The Fertility Indicator Equation Using Serum Progesterone and Urinary Pregnanediol-3-Glucuronide for Assessment of Ovulatory to Luteal Phase Transition
Usala et al.
The finding, in our words
The Fertility Indicator Equation produced a clear signature of consecutive positive values when applied to daily serum progesterone or urinary pregnanediol-3-glucuronide levels, reliably signalling the transition from ovulatory to luteal phase. This approach could enable home-based fertility monitoring through self-collected urine samples.
A paraphrase to the Library’s standard, never the abstract. The source is one link away and is always the authority.
All five at-home urine ovulation predictor kits demonstrated high accuracy (92–97%) when compared with blood LH levels, though sensitivity varied widely from 38% to 77% with Clinical Guard the lowest. Patient experience was comparable across kits, though Clinical Guard was slightly less favoured for future use.
In 20 women providing 73 paired samples across menstrual‑cycle phases, urinary metabolites measured at home correlated strongly with serum hormone concentrations (estradiol R²=0.96, progesterone R²=0.95, LH R²=0.98). When the derived equations were applied to a separate set of 20 users, predicted serum values correlated 0.92–0.94 with actual measurements. This suggests home urine testing could substitute for clinic blood draws in routine fertility monitoring, though the cohort was limited to women with normal cycles.
Self-collected salivary progesterone and the ratio of estradiol to progesterone showed strong agreement with serum levels, supporting the use of saliva as a noninvasive matrix for monitoring the menstrual cycle.
In a large study using self-collected capillary blood, current vaping and smoking were independently associated with lower levels of anti-Müllerian hormone, a marker of ovarian reserve. This demonstrates the utility of decentralised capillary sampling for large-scale epidemiological research on reproductive health.
This study demonstrates that a memristor sensor can identify distinct electrical signatures in saliva and urine corresponding to different ovulation phases, suggesting a potential route for noninvasive home fertility monitoring.