CHANGES IN THE CERVIX
To use the sympto-thermal method effectively, it is not essential to
check the cervix.
Temperature and mucus observations give a woman adequate information
about her state of fertility. However, some women find that monitoring
changes directly at the cervix gives additional supportive information.
In special circumstances, such as during breast-feeding and the
pre-menopause, it can give valuable early warning signs of approaching
Changes in the cervix are due to the effect of the hormones oestrogen
- During the infertile phases of the cycle,
the cervix is low in the vagina, and easily within reach of the
- It appears to be long and may be off-centre, tilted, to lie against the
- It will feel firm, like the tip of a nose.
- The cervical opening (os) will be closed, giving the sensation of a
dimple to the touch, and it will feel dry.
- As ovulation approaches, the rising oestrogen levels cause the cervix
to rise higher in the vagina.
- It appears shorter, straighter and more centrally positioned in the vagina.
- It may be difficult to reach. It will feel softer, more like the texture
of the lower lip.
- The cervix relaxes slightly allowing the os to open enough to admit the
- It will feel wet and flowing with mucus.
- Following ovulation, the cervix returns to its infertile state
within 24-48 hours.
Changes in the Cervix - in Relation to Ovulation
The changes in the cervix take place over an interval of around ten
Approximately six days before the shift in temperature the cervix will
begin to show fertile characteristics.
Following ovulation, the cervix returns to its infertile state within
The subtle changes in level, position consistency and dilatation of the
cervix occur gradually and may seem confusing at first, but with
experience a woman will be able to recognise at least one of the
characteristics which will give clear indication of her state of
Self-Examination of the Cervix
A woman can detect changes in the cervix by feeling gently with the
fingertip. A delicate touch is all that is required to distinguish the subtle
The cervix should be examined at the same time each day, for example
while washing in the morning, after emptying the bladder. The same
position should be used, either standing with one leg raised
(e.g. on the side of bath), or squatting. If the position is varied then
the cervix will appear to be at a different level.
Some women find it easier to use two fingers, the index and middle fingers
to examine the very subtle changes in the cervix.
- The hands should be washed and dried (the fingernails should be short).
- The right index finger is gently inserted into the vagina until the
cervix can be touched.
It will feel like a smooth indented ball.
The vaginal walls feel soft, moist and ridged in comparison.
- If the cervix is difficult to reach, the uterus may be pushed down by
pressing on the abdomen with the left hand, just above the pubic bone.
With experience this examination should only take a few seconds.
Other women find that their partner is more in tune with these changes
and is so is able to be actively involved and share the responsibility.
It is important that cervical observations are made in the same way, by
the same person. It generally takes two or three cycles for cervical
changes to be interpreted accurately.
Detection of mucus at the cervix
While checking the cervix, some cervical mucus may come away on the
This should be recorded on the chart separately.
- Women who have difficulty distinguishing mucus changes externally or
have a very short mucus build up may find it useful to take mucus
directly from the cervix in this way.
This avoids the delay in transit time from cervix to vulva and gives an
earlier warning of approaching fertility.
- An interval of a day or two may occur before thick, sticky mucus noted
at the cervix is visible externally.
The more liquid, fertile mucus appears at the vulva within hours.
Some women find that mucus becomes trapped in the ridged vaginal walls,
and it appears as a long thread on the finger.