WOMEN’S BODIES: SIGNS OF FERTILITY. OVUM, CERVICAL MUCUS AND CERVIX.

Posted on Wednesday, March 11th, 2009 at 4:53 pm

The ovum

The ovum m the past it was thought that the ovum I could be fertilised for up to 24 hours after ovulation, but recent research indicates that its survival time is closer to 12 hours. Thus the most favourable condition for fertilisation would be to have sperm waiting in the tube when the ovum is released. We ovulate on one day only of the cycle, even if more than one ovum is released (as happens in cases of non-identical multiple pregnancy). If an ovum isn’t fertilised, it dies and conception is impossible during the rest of the cycle.

Cervical mucus

The characteristics of ‘fertile mucus’ – copious in amount, clear, watery, slippery and stretchy – are at a peak just before ovulation. Soon (within 24 hours) after ovulation, progesterone from the corpus luteum changes the mucus, making it thick and sticky. Cervical mucus influenced by progesterone does not allow sperm to pass through the cervical canal.

The cervix

At the beginning of a cycle the cervix feels firm and its opening into the vagina (external os) feels tightly closed. As ovulation approaches, the cervix feels softer and wider and the os becomes lax enough to admit a fingertip. After ovulation the cervix soon returns to its firm state with a closed os. Some women also notice that their cervix is closer to the vaginal opening at the beginning of the cycle and after ovulation, and further from it during the fertile period before ovulation.

Because changes in the cervix may be hard to compare from day to day, it is recommended that you combine feeling the cervix with observing the cervical mucus and/or keeping a temperature chart.

Body temperature

We have already seen that one of the effects of progesterone from the corpus luteum is to cause a rise of 0.2-0.6°C in basal body temperature.

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