P Mucus (oestrogenic)

P mucus was first identified in 1990.6 P mucus is secreted in the upper part of the cervical canal,3,5 and nor adrenaline and oestrogen stimulate the secretion of P mucus.1 P mucus has a number of subtypes but the most important are called P2 and P6. P mucus has two functions; (i) P2 has a mucolytic action (dissolves mucus), and (ii) P6 has the capacity to conduct sperm cells from the S crypts to the uterine cavity.

  • (i) P2 Mucus: P2 mucus is secreted in the crypts in the upper half of the cervix5 and is at its maximum at the beginning of the fertile phase (4-8 days before ovulation).2 It has mucolytic activity, and its physiological role may be to liquefy the G mucus to give space for the L mucus, and to liquefy the L mucus to facilitate the S mucus flow which is necessary for sperm propagation to the crypts. After the sperm has resided in the S crypts, mucolysis may help to liquefy the L mucus now blocking the crypt outlets, so that sperm can continue upwards.2,4
  • (ii) P6 Mucus: P6 mucus is secreted in the upper one-sixth of the cervical canal at its junction with the body of the uterus, (isthmus).3,5 P6 begins to appear in rising quantity at the end of the fertile phase mainly at and shortly after ovulation and it conducts sperm cells from the S crypts to the uterine cavity.4 P6 mucus is present on maximum amount on peak day and its presence is associated with the sensation described as extremely lubricative and slippery.2 The S mucus seldom reaches 35% and the P6 mucus seldom reaches more than 10%, but still changes the quality of sensation to an extremely slippery and lubricative sensation. A contributary factor to this sensation is probably an increase of the mucolytic activity. Mucolysis may in some cases be excessive. This results in a loss of continuity of mucus, the vaginal outflow becomes watery and loss of slipperiness and lubrication occurs.2


  1. Klaus, Hanna; ‘Natural family planning – Is it scientific? Is it effective?’ see page 4; Newman Lecture Series 1 -May 21, 2000. ( online).
  2. Odeblad Erik; ‘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, www.woomb.org)
  3. Menarguez M, Pastor LM, Odeblad, E. 2003; ‘Morphological characterization of different human cervical mucus types using light and scanning electron microscopy; Human Reproduction; Vol. 18 No 9, 1782-1789, Sept 2003; available on the internet if you google Erik Odeblad).
  4. Hume K, ‘The biology of the cervix 1998; (internet, google bDr Kevin Hume, cervical mucus’)
  5. Odeblad Erik; ‘Cervical mucus and their functions’;Review article, J of the Irish Colleges of Physicians and Surgeons, Vol 26, No1, Jan 1997 p27-32
  6. Odeblad, E; ‘The discovery of different types of cervical mucus and the Billings Ovulation Method’ page 10, 11, 14, 15, 18 ; Bulletin of the Ovulation Method Research and Reference Centre of Australia, Vol 21, No3; 3-35; Sept 1994. ( google ‘Erik Odeblad, cervical mucus’.)