to interfere with glucose metabolism such as systemic corticosteroids, non-selective beta-blockers and monoamine oxidase (MAO) inhibitors
4. Known or suspected allergy against insulin
5. Women with clinically significant nephropathy, neuropathy or proliferative retinopathy as judged by the investigator
6. Documented gastroparesis
7. Very poor glycaemic control i.e. HbA1c greater than or equal to 10%
8. Significant obesity, i.e., body mass index (BMI) at booking greater than 35 kg/m^2
9. Total daily insulin dose greater than 1.5 IU/kg at booking
10. Women who have conceived with in-vitro fertilisation (IVF) or assisted reproductive techniques

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

University of Cambridge Metabolic Research Laboratories
United Kingdom

Sponsor information


Cambridge University Hospitals NHS Foundation Trust and the University of Cambridge (UK)

Sponsor details

Box 277
Addenbrookes Hospital
Hills Road
United Kingdom
+44 (0)1223 348491

Sponsor type




Funder type


Funder name

Diabetes UK (UK) (ref: BDA 07/0003551)

Alternative name(s)

Funding Body Type

private sector organisation

Funding Body Subtype

Other non-profit organizations


United Kingdom

Funder name

National Institute for Health Research (NIHR) (UK) - Post-Doctoral Fellowship (ref: PDF/08/01/036)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Basic results (scientific)

Publication list

1. 2011 results in
2. 2012 results in

Publication citations

  1. Results

    Murphy HR, Elleri D, Allen JM, Harris J, Simmons D, Rayman G, Temple RC, Umpleby AM, Dunger DB, Haidar A, Nodale M, Wilinska ME, Hovorka R, Pathophysiology of postprandial hyperglycaemia in women with type 1 diabetes during pregnancy., Diabetologia, 2012, 55, 2, 282-293, doi: 10.1007/s00125-011-2363-6.

  2. Results

    Murphy HR, Elleri D, Allen JM, Simmons D, Nodale M, Hovorka R, Plasma C-peptide concentration in women with Type 1 diabetes during early and late pregnancy., Diabet. Med., 2012, 29, 10, e361-4, doi: 10.1111/j.1464-5491.2012.03747.x.

Additional files

Editorial Notes