Page 107 - Fertility in Women with Rheumatoid Arthritis Vruchtbaarheid van vrouwen met reumatoïde artritis

The majority of the PARA subjects had been contacted in 2013-2014 for a questionnaire on fertility.22 As a result, addresses were up to date whenever possible. Patients currently living outside of the Netherlands or Belgium were excluded.
Ethical approval
The original PARA study, as well as the current follow-up study, were performed according to the Declaration of Helsinki, and were approved by the Medical Ethics Review Committee of the Erasmus MC.
Data collection
During the original PARA study,20 patients were visited at their homes before, during, and after pregnancy, with the nal visit 6 months postpartum. Each assessment consisted of a questionnaire driven interview on disease characteristics and use of medication, measurement of disease activity, and drawing of serum samples.
For the current study, patients received an information letter, and thereafter were contacted by telephone. Patients who gave informed consent, were visited at their home address for blood sampling, and they completed an online questionnaire including questions on menstrual cycle, age at menarche, hormone use, and other possible iatrogenic causes for amenorrhoea.
Measurements
Disease activity was measured during the PARA study visits using the Disease Activity
Score assessing 28 joints (DAS28) for tenderness and swollenness, combined with 7 serum C-reactive protein (CRP) levels.23
Serum samples were stored at -80oC. Serum AMH levels were measured in the
samples from all preconception and 6 month postpartum PARA study assessments,
as well as in the newly acquired samples from the follow-up visit.
AMH values were measured using the picoAMH assay, provided by Ansh labs
(Houston, Texas, USA).24,25 Inter and intra assay coef cients of variation were both <
5%.
Controls
Serum AMH levels in patients were compared to a group of healthy controls. This international reference cohort existed of 554 healthy adult women, aged 18-47 years, who had a regular menstrual cycle and/or were proven fertile.26 AMH levels in controls were originally reported as measured by the Beckman Coulter Gen II Assay. Therefore,
AMH in RA – longitudinal
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