Trying to Conceive


You’ve made the big decision to start a family and now you are trying to conceive. You’ve read our advice on Preparing for Pregnancy and Reproductive Carrier Screening. You’ve had a pre-pregnancy planning appointment. So how do you give yourself the best chance of actually falling pregnant?

What has to happen to fall pregnant?

In the simplest of terms, an egg must be fertilized by a sperm. But for this to happen and lead to a successful pregnancy, a lot of things need to line up. Let’s go back and review some basic biology.

The menstrual cycle

Your menstrual cycle is the time from the first day of one period to the first day of the next period. The average menstrual cycle is 28 days, but it’s possible for your cycle to be anything from 21 – 35 days. However, your cycle should be regular (the number of days should be the same from month to month). An irregular cycle can be a sign of underlying medical problems.

Day 1 of your cycle is the first day of bleeding.

The menstrual cycle includes:

  • The follicular phase. The lining of the uterus starts to thicken and prepare for a possible pregnancy. The ovary gets ready to release an egg.
  • Ovulation. See below for more details.
  • The luteal phase. The egg travels towards the womb. Hormones keep the uterus ready to receive a fertilized egg.
  • If no pregnancy occurs, the uterus sheds its lining. This is your period. Then the whole cycle starts again.


Your ovaries produce eggs as well as hormones that are critical to reproduction. You have two ovaries, one on each side of your pelvis.

Each month, one of your ovaries releases an egg (ovulation). The egg travels down the Fallopian tube, heading for the womb. If the egg meets a sperm, it may become fertilized – the egg and sperm fuse together and start creating the new cells that will eventually develop into a baby. In successful pregnancies, this ball of new cells travels all the way to the womb and implants into the lining.

Not all women ovulate each month. Medical conditions such as polycystic ovarian syndrome (PCOS) and endometriosis can interfere with ovulation. The simplest sign of ovulation is a regular menstrual cycle. If your cycle is irregular, see your GP or obstetrician for further investigation.

Uterus diagram

Cycle tracking when you’re trying to conceive

Tracking your menstrual cycle can be really helpful when trying to conceive. Start a period diary. This can be as simple as marking each day of bleeding on a paper calendar. There are also a host of period-tracking apps available.

After a few months, you will be able to see how long your cycle takes and if it is regular. If it’s regular, you will be able to estimate the time of the month when you ovulate. If your cycle is irregular, you won’t be able to do this reliably and you should see a doctor for help.

Ovulation occurs approximately 14 days before the next period starts. If you have a regular cycle and know when your next period is due, count back 14 days from that date. The day you land on is the approximate day you expect to ovulate.

There are other ways to identify when you are ovulating:

Urine ovulation test kits

These work by detecting luteinizing hormone (LH) in your urine. LH increases just prior to ovulation.

Kits can be purchased at most pharmacies. It’s better to buy one from your local pharmacy as products sold in Australia must meet certain standards. Kits purchased online may not be subject to the same standards.

These kits are expensive to use long-term and aren’t totally reliable. They also won’t tell you anything about underlying causes of infertility. If you’re trying to conceive, use the kits as part of a plan from your doctor, not in place of medical advice.

Basal body temperature monitoring

This requires a special basal thermometer. Check your temperature as soon as you wake, while you are still in bed. You will notice a small rise in your baseline temperature that starts after ovulation and continues until your period.

Over the course of a few months, you should be able to identify a pattern in your cycle. If there is a pattern, you may be able to predict when you will ovulate. This is quite a difficult technique to use correctly and the full instructions are more detailed than can be described here.

Changes in cervical position and mucous

You can feel your own cervix by inserting a clean finger into your vagina. Most of the time the cervix will be low down and feel firm. Around the time of ovulation, it may feel higher up and softer. At the same time, your normal vaginal discharge will look and feel a bit like egg white (thin and stretchy).

If you examine yourself regularly you may be able to detect these changes. In practice, however, it is often difficult for women to detect these changes reliably.

The Fertile Window and Timed Intercourse

Pregnancy is most likely if you have sex 1-2 days prior to ovulation. The easiest way to achieve this is simply to have unprotected sex every couple of days between periods. However, this may not be possible or practical for a number of reasons.

If you have a regular cycle, you can calculate the window of time where you are most likely to conceive. This is called the fertile window.

Identify your likely day of ovulation by counting back 14 days from your next period. The fertile window is the five days before ovulation, plus the day of ovulation. Make sure you are having sex every second day in this window.

This isn’t an exact science. Ovulation can actually occur between 10 and 16 days before your period. Sperm can survive in the womb and Fallopian tubes for 2 to 3 days. (The egg has a much shorter lifespan; once ovulation occurs, it needs to be fertilized within 12 – 24 hours). So if you’ve been trying to conceive for a few months without success, consider expanding the window during which you are having regular intercourse.

Let your partner know that regular ejaculation (every 2-3 days) will improve the quality of his sperm. However, ejaculating every day may have the opposite effect.

Trying to conceive without success? When to seek help.

We expect 80-90% of healthy couples to fall pregnant within 1 year of starting regular, unprotected intercourse. But if you don’t fall pregnant, it’s important to know when to seek medical advice.

See a doctor if:

  • You are under 35 years old and have been trying for 12 months
  • You are over 35 years old and have been trying for 6 months. Older women typically have fewer good quality eggs, so we investigate and treat subfertility sooner in this age group.

Sometimes, it’s better to act even sooner. See a doctor as soon as possible if:

  • You have an irregular cycle. This is a good indicator of potential underlying medical issues such as PCOS.
  • You are unable to have intercourse successfully. This can occur for several reasons. Patients with conditions such as endometriosis may experience severe pain that prevents intercourse. Vaginismus is a condition where the vaginal muscles spasm, interrupting sex. Erectile dysfunction is a common issue for men.

As always, this information is intended for general educational purposes only. It is not medical advice. Please discuss any medical issues with your own doctor. Read our full medical disclaimer here.