Baretta, A. Section of Natural Methods of Family Planning. Institute Abif, Córdoba, Argentina. E-mail: [email protected]

González, L.A. E-mail: [email protected]


Background: the female diet previous to pregnancy chooses the sex of their children. It is desired to evaluate the microscopic changes that the intake works in the cervical secretions, and if these are related to the favoured spermatozoid.
Method: 40 women were evaluated with a historic diet favourable to spermatozoid “Y”, whose descendants were 76 sons and 1 daughter; the coefficient of minerals was quantified with the nutritional contents, by means a calculus chart. Later on they were followed, for three months, a favourable diet to spermatozoid “X”. It was evaluated an initial pre-diet cycle and a final post-diet cycle according to their registers of mucus (defining three qualities: elasticity – width – transparency) and sensation, photographs of the mucus, temperatures and test of LH.

Results: The first registered cycle shows abundant liquefaction of the secretions, , with thin/sharp/waterish mucus, transparent, in almost all the evolutionary days towards the peak, including in some cases an extra liquefaction at the start of the evolution of the mucus. In the last cycle studied, it is predominant the sensation of dryness, with dense/thick/dry mucus, semitransparent or white. The ovulation is often postponed with respect to the peak, previous some days of mucus in involution of fertile and absence of humidity.
Conclusion: The fertile pattern of women, who favour the conception of boys, is different from that of the women who favour the conception of girls. The cervical secretions modified by the diet, appear as the most favourable factor of spermatic selection
Key words: cervical mucus; fertility; choice of the baby’s sex; natural methods.


The intake of minerals in the female’s diet has influence in the sex of their descendants. A copy of Michele Duc’s PHD thesis (Labro, 1984) was made evaluating the relation: Sodium + Potassium / Calcium + Magnesium, (measurement that is made with the nutritional contents of such minerals in the food), and her conclusions were proved: in fact in percentages above 80%, women whose resultant coefficient is lower than 2, (belonging to rank one), favour the conception of females; and women whose coefficient is between 4 and 6, (belonging to rank three), favour the conception of males. (Baretta, 2006); in another way, it was determined that there are different microscopic types of cervical mucus, that make the heterogeneous structures. (Odeblad, 1994) (Menárguez, Pastor, Odeblad 2003); and that the diet works changing the pH towards a higher acidity in the mothers of girls and towards less acidity in the mothers of boys. (Baretta, 2006).

With regards to the incident of the ovulation, it can be observed historic and current criteria of association of simultaneity between ovulation and peak of mucus. Billings says: “At the highest point of fertility the mucus gives a definite lubricated sensation. The last day of this sensation is marked as the PEAK. This point is very close to the time of ovulation” The following day to the peak, it appears an abrupt involution to dryness, or to the personal Infertile Basic Pattern (IBP) of constant humidity. The pattern of the standard fertile mucus is always wet. “The end of the dry sensation means that the mucus has begun” (Billings E. and B.J. 2005-1) (Billings E and B.J. 2005-2)

The wet IBP of vaginal discharge, (Billings E. 2008) is described by Billings as “an unchanging pattern, which does not change in sensation or appearance, day after day and cycle alter cycle, in those early days alter menstruation” and that can be repeated in the lacteal phase. And that such humid IBP is exuded from vaginal cells, not mucus. However it is clarified that in a luteal phase and post peak, the first three days, it is not vaginal ooze, but dried up cervical mucus due to the activity of Shaw’s Bags, in answer to the rise of the progesterone.
On the other hand, the Syntothermic Method recognises that the ovulation cannot be determined with exactitude having as the only parameter the cervical mucus, and that the ovulation can happen two days before or after the peak. The Standard pattern has similar characteristics to the BOM (Billings’ Ovulation Method). (Otte, A and others, 2006)

With regards to the selection of sex, historically, Landrum Shettles concluded that the female secretions tend to be more alkaline when the ovulation is very near; and that at moments more distant from the ovulation, before or even after it, the secretions become more acid. (Shettles, 1987). He and other researchers coincide that the spermatic selection in the female genital tract depended then on the temporal distance to the ovulation, with fundament in the largest size, slowness and longevity of the spermatozoid “X”, so the coitus favourable to girls should happen at least 48 hours before the ovulation, and the coitus expecting to have boys should coincide with the ovulation, because the spermatozoid “Y” is faster and has less longevity (Shettles, 1961) (Billings y Westmore, 1983). However, Shettles himself recognises (Shettles, 1987) that other researchers (Guerrero, Harlap) report cases of boys conceived even up to five days before the ovulation and girls conceived after the ovulation. On the other hand, Wilcox (Wilcox and others, 1995) reached the conclusion that the moment of the sexual intercourse in relation to the ovulation has no influence on the baby’s sex.

