Objective: We studied the relationship between cervical mucus evaluations and daily fertility examinations in order to find monitoring techniques that can predict optimal mucus one day before it occurs.
Methods: Twenty-three healthy young female volunteers were followed during one spontaneous cycle with serial measurements of serum estradiol, progesterone, LH and FSH, urinary LH, and transvaginal ultrasound measurements of endometrial thickness and follicles. Data were related to cervical mucus scores.
Results: All cycles were ovulatory with optimal mucus, but in 14 optimal mucus was present for only one day. Echographic measurement of the leading follicle (mean diameter > or = 18 mm) could predict the day of optimal mucus in 78% and estradiol (> 700 pmol/l) in 83% of the cases. These two measurements combined predicted optimal mucus in 100% of the investigated women one day in advance.
Conclusion: Optimal cervical mucus parameters can be predicted one day in advance by serial measurements of serum estradiol and follicular diameters.