Correlation of plasma gonadotrophins and ovarian steroids pattern with symptomatic changes in cervical mucus during the menstrual cycle in normal cycling women
S Cortesi, F Zen , G Rigoni
R Sposetti
Author affiliations
International Renal Research Institute of VicenzaROR
27 healthy young Italian women were studied to evaluate their ability to identify symptomatically the potentially fertile phase of the menstrual cycle by self observation of their cervical mucus pattern as described in the Ovulation Method Billings. The women's observations were correlated with daily plasma levels of FSH, LH, estradiol-17 beta and progesterone. Ovulation was considered to occur on the day following the LH peak. The hormonal assays revealed that 2 of the 34 cycles studied were anovulatory. 24 of the 27 subjects in the study group demonstrated their ability to recognize the onset of the mucus discharge and the peak symptom from the first cycle after teaching, another two from the second cycle. The only other subject contributed an anovulatory cycle in which the hormonal assay confirmed the accuracy of her mucus observations. In the study, the mean interval between the time of ovulation as assessed and the peak symptom recorded by the subjects was 0.0 days, with a range from -2 to +1 days. The mean time interval from the first recorded symptom to the estimated day of ovulation was 6.0 days, with a range from 3 to 10 days. The study shows that young Italian women can be taught to recognize their cervical mucus pattern as described in the Ovulation Method Billings. The accuracy of their observations is demonstrated by the hormonal assays. The study also confirms the conclusion reached in earlier similar studies that there is a direct correlation between the cervical mucus symptom and the potentially fertile phase of the cycle. Research is currently being conducted on a larger number of couples employing the Ovulation Method Billings to actually regulate their fertility.
PMID 6793304 6793304 DOI 10.1016/s0010-7824(81)80005-4 10.1016/s0010-7824(81)80005-4 Cortesi et al. 1981, Cortesi 1981
Cite this article
Cortesi, S., Rigoni, G., Zen, F., & Sposetti, R. (1981). Correlation of plasma gonadotrophins and ovarian steroids pattern with symptomatic changes in cervical mucus during the menstrual cycle in normal cycling women. Contraception, 23(6), 629-641. https://doi.org/10.1016/s0010-7824(81)80005-4
Cortesi S, Rigoni G, Zen F, Sposetti R. Correlation of plasma gonadotrophins and ovarian steroids pattern with symptomatic changes in cervical mucus during the menstrual cycle in normal cycling women. Contraception. 1981;23(6):629-641. doi:10.1016/s0010-7824(81)80005-4
Cortesi, S., et al. "Correlation of plasma gonadotrophins and ovarian steroids pattern with symptomatic changes in cervical mucus during the menstrual cycle in normal cycling women." Contraception, vol. 23, no. 6, 1981, pp. 629-641.
The observation of the "Peak" mucus symptom in women using the ovulation method of natural family planning has been correlated with the estimated time of ovulation, as evaluated by indirect hormonal parameters. In 65 cycles of the 73 studied in 24 patients, there was hormonal confirmation of ovulation; in eight cycles, anovulation or luteal dysfunction was suspected. In the 65 normal cycles, 64 exhibited a Peak symptom. In those cycles, ovulation was estimated to occur from 3 days before to 3 days after the Peak symptom with a mean of 0.31 days before the Peak symptom. In 95.4% of these cycles, ovulation was estimated to occur from 2 days before to 2 days after the Peak symptom. The variation between cycles of the same patient ranged from 0 to 4 days with a mean of 1.8 days. The beginning of the mucus symptom preceded the estimated time of ovulation by an average of 5.9 days.
