• Once an egg is released, it remains viable for around a day. Allow a day or so on either side of this for minor variations in the time of ovulation. Sperm can remain viable in the woman’s body for around two days.
• Therefore, the fertile time is estimated as being from two to three days before to two days after the estimated time of ovulation. This is the best time to try to conceive.
Some women know when they are ovulating because they feel lower abdominal pain at the time when the egg is released from the ovary. The pain is quite normal and is referred to as ‘Mittelschmerz’ (from German words for ‘middle’ and ‘pain’ – hence pain felt mid-cycle).
It’s time to conceive
Many women wonder if they need to see their doctor for a health assessment before they conceive. However, no specific check-up is usually necessary if you are healthy, have no history of miscarriage, pregnancy complications or of a long-standing medical condition.
Stopping using contraception
If you have been using a form of contraception to prevent pregnancy, depending on what method this is, the length of time it might then take you to become pregnant is affected. Barrier methods do not disturb ovulation or the menstrual cycle and you can simply stop at any time. There is no need to delay attempts to conceive provided there are no other menstrual or medical problems.
must know
Smear test
Check that your cervical smear tests are up to date before conceiving. If you need treatment for an abnormal smear, this should, ideally, be carried out before you get pregnant.
If you use an intrauterine contraceptive device, or ‘coil’, for contraception then this must be removed before you try to conceive. It is probably best to delay conception until at least the next cycle as the coil may have disturbed the lining of the womb. So, after the doctor has removed the coil, you should use another technique, such as barrier contraception, until you are ready to conceive.
If you use the oral contraceptive pill or an injectable contraceptive, your normal menstrual cycle and ovulation is disrupted. The time from stopping the pill to ovulating is extremely variable. Estimates of the time of ovulation are based on the date when the next natural (not pill-induced) period is expected, so it is impossible to estimate when ovulation will occur after stopping the pill.
If you wish to get pregnant, it is best to stop taking the pill or injectable contraceptive and wait until your normal menstrual cycle resumes before trying to conceive. As this may take about three normal menstrual periods, you might want to use a technique such as barrier contraception until your cycle has stabilized. If you become pregnant before the regular rhythm of your periods has become established, this can make it difficult to predict your delivery date based on your last period. However, a reliable estimate of the stage of the pregnancy can be obtained with an ultrasound scan to measure the size of the developing baby.
did you know?
Temperature change
• The typical change seen before ovulation would be a body temperature of 36.6-36.8 °C (97.9-98.2 °F), which falls to 36.2-36.4 °C (97.2-97.5 °F).
• The temperature would then increase to, say, 37-37.1 °C (98.6-98.8 °F) by around 36 hours after ovulation.
• If you regularly chart your temperature, you will see a pattern developing.
Using your body temperature to predict ovulation
Your body temperature should fall slightly before ovulation then rise quickly afterwards. It is worth noting, however, that sometimes the fall prior to ovulation is absent. The increase in temperature occurs in response to the progesterone that is produced after ovulation occurs. Progesterone levels and the body temperature remain elevated until a day or so before the next period begins. If pregnancy occurs, the temperature rise (and elevated progesterone levels) persists.
• If you want to use this technique to find out when you are ovulating, take your temperature with a thermometer in the morning before getting out of bed. Any medical thermometer that can measure in tenths of 1 °C can be used. Thermometers (including electronic ones) and temperature charts can be purchased from pharmacies.
• If you are recording an oral temperature reading, remember to check your temperature before drinking anything hot or cold to avoid getting an inaccurate reading.
• Take your temperature at the same time every day.
• Repeat for each cycle that you want to check for ovulation. If you have a regular cycle, ovulation is likely to occur at around the same time during each cycle.
The downside of using this method to check for your fertile period is that your temperature rise occurs after ovulation and by the time your temperature has risen, the egg may no longer be viable. If you have a regular menstrual cycle, however, the time of ovulation may be anticipated based on a well-recorded pattern in temperature rise. This then allows intercourse to be timed to coincide with ovulation.
Consistency of vaginal mucous
The consistency of vaginal mucous can help predict the fertile phase as the character of the discharge varies through the menstrual cycle. Just after a period, it is scant, sticky and thick. Just before the time of ovulation, when oestrogen levels are high, the amount of mucous increases and it becomes watery, stringy and clear – a bit like raw egg white.
If you collect the mucous on your finger at this time and try to stretch it between your thumb and forefinger, it elongates for several inches without breaking. After the fertile phase, the mucous again becomes thicker. Sperm can survive particularly well in the thinner ‘fertile’ mucous, which also makes it easier for the sperm to get through the cervix and into the womb. So charting the pattern of changes in your vaginal mucous can also help you work out when you are ovulating.
Ovulation prediction kit
If you want to know when you are likely to be most fertile, you could buy an ovulation prediction kit. These kits, which are available from pharmacies, measure the amount of luteinising hormone (LH) – the hormone that stimulates the release of eggs from your ovaries each month – in your urine.
The kit identifies a surge in this hormone, which precedes ovulation by around twelve hours. This can help establish the fertile days in your cycle. Ovulation prediction kits are more accurate than temperature charts and avoid the need for regular temperature assessment, but they are also more expensive.
Frequency of intercourse
However, even with temperature charts or ovulation prediction kits, it is often difficult to identify the precise time of ovulation in advance. So, from a practical perspective, you should have intercourse several times around the estimated time of ovulation. Doctors have found that having intercourse once a week makes you 50 per cent less likely to conceive than having it every couple of days. Success rates do not appear to get significantly higher if you have sex every day. Sperm survives in the woman and is capable of fertilizing an egg for around two days after intercourse, especially during her most fertile time. In addition, there is no need to restrict intercourse at other times of the month. Indeed, the best plan is to have intercourse regularly every couple of days throughout the cycle. This avoids putting pressure on you both to identify the fertile time, obliging you to make love according to the calendar rather than by desire.
Sperm production
It is the same gonadotrophins that occur in women (follicle-stimulating