Ovulation occurs on 1 day during each menstrual cycle (even if multiple follicles are involved), and the several days preceding ovulation are when intercourse is most likely to result in pregnancy. Collectively, the potentially fertile days up to and including the day of ovulation are called the “fertile window” (1). Since the 1930s, several biomarkers of the fertile window have been investigated for the purposes of empowering women and couples seeking to use fertility-awareness based methods or natural family planning to avoid pregnancy, as well as to expand understanding of human reproductive physiology.
Indirect evidence of the occurrence of ovulation, which is generally accepted, is an increase in plasma or serum progesterone. Pelvic ultrasonography can estimate the probable time of ovulation within 12 h. There is a close association between the rise in progesterone, luteinizing hormone (LH) and oestrogen peaks and ovulation. A WHO study reported that ovulation occurred at a median time of 8 h after the rise in plasma progesterone, 15 h after the LH peak and 24 h after the oestrogen peak. The basal body temperature (BBT) method is the most effective in determining the premenstrual infertile period, but it is unreliable for an accurate determination of ovulation and the postmenstrual infertile period. Nor is BBT an effective method of predicting ovulation during postpartum lactational amenorrhoea. Therefore, BBT is usually used as a secondary indicator of ovulation and is combined with more reliable indicators. Observed changes in cervical mucus patterns can be used to define the probable fertile period, although this method produces a wide range of days. The peak mucus symptom is closely correlated with ovulation. Mucus symptoms can be used as a guide for the timing of blood or urine samples for estimation of LH, oestrogen and progesterone or their metabolites. Symptothermal methods incorporate other symptoms such as cervical changes, intermenstrual pain, breast tenderness and backaches, but these are secondary signs of ovulation and are recommended to be used in conjunction with mucus and BBT.
To compare previously used algorithms to identify anovulatory menstrual cycles in women self-reporting regular menses.
Prospective cohort study.
Western New York. PATIENT(S): Two hundred fifty-nine healthy, regularly menstruating women followed for one (n=9) or two (n=250) menstrual cycles (2005-2007). INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Prevalence of sporadic anovulatory cycles identified using 11 previously defined algorithms that use E2, P, and LH concentrations. RESULT(S): Algorithms based on serum LH, E2, and P levels detected a prevalence of anovulation across the study period of 5.5%-12.8% (concordant classification for 91.7%-97.4% of cycles). The prevalence of anovulatory cycles varied from 3.4% to 18.6% using algorithms based on urinary LH alone or with the primary E2 metabolite, estrone-3-glucuronide, levels. CONCLUSION(S): The prevalence of anovulatory cycles among healthy women varied by algorithm. Mid-cycle LH surge urine-based algorithms used in over-the-counter fertility monitors tended to classify a higher proportion of anovulatory cycles compared with luteal-phase P serum-based algorithms. Our study demonstrates that algorithms based on the LH surge, or in conjunction with estrone-3-glucuronide, potentially estimate a higher percentage of anovulatory episodes. Addition of measurements of postovulatory serum P or urine pregnanediol may aid in detecting ovulation.
Jerilynn C Prior et al., 2018·Int J Environ Res Public Health·
Open Access
Approximately 33% of normal-length (21⁻35 days) cycles have subclinical ovulatory disturbances and lack sufficient progesterone, although their normal length ensures enough estrogen. Subclinical ovulatory disturbances are related to significant premenopausal spine bone loss (-0.86%/year). Molimina, non-distressing premenstrual experiences, may detect ovulation within normal-length cycles. This prospective study assessed the relationship between molimina and ovulation. After 1-cycle of daily diary and first morning urine collections, women answered the Molimina Question (MQ): "Can you tell by the way you feel that your period is coming?" and were invited to share (a) predictive premenstrual experience(s). A 3-fold increase in follicular-luteal pregnanediol levels confirmed ovulation. In 610 spontaneously menstruating women (not on hormonal contraception, mean age 31.5 ± 5.3, menarche age 12.7 ± 1.5, cycle length [CL] 29 days, MQ positive in 89%), reported premenstrual experiences which included negative moods (62%), cramps (48%), bloating (39%), and front (26%) or axillary (25%) breast tenderness. Of 432 women with pregnanediol-documented cycles, 398 (92%) were ovulatory (CL: 29 ± 5) and 34 (8%) had ovulatory disturbances (CL: 32 ± 14). Women with/without ovulatory cycles were similar in parity, body mass index, smoking, dietary restraint and the MQ; ovulatory-disturbed cycles were longer. Molimina did not confirm ovulation. A non-invasive, inexpensive ovulation indicator is needed to prevent osteoporosis.
Su HW et al., 2017·Bioengineering & translational medicine
The ability to identify the precise time of ovulation is important for women who want to plan conception or practice contraception. Here, we review the current literature on various methods for detecting ovulation including a review of point-of-care device technology. We incorporate an examination of methods to detect ovulation that have been developed and practiced for decades and analyze the indications and limitations of each-transvaginal ultrasonography, urinary luteinizing hormone detection, serum progesterone and urinary pregnanediol 3-glucuronide detection, urinary follicular stimulating hormone detection, basal body temperature monitoring, and cervical mucus and salivary ferning analysis. Some point-of-care ovulation detection devices have been developed and commercialized based on these methods, however previous research was limited by small sample size and an inconsistent standard reference to true ovulation.