The contraceptive efficacy of emergency contraceptive pills containing levonorgestrel (LNG-EC) has been estimated in most previous studies by judging the day of ovulation from presumptive menstrual cycle data, thus providing poorly reliable estimates. In the present study, the efficacy of LNG-EC was determined in 393 cycles by dating ovulation on the basis of reliable hormonal and ovarian parameters validated by a database constructed in a separate study. In addition, the efficacy was determined separately for cycles in which LNG-EC was given before or after ovulation. For the 148 women who had sexual intercourse during the fertile days, the overall accumulated probability of pregnancy was 24.7, while altogether 8 pregnancies were observed. Thus, the overall contraceptive efficacy of LNG-EC was 68%. Among the 103 women who took LNG-EC before ovulation (days -5 to -1), 16 pregnancies were expected and no pregnancy occurred (p<.0001). Among the 45 women who took LNG-EC on the day of ovulation (day 0) or thereafter, 8 pregnancies occurred and 8.7 were expected (p=1.00). These findings are incompatible with the inhibition of implantation by LNG-EC in women. The same cases were also analyzed using the presumptive menstrual cycle data, and important discrepancies were detected between the two methods. The efficacy of LNG-EC has been overestimated in studies using presumptive menstrual cycle data. Our results confirm previous similar studies and demonstrate that LNG-EC does not prevent embryo implantation and therefore cannot be labeled as abortifacient.
Although widely used, the mechanisms of action of the levonorgestrel emergency contraceptive pill (LNG ECP) are still unclear. There are increasing data to indicate that LNG is particularly effective as an ECP by interrupting follicular development and ovulation. An important outstanding question is whether it has any effect on fertilization or implantation. Ninety-nine women participated; they were recruited at the time they presented with a request for emergency contraception. All women took LNG 1.5 mg in a single dose during the clinic consultation. A blood sample was taken immediately prior to ingestion of the ECP for estimation of serum LH, estradiol and progesterone levels to calculate the day of ovulation. The specimens were analyzed in a single batch. Based on these endocrine data, we estimated the timing of ovulation to be within a +/-24-h period with an accuracy of around 80%. Women were followed up 4-6 weeks later to ascertain pregnancy status. The effectiveness of ECP when taken before and after ovulation was determined. Three women became pregnant despite taking the ECP (pregnancy rate, 3.0%). All three women who became pregnant had unprotected intercourse between Days -1 and 0 and took the ECP on Day +2, based on endocrine data. Day 0 was taken as ovulation day. Among 17 women who had intercourse in the fertile period of the cycle and took the ECP after ovulation occurred (on Days +1 to +2), we could have expected three or four pregnancies; three were observed. Among 34 women who had intercourse on Days -5 to -2 of the fertile period and took ECP before or on the day of ovulation, four pregnancies could have been expected, but none were observed. We found major discrepancies between women's self-report of stage of the cycle and the dating calculation based on endocrine data. These data are supportive of the concept that the LNG ECP has little or no effect on postovulation events but is highly effective when taken before ovulation.
Fehring RJ et al., 2004·Contraception·
Open Access
The purpose of this study was to compare the fertile phase of the menstrual cycle as determined by the Clearplan Easy Fertility Monitor (CPEFM) with self-monitoring of cervical mucus. One-hundred women (mean age = 29.4 years) observed their cervical mucus and monitored their urine for estrogen and luteinizing hormone metabolites with the CPEFM on a daily basis for 2-6 cycles and generated 378 cycles of data; of these, 347 (92%) had a CPEFM peak. The beginning of the fertile window was, on average, day 11.8 (SD = 3.4) by the monitor and day 9.9 (SD = 3.0) by cervical mucus (r = 0.43, p < 0.001). The average first day of peak fertility by the monitor was 16.5 (SD = 3.6) and by cervical mucus 16.3 (SD = 3.7) (r = 0.85, p < 0.001). The mean length of the fertile phase by the monitor was 7.7 days (SD = 3.1) and by cervical mucus 10.9 days (SD = 3.7) (t = 12.7, p < 0.001). The peak in fertility as determined by the monitor and by self-assessment of cervical mucus is similar but the monitor tends to underestimate and self-assessment of cervical mucus tends to overestimate the actual fertile phase.