Prenatal Hormonal Markers and Sleep Characteristics in Young Adults With Joint Hypermobility

The Beighton Scoring System is widely used to distinguish individuals with generalized joint hypermobility from those without. The Beighton Scoring System consists of: • Passive dorsiflexion of the fifth metacarpophalangeal joint • Passive hyperextension of the elbow • Passive hyperextension of the knee joint • Passive placement of the thumb on the flexor side of the forearm • Forward flexion of the trunk In adults up to 50 years of age, a score of ≥5 out of 9 indicates joint hypermobility, while in adults over 50, a score of ≥4 out of 9 is considered positive for joint hypermobility.

The lengths of the second (2D) and fourth (4D) digits will be measured separately on both hands. Measurements will be taken with the participants' hands placed on a flat surface with the palms facing upward. Digit length will be defined as the distance from the midpoint of the proximal crease at the base of the finger to the distal tip of the finger. A digital caliper with a precision of 0.01 mm will be used, and two separate measurements will be obtained for each finger, with the mean value recorded. Based on these measurements, the 2D:4D digit ratio will be calculated for each hand by dividing the length of the second digit by that of the fourth digit. To enhance reliability, assessments will be performed independently by two different researchers, and inter-rater agreement will be evaluated.

The Pittsburgh Sleep Quality Index is a self-report questionnaire that assesses sleep quality over a one-month period. The measure consists of 19 items divided into 7 components that produce a single overall score and takes 5-10 minutes to complete. Component scores are as follows: • Subjective sleep quality • Sleep latency (time to fall asleep) • Sleep duration • Habitual sleep efficiency (percentage of time spent in bed) • Sleep disturbances • Use of sleeping pills • Daytime dysfunction Each item is scored on a 0-3 scale. The seven component scores are then summed to create an overall score ranging from 0-21, with lower scores indicating better sleep quality