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monitoring monthly cycles
Timing is everything for anyone trying to become pregnant. A woman can only become pregnant on a few days in every month, so it is important to know when these are.
how a woman's cycle works
An average monthly cycle lasts 28 days. Taking this as a starting point:
Day 1 | The day that a woman's period begins. |
Day 14 | The day that a woman ovulates - in other words, releases an egg. This is when a woman is at her most fertile. |
24 hours | The length of time that an egg cell is viable - can be fertilised - after ovulation. |
Cycle | The day on which a woman's period starts to the day before her next period starts. |
Not all women have a 28-day cycle. It is a good idea to note the precise duration of your cycle. If the duration varies markedly from month to month, it is important to ask your GP to investigate the cause of this.
predict ovulation
Knowing precisely when a woman releases an egg (ovulates) is the first step to improving the chances of pregnancy. Ovulation can occur on day 14, but it may be a few days earlier or later, or it may not happen at all. As a general rule, it usually takes 14 days from the day of ovulation to the day that the new cycle begins. That means if a woman has a 30-day cycle rather than a 28-day cycle, she may ovulate on day 16 rather than day 14.
other facts around timing
To become pregnant, a woman must have intercourse when she is at her most fertile and ejaculation must take place in the vagina. Given that a woman may not ovulate exactly on day 14, it therefore makes sense to have intercourse on days 10, 12, 14 and 16. Intercourse is recommended every other day rather than every day around ovulation to ensure that enough sperm is available. This advice is given because, in men with a low sperm count, daily intercourse can reduce the count even further actually reducing the chances of fertilisation. Moreover having intercourse every other day will not mean you “miss “out because sperm lives for 48 hours after intercourse, even though the egg has to be fertilised within 24 hours. (The cervical mucus also operates as a sort of buffer ensuring that the sperm deposited in the vagina during intercourse passes through it gradually rather than all at once.)
Conversely, it is not necessarily better for men to keep the sperm ‘on hold’ before trying to get your partner pregnant. Two days of abstinence before an attempt to get pregnant will ensure a good quantity of mobile sperm in a fertile man.
An important point to remember is that, if a woman appears to ovulate on “day 14” in one month, this does not necessarily mean that she will do so in the next cycle.
Some women can tell when they are ovulating as a result of changes in their body - cramps in the abdomen and/or a very clear, distinct, stringy vaginal discharge (from the cervical mucus) are general predictive factors. Various aids such as ovulation predictor kits or basal body-temperature thermometers are available, which can also be used by women to accurately predict their most fertile time.
Women are also advised not to use douches or lubricants immediately before intercourse in order to improve the chances of fertilisation.
