Phe levels over menstrual cycle in PKU
Research type
Research Study
Full title
A feasibility study to determine whether there is variation in blood phenylalanine levels across the menstrual cycle in healthy women with Phenylketonuria.
IRAS ID
360434
Contact name
Karolina Stepien
Contact email
Sponsor organisation
Northern Care Alliance NHS Foundation Trust
Duration of Study in the UK
0 years, 11 months, 30 days
Research summary
Blood phenylalanine (Phe) levels are likely to change during the monthly period in women with PKU. We want to study this because some women report that when they started their period changes in Phe resulted in questions about adherence to the low protein diet. Women undergoing sapropterin testing have reported changes in Phe during their period which has complicated decisions around responsiveness.
We propose a feasibility pilot study recruiting 10 women aged under 40 years old from the metabolic unit at Salford Royal Hospital, Northern Care Alliance NHS Foundation Trust. Women will be asked to complete a diary of their period for two months which will help decide the best days to plan tests for hormone and Phe levels. Hormone and Phe levels will be tested at specifically chosen time points during the different parts of the period (menstrual cycle), for 3 cycles to ensure we have representative results. Participants will be asked to complete a diary to check that any changes in Phe levels are not related to appetite or diet.
We will also complete a questionnaire study to find out whether and how periods have impacted on women’s experiences of having PKU.REC name
North West - Greater Manchester South Research Ethics Committee
REC reference
25/NW/0325
Date of REC Opinion
22 Oct 2025
REC opinion
Favourable Opinion