Parameters used in assessing the mucus symptom:

There are two main parameters, i.e. (i) Sensation and (ii) Appearance, used by the woman in assessing the mucus symptom at the vulva (= the external opening of the vagina).

  • SENSATION: This is the sensation associated with the presence of mucus at the vulva, although the mucus may not be visible
  • APPEARANCE: This is what the mucus actually looks like at the vulva, i.e. its colour and texture. (Table 11-1).

If just one of these two recorded parameters of mucus, (i.e. either the sensation or appearance), has a description which in keeping with more-fertile mucus the woman is considered potentially more-fertile.

less-fertile mucus more-fertile mucus
sensation moist, damp at vulva wet, lubricative, slippery at vulva
appearance / texture viscous, scant, opaque, ‘tacky’ abundant, runny, clear, like raw egg-white, elastic, stretchy, ‘spinnbarkeit’

Table 11-1; Mucus Parameters: The changing pattern of the oestrogenic mucus symptom is observed by the woman during the ‘build-up’ to peak mucus in the fertile phase of the cycle, using the two parameters, sensation at the vulva and appearance and texture of mucus at the vulva.

Pictures of the changing pattern of the Mucus ‘Build-Up’ to Peak Day & Ovulation:

LESS-FERTILE MUCUS is associated with a moist or damp sensation at the vulva and the appearance of mucus is thick, opaque, viscid and ‘tacky’, (mucus that breaks on stretching, is called ‘tacky’ and is typical of the less-fertile mucus). Fig.11-4

Fig. 11-4; Less-fertile mucus  –
 is thick, opaque, viscid and breaks on stretching between the fingers, i.e.’tacky’.


MORE-FERTILE MUCUS is associated with a wet, slippery, or lubricative sensation at the vulva, and the appearance of the mucus, is described as cloudy, clear (Figs. 11-5, 11-6), and its texture is described as elastic, stretchy, (Fig.11-7), like raw egg-white, or ‘spinnbarkeit’ (Fig. 11-8). (mucus that holds a stretch up to 10-20 cms is termed ‘spinnbarkeit’ and is the classic appearance of more-fertile mucus).

Fig. 11-5; More-fertile mucus –
is cloudy-clear and is beginning to hold a stretch

Fig. 11-6; More-fertile mucus –
mucus is now clear.

Fig. 11-7; More-fertile mucus –
is now clear and stretchy.

Fig. 11-8; More-fertile mucus –
Spinnbarkeit. Good spinnbarkeit means that the mucus can hold a stretch to 10-20 cms (5 inches).3

Quantity of mucus:

A third parameter namely the Quantity of the mucus is also important in fertility. It is the quantity of cervical mucus that allows for the neutralization of the acidic vagina and subsequent sperm survival.2 The mucus increases in quantity during the latter stages of the mucus ‘build-up’.

There is considerable variation of quantity and quality of cervical mucus and consequently of being aware of fertility when comparing one woman’s experience with another and even in individual cycles of the same woman.1 All women charting their cycles know that the mucus symptom can differ considerably from one cycle to another.1


  1. Odeblad E, ‘Investigations on the physiological basis for fertility awareness; Bulletin for the Ovulation Method Research and Reference Centre of Australia, vol 29, no 1, p2-11, march 2002, (internet, Billings Ovulation Method,
  2. Hilgers TW, Prebil AM; ‘The ovulation Method-Vulvar observations as an index of fertility/infertility’ page 21; Obstetrics & gynaecology, vol 53, no 1, Jan 1979.
  3. Cohen M, Stein I, Kaye B; ‘Spinnbarkeit: ‘A characteristic of cervical mucus; significance at ovulation time’; Fertil & Steril; Vol 3, no 3, 1952.