Prenatal Androgen and Skills

NCT07627113 | Enrolling By Invitation

• 1 other identifier: Androgen and Skills
• Study Type: observational
• Target: 94
• Locations: 1 country
• Sites: 1

Brief Summary

Due to the difficulties and risks of directly measuring prenatal hormone levels, biomarkers that indirectly reflect this exposure are used in research. In this context, the ratio of second to fourth finger length (2D:4D) is widely preferred because it is an easily applicable and non-invasive measurement. Evidence shows that 2D:4D stabilizes from the second trimester of pregnancy onward and exhibits strong sex differences across populations. The 2D:4D ratio is generally lower in men than in women. 2D is more strongly influenced by prenatal estrogen, while 4D is more strongly influenced by prenatal testosterone; this occurs during the first trimester of intrauterine fetal development. To our knowledge, studies examining the relationship between the 2D:4D ratio, an indirect indicator of prenatal androgen exposure, and dexterity and tactile discrimination are limited. Accordingly, the planned study aims to evaluate the relationship between the 2D:4D ratio and fine motor skills and tactile discrimination in healthy young adults.

Conditions

Health Adults

Keywords

Digit Ratios; Prenatal Androgens; Motor Skills; Two-Point Discrimination; Tactile Acuity

Outcome Measures

Primary Outcomes (3)

• 2-point discrimination test

  To perform 2-point discrimination tests, the Baseline® two-point discriminator will be used. Measurements will be applied to the distal phalangeal pulp of the index finger on both hands while participants are seated in a comfortable position with their eyes closed. The test will begin at a distance of 8 mm, allowing participants to perceive the stimulus as two points, and then the distance will be gradually reduced. After 5 mm, measurements will continue at 1 mm intervals. In each application, both contact points will be applied to the skin simultaneously and with equal pressure, and participants will be asked to indicate whether the perceived stimulus is a single point or two points.

  12 months

• Digit Ratio

  Measurements will be taken after participants' hands are placed on a flat surface with palms facing upwards. Finger length is defined as the distance from the midpoint of the proximal crease line where the finger joins the palm to the distal point of the fingertip. Measurements will be performed using a digital caliper with 0.01 mm accuracy, two separate measurements will be taken for each finger, and the average value will be recorded. Based on the obtained measurements, the 2D:4D finger ratio will be calculated by dividing the 2D length by the 4D length in both hands .

  12 months

• Fine motor skills

  The test will be administered according to standard procedure while participants are seated at a table. Participants will be asked to place the pegs into the corresponding holes as quickly and accurately as possible within the specified time (30 seconds). In the dominant and non-dominant hand tests, participants will be asked to place pegs with one hand for 30 seconds, while in the both-hand test, the simultaneous use of both hands will be evaluated. The number of correctly placed pegs for each subtest will be recorded, and higher scores will be considered as better fine motor skill performance.

  12 months

Study Arms (1)

Healthy adults

Young and healthy adults aged 18-40

Other: Digit Ratio; Behavioral: Fine motor skills; Behavioral: Tactile Discrimination

Interventions

Digit Ratio OTHER

The second (2D) and fourth (4D) finger lengths of the participants will be measured separately in both hands by a physiotherapist with over thirteen years of clinical experience.

Healthy adults

Fine motor skills BEHAVIORAL

Hand dexterity will be assessed using the Purdue Pegboard Test. The test will be administered according to standard procedure with participants seated at a table. Participants will be asked to place the pegs into the corresponding holes as quickly and accurately as possible within a specified time (30 seconds).

Healthy adults

Tactile Discrimination BEHAVIORAL

To perform the 2-point discrimination tests, the Baseline® two-point discriminator will be used. Measurements will be applied to the distal phalangeal pulp of the index finger on both hands while participants are seated in a comfortable position with their eyes closed.

Healthy adults

Eligibility Criteria

• Age: 18 Years - 40 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)
• Sampling Method: Non-Probability Sample

Study Population

\- Healthy individuals aged 18-40

You may qualify if:

• Healthy individuals aged 18-40
• Having sufficient visual and auditory function to understand and administer the test,
• Voluntary agreement to participate in the study and providing informed consent.

You may not qualify if:

• Individuals with any musculoskeletal pathology,
• History of upper extremity trauma,
• Individuals diagnosed with metabolic, neurological, or genetic diseases,
• Individuals with a history of hand surgery within the last 6 months,
• Pregnancy or breastfeeding.

Sponsors & Collaborators

• Nigde Omer Halisdemir University: lead

Study Sites (1)

Nigde Omer Halisdemir University

Niğde, Merkez, Turkey (Türkiye)

Location

Related Publications (2)

• Butovskaya M, Adam Y, Batsevich V, Shackelford TK, Fink B. Associations between 2D:4D from direct and radiographic measurements with handgrip strength in young adult Tuvans. Early Hum Dev. 2024 Jun;193:106037. doi: 10.1016/j.earlhumdev.2024.106037. Epub 2024 May 8.

  PMID: 38743999 RESULT

• Fink B, Manning JT, Neave N, Tan U. Second to fourth digit ratio and hand skill in Austrian children. Biol Psychol. 2004 Nov;67(3):375-84. doi: 10.1016/j.biopsycho.2004.03.012.

  PMID: 15294393 RESULT

MeSH Terms

Interventions

Digit Ratios

Intervention Hierarchy (Ancestors)

Anthropometry; Physical Examination; Diagnostic Techniques and Procedures; Diagnosis; Body Weights and Measures; Investigative Techniques; Biometry; Epidemiologic Measurements; Public Health; Environment and Public Health

Study Officials

• Rabia ZORLULAR

  Nigde Omer Halisdemir University

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: OTHER
• Time Perspective: CROSS SECTIONAL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal investigator

Study Record Dates

• First Submitted: May 30, 2026
• First Posted: June 4, 2026
• Study Start: July 1, 2026
• Primary Completion (Estimated): July 1, 2027
• Study Completion (Estimated): July 1, 2027
• Last Updated: June 4, 2026

Record last verified: 2026-05

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)