The objective of this work was to study the pattern of cervical secretions, their macroscopic aspect in women mothers that historically conceived in their fertile life only males (with the exception of one, who conceived two boys and one girl), relating it with the intake or historic diet of a woman corresponding to a coefficient of minerals (between 4,0 and 6,0), which has an alkalinizing effect in the secretions and favours the spermatozoid “Y”; and the changes that operate in such pattern of the cervical secretions by means of a change to the corresponding diet to the coefficient of minerals (lower than 2,0), which acts making more acid those secretions and favours the spermatozoid “X”. All this is made, with the purpose of evaluating whether these patterns are comparable with a Standard model. Or on the contrary, that the pattern is substantially modified according to the woman’s intake.


Our methodology of work privileged the use of natural methods and personal and domestic indicators for the registry of the cycles with double verification: the determination of the happening of the ovulation (double parameter: test of LH and temperature), and the description of the mucus (double parameter: description of the woman by means of qualities requested and received photographs.
Syntothermic Method (STM): women have been adequately taught to register their cycles by means of the syntothermic method (SEGO, 2006), also asking them to describe the appearance of the mucus according to three (3) intrinsic characteristics established for the purpose of this study: 1- elasticity or not, 2- thickness (dense/fat/thick or fluid/thin/sharp) and 3- transparency or semi- transparency. It was also requested to register the intimate sensation that the secretions cause according to four characteristics: Dry – Humid – Wet- Lubricated (their initials). If it was noticed a progressive increase in the wetness, they could indicate it with the letters (VW or the expression “very wet”); and if they noticed a decrease of the humidity (in intensity, or in duration during the same day), they could indicate it with the small letter (“h”, or the expression “little humid”).

Photos of the cervical mucus: it was created an archive with photos of variables of the mucus. It was also requested that they took photographs of their mucus and they should forward them at the end of each cycle.
Peak of the mucus: within a frame of progressive evolution of fertile mucus and a sensation of humidity in increase, it was considered the peak the last day of maximum humidity with an abrupt involution to dryness (or to IBP) the following day.
Temperatures: according to instructions from STM. It was considered the most probable happening of the ovulation between the last low temperature and the first high one, according to the protocols of the Natural anti-conception of the Spanish Society of Gynaecology and Obstetrics.
Test of Luteinizin Hormone: it was requested to additionally do the test of domestic LH; it was considered the maximum of hormone LH as the only positive test, or the intermediate of two or more positives at the same distance (in the absence of positive it was taken the intermediate between weak positives); it was considered the most probable happening of the ovulation, 24 hours after such maximum of LH.
Evaluation of cycles: it was evaluated the complete cycle, between three or four cycles for each woman. The first cycle was considered the most concordant with its historic cycle with the diet of rank three. The last cycle (third or fourth, according to its length), was a distance in an average of three months from the first, and it was considered concordant with a diet in rank one.

Evaluation of the historic coefficient of minerals: it was made by means of a chart, size Excel, programmed to calculate the coefficient Sodium + Potassium / Calcium + Magnesium according to the nutritional information of each food (Peña G. 1997), and reception of the composition informed on the labels of industrial food together with a detail of the consumed quantities and frequencies of all solid and liquid food, given by the women about their historic feeding.
Access to rank one: it was made by means of a nutritionally balanced diet, with high levels of calcium/magnesium and low of sodium/potassium, calculated with the same chart.
Internet and E-mail: Internet and E-mail were necessary to send and received data because the women participants alive in different countries of Spain and Latin America. Access requested by them to change their eating habits to conceive girl.


The population was formed by 40 women, between 25 and 37 years old belonging to rank three, mothers of 77 children: 76 males and one female. Coefficient of minerals: Sodium + Potassium / Calcium + Magnesium, at the beginning, between 4, 40 and 5, 89.
It is required an initial healthy condition and without interruption with absence of medicaments and pharmaceutical multi-mineral complements or nutritional complements, and no use of contraceptives during the study.


In the 40 women it was observed concordance between two indicators of ovulation (maximum of LH 24/48 hours before the first high temperature), so it as considered that in all cases the happening of the ovulation because of double corroboration, intermediate between the maximum of LH and the first high temperature, As regards the relationship between ovulation and peak, it was discovered in several cases the absence of synchronization between both of them, circumstance that evaluated together with other differences in the secretions attributable to the previous diet, makes it important to consider that these two indicators do not always coincide.
The diversity of the individual fertile pattern of each woman prevents the transversal quantitative comparison to establish statistical data that reflect results of importance. But a “longitudinal” value in time in each one of the women (individual and chronologically), permitted the observation of very noticeable ordinary characteristics.

