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Fertility and the Moon

Fertility and the Moon

Dr Eugen Jonas’ Lunar Method

Every woman needs to know about Dr Eugen Jonas’ Lunar Method and Fertility Calculator!

As a nurse, I always was aware of our hormonal cycle. However, later I found out that we have another fertility cycle running parallel. In other words, we can be fertile twice a month, and it can happen even on ‘impossible days’. How?

Please read on and find out more:

When in the 1950s abortion laws were hotly discussed and introduced, first in Russia and then in Hungary,  women and the medical community were still left with the dilemma of the physical, mental and emotional repercussions of the law permitting this procedure.

As a young doctor, in Nitra Slovakia, Eugen Jonas started to look at this challenge differently. His mission was: ‘How to prevent/ plan pregnancy and avoid this undesirable procedure altogether?’

Traditionally doctors were aware of the effect the Moon has on the fertility cycle in females, and Dr Jonas study began with the Babylonian saying, “Woman is only fertile during a certain phase of the Moon.”

His research leads him to develop a specific calculation method which he tested on family and friends. He observed and collected data over several years and found it was supporting his ideas.

Jiri Malek, a gynecologist in Prague, was the first to show scientific interest in Dr Jonas thesis and invited him to the Maternity Clinic in Bratislava. Here he could do more research and proof his method at the hospital. And again, his findings confirmed his discoveries.

The medical profession began to show interest and invited Dr Jonas to talk all over the world. Next, his work was nearly lost to the west during the communist government. Dr Jonas, however, continued his research behind the iron curtain and found many coherences and connections between the Moon and the female fertility cycle.

He discovered that using the first day of the last period to calculate the delivery date is rarely correct. This calculation based on the hormonal cycle of the woman, and it is still used by the medical profession today.
Dr Jonas calculated the conception date by using the position and phase of the Moon at birth in the female chart. He found that the fertile days are just the three days before the Moon is at the same phase as it was at her birth. He used this method to calculate the conception day and from there, the possible delivery date of the baby.
Dr Jonas also found that the child’s gender depends on the gender of the (tropical) sign the Moon is in during conception. While male signs like Aries, Leo and Libra etc. seem to produce more baby boys, female signs like Taurus, Cancer, Scorpio, turn out more baby girls.

Dr Jonas developed ‘The Lunar Method’ over many years research and claimed a 97% accuracy in determining the

  • Fertility Cycle: This knowledge is useful for conception and contraception!
  • Gender of a child conceived:

Once you determine which days are best for conceiving, you must have or avoid intercourse the three days preceding the chosen days for conception.

There are other factors too; however, being aware of these facts and possibilities is very empowering for any girl and woman. It gives women the knowledge and chance to conceive more consciously and can saves us much heartache.

Here are some links for further reading and a calculator to find out your particular dates:

Many Moon Blessings,


Find out how the Moon affects other areas in your life:

Moontime Blog

Moontime Diary E Jonas

Dr Eugen Jonas’ Lunar Method

Dr Eugen Jonas’ Lunar Method Every woman needs to know about Dr Eugen Jonas’ Lunar Method and Fertility Calculator!!! As a nurse I always was aware of our hormonal cycle, however I found out the practical way that we have another fertility cycle running parallel. In other words, we can be fertile twice

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Iris Detenhoff has been publishing Moontime Diaries since 2006.

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