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Updated: Mar 19

It’s a little know fact that according to astrology women can be fertile more than once a month. That may be great news for women trying to conceive but slightly alarming for those trying to avoid falling pregnant, so it pays to understand how the female fertility cycle relates to the lunar cycle.

Iris Detenhoff is the author and publisher of ‘The Moontime Diary – a yearly almanac designed help us live, work and love in tune with the moon and stars. A trained nurse, Iris has also studied natural health, astrology, sustainable building, the teachings of Rudolf Steiner, and the lunar method of contraception and fertility developed by Dr. Eugen Jonas.

As a nurse I always was aware of our hormonal cycle influenced our fertility, but it wasn’t until I studied astrology that I learnt we can be fertile twice a month and can fall pregnant even on days when it should be ‘impossible’, she says.

The 28-day female hormonal cycle mimics that of the moon’s 27.5-day cycle. Our monthly cycle begins on the first day of our period. This is akin to the new moon. In the same way that the moon has a waxing period leading up to the full moon, so too does our body. During the first 14 days of our cycle, our body is preparing the womb with the mucous membranes to support the egg (ovum), which is released during ovulation around the 14th day of our cycle. This is the time of the month when we are fertile and can potentially fall pregnant.

At that time, if you compare this with the full moon, you can say that energy has been absorbed, moisture has been retained, mucous membranes have been built all for the egg to be ready to be fertilized. If the egg is not being fertilized, afterwards the body gets rid of it and this is the period. So there is a building up phase, if its not being fertilized then there is a releasing phase – just like the waning phase between a full moon and new moon, says Iris.

However, many women have conceived at a time when theoretically it should be impossible to conceive according to the female hormonal cycle. The reason, according to Czechoslovakian doctor, Eugen Jonas, has to do with the time and date we are born.

Dr Jonas arrived at his theory in the 1950s, at a time when countries like Russia, Czechoslovakia and Bulgaria first legalized abortion. Dr. Jonas felt that, even though the procedure was legal, women and medical practitioners weren’t equipped to deal with the physical, mental and emotional repercussions of abortion, so wanted to find a better way of helping women avoid unwanted pregnancies and abortion altogether.

Curious about an old Babylonia saying that, “Woman is only fertile during a certain phase of the moon,” Dr. Jonas used this as a starting point for his research. Based on his investigations and the observations of his friends and colleagues, he came to the conclusion that there is another cycle running parallel to our hormonal cycle. That cycle is our personal moon cycle.

Based on his findings, Dr. Jonas established a birth chart for every woman he worked with and was able to calculate the days that they were fertile outside the hormonal cycle.

He discovered that using the first day of the last period to calculate the delivery date is rarely correct. This calculation is based on the hormonal cycle of the woman and is still used by today’s medical profession.

Dr. Jonas calculated the conception date by using the position and phase of the moon at birth in the female chart and found that the fertile days are the three days just before the moon is at the same phase as it was at her birth. He used this method to calculate the conception day and based on that the possible delivery date of the baby.

He also found that the gender of the child is determined by the gender of the (tropical) sign the moon is in during conception. While male signs like Aries, Leo and Libra seem to produce more baby boys, female signs like Taurus, Cancer, Scorpio, turn out more baby girls.

It was not long after that a gynaecologist in Prague, Jiri Malek, showed some scientific interest in Dr. Jonas’ thesis. On Dr. Malek’s invitation, Dr. Jonas travelled to a maternity clinic in Bratislava where he was able to do more research and confirm his thesis.

Based on his findings, Dr. Jonas developed ‘The Lunar Method’ which has claims to be 97 per cent accurate in determining the female fertility cycle (for both conception and contraception) and the gender of a child conceived during this time.

Although Dr. Jonas travelled widely talking about his work, which was widely accepted by the medical profession at the time, his theory was lost to the West as a result of Cold War and partitioning of Eastern Block countries. It was not until the Berlin Wall came down in 1989 that this information was released to the West again.

Every woman needs to know about Dr. Eugen Jonas’ Lunar Method and Fertility Calculator! Once you understand how it works you can plan or avoid pregnancies, says Iris.

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