Can you predict the baby's sex using the lunar calendar?

Can you predict the baby's sex using the lunar calendar?

You're pregnant and can't wait to find out the sex of your baby? There's no need to wait for the 3rd-month ultrasound to find out whether you'll have a baby boy or a baby girl, as there are many ancestral methods for predicting your baby's sex... Among them: the lunar calendar. But is it a reliable method? We explain!

Use the lunar calendar to predict the sex of your unborn child

At a time when the lunar calendar700 years ago, there were no medical means available to predict the sex of babies. One of the techniques used at the time was theobservation of the stars, in particular the moon.

This calendar is based on two factors that predict the sex of the baby at the moment of ovulation. These two factors are :

  • Moon phases, i.e. waxing or waning moon;
  • And the mother's age at conception.

The moon calendar is thus represented as a table with two axes: one for the 12 months of the year and the other for the woman's age. To find out the baby's sex, you'd need to cross-reference the coordinates of the two axes in the table. Warning: this method cannot predict the birth of twins of opposite sexes.

If the lunar calendar is one of the methods used to determine a baby's sex, it's also because there's still a belief that the menstrual cycle is controlled by the movements of the moon, or the moon cycle. In fact, the average menstrual cycle lasts 28 days, roughly the same as the lunar cycle. The periods correspond to the new moon. It is also believed that women's ability to conceive a child is greater during full moons and the days preceding them.

Is the lunar calendar 100% reliable for boys and girls?

Some women would still use this method today to determine the month in which they wish to become pregnant, depending on whether they prefer to have a boy or a girl.

Please note, however, that no scientific study has validated this method of predicting a baby's sex. In fact, the probability of the predictions being true is one in two, so it's pretty easy to believe them.

According to science, it is not possible to predict the sex of the baby, since this depends on the chromosome contained in the sperm. Two XX chromosomes make a girl, and X and Y chromosomes make a boy. However, there's nothing to stop you from testing for yourself and seeing if the prediction you get is right!

How to have a male baby according to the Moon?

According to beliefs and the lunar calendar, a boy can be conceived during the waning moon phase. Conception must occur between the full moon and the new moon, i.e. when the first or last quarter of the moon is visible.

The other phases of the waning moon are the waning gibbous moon, the last crescent, the last quarter and the new moon.

How to have a female baby according to the Moon?

On the other hand, if you want to have a girl, it's best to conceive during the ascending moon phase l. The ascending moon phase is made up of several periods:

  • The first crescent moon;
  • First quarter (when the moon is in a semicircle) ;
  • The waxing gibbous moon;
  • The full moon.

The lunar calendar and baby sex FAQ

How can I tell if it's a boy?

There are several other ways to determine the sex of your baby. If the mother's belly is rather pointed and high, we would tend to say that s'it's a boy. If the pregnant woman has no nausea, this again would mean that s'it's a boy. If your cravings during pregnancy are rather salty, then s'we're talking about a boy.

How do you know it's a girl?

As with s'it s'is a boy, there are other methods for determining s'it s'is a girl. Some say that if the pregnant woman's belly is rather rounded and low, it s'would be a girl. If you're prone to a lot of nausea and cravings for sweets, then again, you could be pregnant with a girl!

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The information contained in the articles on is general information only. Although reviewed by health professionals, this information is not error-free, does not constitute health advice or consultation, and is not intended to provide a diagnosis or suggest a course of treatment. Under no circumstances may this information be used as a substitute for medical advice or consultation with a healthcare professional. If you have any questions, please consult your doctor.