Background: The objectives of this study were to assess the feasibility of and compliance to collecting urine samples in pre- and postmenarcheal girls and to determine if a less than daily collection frequency was sufficient for assessing ovarian function.
Methods: Twenty-five postmenarcheal girls (11-17 years) collected samples using either a two or a three samples/week protocol during one menstrual cycle. Exposure and mean estrone-1-glucuronide (E1G) and pregnanediol glucuronide concentrations were calculated, and evidence of luteal activity (ELA) was evaluated. Sixteen premenarcheal girls (8-11 years) collected one sample/month for six consecutive months. Samples were analyzed for E1G concentration. Participant compliance was calculated using dates on the urine samples and paper calendars.
Results: Participants collecting three samples/week were more compliant to the protocol than those collecting two samples/week (83.6%±2.6% vs. 66.8%±6.6%; p=0.034). There were no differences (p>0.10) regarding paper calendar return (81.8%±12.2% vs. 92.9%±7.1%), recording menses (55.6%±17.6% vs. 92.3%±7.7%) or sample collection (88.9%±11.1% vs. 84.6%±10.4%) between the two protocols. The average cycle length was 30.5±1.3 days and 32% of cycles had ELA. The premenarcheal girls were 100% compliant to the protocol. Only 68.8% of participants returned the paper calendar and 81.8% of those participants recorded sample collection. The average E1G concentration was 15.9±3.8 ng/mL.
Conclusions: Use of a less than daily collection frequency during one menstrual cycle in postmenarcheal, adolescent girls is feasible and provides informative data about ovarian function. Collection of one sample/month in premenarcheal girls is feasible and detects the expected low E1G concentrations. Alternate strategies to the use of a paper calendar should be considered.
Keywords: epidemiology; estrone-1-glucuronide; menarche; pregnanediol glucuronide; reproductive hormone analysis.