A- Characteristics of the first studied cycle: a humid IBP was frequently observed. Abundant liquefaction of the mucus in progressive increase: several days humid, wet, or wet/lubricated, in harmony with abundant thin/sharp/waterish mucus, quite transparent and elastic. In some cases the mucus of the peak is destroyed and falls like water, without consistency. Little dense/thick/dry/ blurred mucus separated several days before the peak. It is often observed an extra liquefaction, at the beginning of the evolution of the mucus, which was named “mini peak”, and it appears as characteristic in many women of rank three. The peak is evident according to Standard patters, with abundant liquefaction and immediate involution of lumpy mucus. The ovulation can simultaneously happen with the peak, but in many cases it occurs one or two days before (this event was denominated negative lack of coincidence), in which case it is surrounded, before and sometimes later, by a great liquefaction of the mucus. The mucus and predominant fertile sensations in the last cycle can be noticed during the peak and before that for several days, and also in the mini peak.
In the Table I and Photograph I it is presented a witness case (woman “A”) with a mini peak of mucus and a negative lack of coincidence (chart and photographs).

B- Characteristics of the last studied cycle: dry IBP, noticeable dehydration of the mucus with a constant sensation of dryness in harmony with abundant dense/thick/dry, semi-transparent/white mucus, with a decrease in the elasticity. Sometimes because of its great consistency it is impossible to visualize it without the cervical checking with palms and fingers of their hands. In harmony with the days of the peak, it can be observed for few hours some thin/sharp/waterish/, elastic mucus, little transparent, or it is directly substituted by a dense/thick creamy, semi transparent/whitish, elastic, even though not extremely dry mucus. The peak of the mucus can have 24 or 48 hours of light humidity and/or some detailed sensation of wetness, that is why it is of difficult identification according to the standard indicators. The mini peak becomes considerably reduced the same as the peak. The ovulation is produced, one, two, three days and sometimes four days after the reduced peak of the mucus, surrounded by dense mucus and a sensation of dryness (the event was denominated positive lack of coincidence) and this is more evident when the diet corresponds to a very low coefficient of minerals between 1,30 and 1,40. In the cases of positive lack of coincidence, the involution is not abrupt to Clotted mucus, but it is observed during these days involutionary mucus of fertile characteristics, similar to that of the evolution: dense/thick/dry, semi transparent/white, with a decrease of elasticity and absence of humidity, until the happening of the ovulation. In the Table II; Photograph II and Photograph III a witness case is presented (woman “B”) with four days of positive lack of coincidence (charts and photographs).


1- Women who until then had conceived boys, with a diet of rank three, possess a cervical pattern characterized by abundant liquefaction, including and extra liquefaction at the beginning of the evolution of the mucus. The ovulation happens with frequency before the peak and always accompanied by such secretions. It is then deduced that any sexual intercourse placed in this pattern of mucus, it is very probable that will result in the conception of males, according to the relation coefficient of minerals/sex of the descendants. (Labro, 1984) (Baretta, 2006) independently of the distance from the ovulation.

2- The rank one diet makes the secretions acid and radically transforms the pre-existent cervical pattern predominating the dehydration, thickness and little elasticity of the mucus, with a sensation of dryness during almost all the fertile days. When the coefficient is quite low (1, 30 – 1, 40), the ovulation occurs delayed as regards the peak, in this case, between them it is observed mucus in involution of fertile characteristics, in an average of two days. This mucus post peak does not correspond to a luteal phase (Billing, 2008) but it is totally fertile and pre-ovulate. The ovulation happens always accompanied by the predominant secretions of this pattern rank one. We can interpret that these cervical secretions are the ones in favour of the conception of girls, according to the relation coefficient of minerals/sex of the descendants, and can coincide or not with the ovulation.

As it is clear from the observations of this study that the spermatic selection does not depend on the speed and/or longevity of the spermatozoids, but of the cervical secretions. And that the quality of such secretions depends on the diet previous to the conception, according to the coefficient of the minerals mentioned.
As a consequence there is a coincidence with the conclusions of Wilcox and colleagues that the sex of the baby has no relation with the happening of the ovulation. But it is noticed that in some women it can have more connection with the happening of the peak. During the peak of the mucus, it would favour a boy, and distant from the peak, it would favour a girl. It was evaluated as probable that Shettles had enunciated his rules considering the peak and ovulation were simultaneous events. And besides he has taken into account the variations from woman to woman due to their diet.


The pattern of the cervical mucus of women who conceive boys is very different from the one of women who conceives girls, and the quality of the secretions is related to the coefficient of the minerals in their diets. The cervical secretions appear as the most probable factor of spermatic selection, and not the longevity or of the spermatozoids, or the distance to the ovulation. It is necessary to study this theme more deeply, not only for the pre-determinant capacity of the sex that the cervical secretions have, but for the already known potential as selectors of the defective spermatozoids, because they can provide advances as a precaution against illnesses; also for their application in the methods o natural planning of the family. The patterns enunciated as “Standard” are not common to all the female population, and many women would not feel identified with them. Finally, it is necessary to adapt the vocabulary used to enunciate the rules in natural methods, distinguishing between, “peak of the mucus” and “ovulation” as two events that might coincide in time or not.




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