Fertility Awareness Biomarkers

Cervical mucus and identification of the fertile phase of the menstrual cycle

Flynn AM, Lynch SS

Published August 1976 British Journal of Obstetrics and Gynaecology, 83(8), 656-659
DOI 10.1111/j.1471-0528.1976.tb00906.x PMID 952797

RRM Academy Synopsis

Nine fertile women predicted ovulation by grading their cervical mucus

Nine healthy women who graded their own cervical mucus identified the fertile phase of their cycle, a 1976 Birmingham study of 29 cycles found. Any mucus appeared on average 5.2 days before the LH peak. The study took the LH peak as the day of ovulation.

Study at a glance: Women graded their own cervical mucus to identify the fertile phase
Study at a glance: Women graded their own cervical mucus to identify the fertile phase. Source: Flynn AM et al., 1976, PMID 952797.

Key Findings

  • Nine healthy women, aged 26 to 44, were followed through 29 menstrual cycles, and an LH peak was observed in all 29 cycles.
  • Basal body temperature showed a biphasic pattern in 26 of the 29 cycles; the other 3 cycles had missing or insufficient temperature readings.
  • Any mucus first appeared on average 5.2 days before the LH peak.
  • In 8 of the 29 cycles, in five women, the fertile mucus phase before ovulation lasted only two days.
  • The women identified cervical mucus in the 29 cycles, and grading became easier with continued observation.

Interpretation

This study followed nine healthy, fertile women, each with three to six children, through 29 menstrual cycles. The women graded their own cervical mucus and charted body temperature. Blood tests tracked LH, estradiol, and progesterone as the hormone reference. The women identified the fertile phase in every cycle. Semen after intercourse caused some confusion early on, but grading got easier with practice. Social status made no difference: women in lower social grades did just as well, or better. The authors think the method could help infertile women recognize ovulation without long, costly hormone testing. The findings support larger studies of mucus charting in women trying to conceive.

RRM Context

Restorative reproductive medicine reads the cycle as a sign of how the body is working. The women here tracked cervical mucus along with body temperature. Symptothermal methods pair these two signs to mark the fertile window. Blood tests served as the reference here. A woman can track her own mucus with no blood draw. Charting gives a couple a shared record of the fertile window.

Abstract

Nine healthy fertile women were studied during 29 menstrual cycles. A cervical mucus grading system, assessed by the patient and used in conjunction with basal body temperature, was correlated with plasma levels of luteinizing hormone (LH), oestradiol and plasma progesterone. The results show that a patient can be taught to predict the time of ovulation by observing the changes in the cervical mucus.

Topics

By this author

Related research

Fertility Awareness › Biomarkers › Cervical Mucus · Menstrual Cycle › Cycle Biomarkers › Cervical Mucus · Reproductive Endocrinology › Ovulation Physiology › Follicular Development
Anna M. Flynn
A Flynn
PMID 952797 952797 DOI 10.1111/j.1471-0528.1976.tb00906.x 10.1111/j.1471-0528.1976.tb00906.x Flynn et al. 1976, Flynn 1976