Pregnancy and Ovulation Calculator

It can be very helpful for women to know when they are likely to ovulate. As a means of building more awareness of how their body works or as a tool to help maximise the chances of conceiving, becoming ovulation aware is a good skill to have. After all, over the course of a woman’s reproductive lifetime, ovulation can occur as many as 460 times, so there is plenty of opportunity to practice.

Predicting ovulation can also be used to avoid conception, but bear in mind even women who are highly tuned into their body’s cycles can miss the signs that ovulation is imminent. Far from being exact, ovulation prediction weighs up the odds and at best provides a reasonably accurate idea. This is why most ovulation predictors come with a covering disclaimer – there are no guarantees. Most are described as a “best guess”, harmless means of boosting the odds of falling pregnant.

Our easy-to-use ovulation calculator will help you predict your prime time for conceiving a baby. Learn about the different phases of your ovulation cycle, how your temperature can alert you to ovulation time, and many other interesting and useful facts and figures. The calculator is a great tool – especially when used while watching for your signs of ovulation.

Please enter the relevant dates below and click calculate.

Note to use this calculator, you will need the latest version of Flash installed on your computer. The calculator provides an estimate based on the information you provide and may not be accurate. Please seek advice from a medical professional if you are trying to conceive.

How Can I Tell If I’ve Ovulated?

Each month an egg is supported towards maturity by the action of hormones on the ovarian follicle in which it rests. Generally a new egg ruptures and is released mid-cycle; around day 14-15 after the first day of the last normal period. If the egg is fertilised and implants in the uterus, there will be no period. However, if fertilisation does not occur then the uterine lining is shed in the next period, around 14 days later.

The most common and basic method of detecting ovulation is to use a monthly calendar. Mark the first day of your menstrual period and again, when bleeding stops. Doing this for a couple of months will help you to understand your own biological patterns and the cyclic, generally predictable nature of menstruation. Although the average length of a menstrual cycle is 28 days, this can vary between individual women. Some have shorter or longer cycles. It is important to look for physical changes which indicate ovulation has occurred, rather than rely solely on calendar dates.

When Should We Try?

Having intercourse just prior to, or at the time of ovulation will maximise the chances of conceiving a baby. There is only a small window of time – twelve to twenty four hours, where the egg is viable and capable of being fertilised. Sperm are much more robust than eggs and can survive for between three to six days after ejaculation. Fertilisation normally occurs in one of the woman’s fallopian tubes. As soon as the egg has been fertilised, a signal is given off to the other sperm not to waste their efforts, there has already been a lucky winner.

For more information see conception and getting pregnant

Physical Signs of Ovulation

• An increase in the woman’s body temperature. Taking the basal body temperature first thing in the morning can be a good way to detect when ovulation has occurred. Progesterone causes a rise in temperature to around ½ a degree and over a few months, it can be possible to see a pattern of slight elevation in the second half of a monthly cycle when compared to the first half. A special basal body thermometer is needed for accuracy.
• A change in the cervical mucous. Infertile mucous is scant in quantity, clumpier and appears milkier; fertile mucous looks very different. It tends to be clear, watery and more stretchy– all designed by nature to support those little sperm to swim more smoothly up through the cervix and towards the fallopian tubes.
• Some women experience mild cramping or discomfort in the region of their ovaries when they are about to ovulate. Others will feel vaguely nauseous, have back ache or headache. Some may even have a very slight blood stained vaginal discharge.
• An increase in libido. Science has proven that women genuinely seem prettier and more attractive to their partners when they are about to ovulate. Even their body language can change in the most subtle of ways.
• Using an ovulation testing kit which comes in one of two forms – saliva testing or urine based. Saliva testing can be useful as it predicts a surge in oestrogen just before ovulation occurs. Urine test kits work by identifying a rise in luteinising hormone which occurs one or two days before ovulation happens. Both testing kit varieties are available from pharmacies and are a straightforward way to help couples identify when conception would be most likely.
• Breast tenderness, feeling cranky and not as even tempered, abdominal bloating or even tummy upsets are common in women who are ovulating.

Ovulation Calculator

When using an ovulation calculator it is also possible to estimate possible conception dates. For couples who are keen to fall pregnant or who need to coordinate the time when they can get together, ovulation calculators can be very useful for planning purposes.

Advantages of Using an Ovulation Calculator

• Planning for sex to coincide with ovulation. This maximises the chances of conceiving when a couple chooses to.
• As a means of contraception and reducing the likelihood of conceiving. For religious, cultural or family planning reasons, using a calculator can be a non-invasive method of “natural” family planning.
• For couples who spend time apart and are not always in close enough proximity to support spontaneous sex, the chances of conceiving are reduced. Using an ovulation calculator gives some framework to plan around dates and most fertile days.
• Useful in terms of predicting when the next menstrual period is due. For recreational reasons, working, going away and general comfort, being able to do this is often useful.
• For couples who want to have more onus of control over their fertility, make decisions around planning which suits them and maintain some privacy, ovulation calculators are another option.

Due Date Calculators

Most pregnancy calculators work by estimating the baby’s due date as being 280 days from the first day of the last normal period, or by adding nine months and seven days to this date. Ultrasounds have become a routine means of providing an accurate assessment of foetal maturity.