How to Plan Your Fertility Calendar

Is having children next on your list? If yes, do you know when is the perfect time to get intimate? Keeping up with dates can be a hassle especially if both of you and your partner have bustling lives. Consider yourselves lucky, because we’re going to tackle the puzzle of fertility calendars. 

Understanding menstrual cycles

Before jumping into calculating your fertile days, let’s run through the four main phases of the menstrual cycle:


This is the phase where you will be having your period and it usually lasts for five days. When pregnancy does not occur, the lining of your uterus will be shed through your vagina and you’ll start menstruating.


The follicular phase is when the egg (ovum) matures in anticipation of the ovulation phase. It begins eight days after the menstruation phase.

The estrogen hormone level rises and causes the lining of your uterus to grow and thicken. This process is important to prepare your womb for pregnancy. Simultaneously. the follicle-stimulating hormone that helps form a fully mature ovum begins to increase. This usually happens between day 10 and day 14.


The ovulation phase is when the ovary releases an ovum. On average, it occurs on day 14.

Once the egg is released, it travels to the fallopian tube where it meets the sperm and fertilisation occurs. In the case of a successful fertilisation process, the egg will travel to the womb and attach itself to the lining of the uterus. Successful implantation indicates healthy pregnancy.


The luteal phase is when the implanted egg develops and secretes estrogen and progesterone that thickens the uterine lining. This phase lasts from day 15 to day 28. If the egg is not fertilised by the sperm, your hormone levels drop and the cycle starts again with menstruation.

Typically after sexual intercourse, the sperm lasts for three to five days in the woman’s body. So, your chances of getting pregnant are bright during the six to seven-day fertile window:

  • Five days before ovulation.
  • On the ovulation day.
  • One day after the egg is released.

Identifying your fertile windows

Menstrual cycles can sometimes be irregular. When it comes to fertile windows, timing is everything. Luckily, there are several ways to find out your ovulation day:


Cervical mucus

When nearing ovulation, the secretions near the cervix or the cervical mucus become wetter, stickier, and clear. It usually changes from a watery texture to a raw egg-white texture. This makes sex smoother and aids the sperm to swim towards the reproductive system easily.

Basal Body Temperature (BBT)

BBT is the body’s lowest resting temperature, which can be measured as soon as you wake up in the morning. After ovulation, your body temperature rises and stays up for a few days. You can predict your next ovulation by recording your body temperature with a fertility thermometer at the same time every day.

Increase in sex drive

The desire for sexual intercourse often increases before ovulation due to the changes in hormones. This can also help you to identify your fertile days.


Also known as implantation bleeding, you may find light bleeding from your vagina that is not because of your monthly menstrual cycle. Spotting indicates that an embryo has implanted in the lining of your uterus and it usually takes place about 10 days after conception.

Breast tenderness

Estrogen, progesterone and prolactin (the brain hormone associated with lactation) hormones boost blood flow to the breasts in preparation for breastfeeding. This results in changes in breast tissues and sore and tender breasts and nipples.

Heightened sense of smell

Thanks to the surge in estrogen, you gain super-smelling powers too. 

Mild pelvic pain

This sign could be attributed to a stretching uterus or hormonal changes in the body.

Ovulation calculator

If keeping track of body changes is hard, you can opt for an ovulation calculator or a fertility calculator. Here are some figures to take note of when using this tool:

The first date of your last menstrual cycle

If your period started on the 22nd of August and ended on the 27th of August, the first day of your last menstrual cycle is on the 22nd.

Your average menstrual cycle length

Your cycle length is the duration between your last menstruation to your current menstruation. So take the first day of your last period and the first day of your current period. For example, if your previous period started on the 22nd of August and your next period starts on the 20th of September, your menstrual cycle is 29 days.

You can also calculate the average of your cycle in the past 3 months. For example, if it is 30, 29 and 28 days, your average cycle length is 29 days.

Rhythm method

The rhythm method, also known as the calendar method or calendar rhythm method is a natural family planning method. 

To use the rhythm method, you must track your menstrual cycle to predict when you’ll ovulate. If you’re hoping to get pregnant, this method can show you the best days to have sex. Conversely, it can also tell you when to avoid sex or use contraception if you’re hoping to not get pregnant.

The rhythm method is an inexpensive and safe way to help you chart your fertility. However, it is considered one of the least effective forms of birth control. The efficacy of this method varies between couples. Do remember that the rhythm method doesn’t protect you from sexually transmitted infections.

Baby-making can be a stressful period for some. You may get too calculative with time and before you know it, you’ll be clutching calendars in your sleep. Give yourself and your partner some space to care for each other and be present in the moment. 

Besides keeping track of your fertility calendars, practice some of these tips with your partner for a blissful journey:

Maintain a healthy weight

Exercising and staying fit are essential to boosting your health and facilitating a smooth menstrual cycle.


Committing to some relaxing couples activities like yoga, meditation and long strolls in the park are great opportunities for both of you to get some one-to-one time.

Manage medical conditions

If you have medical conditions like diabetes, asthma, or epilepsy, be sure it is under control. Speak to a fertility doctor to know more about your health and what you can do about it.

We hope fertility calendars come easy for you and your partner now. What are you waiting for? Get counting, mark your calendar and have some fun!

Sources: parenTeam Malaysia, KL Fertility Centre, Dr Gan Penang, Cleveland Clinic, WebMD, Mayoclinic, Parents