Authors: Baretta A y Rao A

Translator: González, L

Background: The female diet previous to pregnancy chooses the sex of their children, modifying the pattern of the cervical mucus. It is desired to evaluate the results of synchronizing coitus with the cervical secretions (CS) considered adequate for each spermatozoid according to the diet. Method: It was evaluated the coefficient of minerals (Sodium + Potassium /Calcium + Magnesium) of the historic diet of 4 women whose descendants were 12 males (three sons each one); a first cycle was interpreted, which was considered coherent with its historic diet, by means of personal registers according to Syntothermic Method (STM), photographs of the mucus and domestic test of LH; the coefficient of minerals was quantified with the nutritional contents in the food, by means of a calculus chart. Later on they went on, for three months, with a favourable diet to spermatozoid “X”, and the macroscopic changes in the quality of their CS were evaluated in the third cycle. Finally another population of 39 women in identical conditions were given some instructions to synchronize the coitus in the fourth cycle according to the CS observed day by day, choosing the women who got pregnant throughout a year. Those women who followed the indications of coitus to favour the sperm “X” (Test Group) were included as well as those who went against them. (Control Group). Results: On the population of the 39 women, in 94, 87% of them, the sex of their children responded to the quality of the simultaneous CS with their fertile coitus (FC), whatever the distance to the ovulation was. Conclusion: The cervical secretions, modified by the diet, are decisive of the spermatic selection.
Key words: cervical mucus, cervical secretions; choice of the baby’s sex, natural methods; sex ratio.


The intake of minerals in the females’ diet according to the relation: (Sodium + Potassium) / (Calcium + Magnesium), measurement that is made with the nutritional contents of such minerals in the food, has influence on the sex of the descendants. Different studies (Lorrain et Gagnon, 1975) (Duc, 1977) (Stolkowski et Duc, 1977) (Stolkowski et Lorrain, 1982) (Papa et all, 1983) (Labro, 1984) (Stolkowski et Choukroun 1986), concluded that in percentages of about 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. They attributed to the spermatic selection to the different electronic charge of each spermatozoid and to a bi-polarity of the ovum product of the diet; they manifested that 20% of the failures is still maintained in populations with very controlled diets.
Landrum Shettles and other researchers (Shettles,1987) (Shettles,1961) (Billings and Westmore,1983) coincided that the spermatic selection depended on the temporal distance to the ovulation, with fundament in the greatest slowness and longevity of the spermatozoid “X”, so the FC favourable to girls should happen at least 48 hours before the ovulation, and the FC favourable to boys should coincide with the ovulation, because the spermatozoid “Y” is faster and has less longevity. However, Shettles himself recognises (Shettles, 1987) that other researchers (Guerrero, Harlap) reached opposite conclusions and more recent investigations, Wilcox (Wilcox and others, 1995) reached the conclusion that the moment of FC in relation to the ovulation has no influence on the baby’s sex.
In another way, it was determined that there are different microscopic types of cervical mucus that make the heterogeneous structures along the fertile pattern of each woman (Odeblad 1992) (Odeblad 1994) (Menárquez et all 2003).
The objective of this work was to study the pattern of CS, their macroscopic aspect in women mothers that historically conceived in their fertile life only males relating it with the intake or historic diet of a woman corresponding to a coefficient of minerals (between 4,0 and 6,0), which favours the spermatozoid “Y”; to evaluate the changes that operate in such pattern of CS by means of a three months’ diet corresponding to the coefficient of minerals (lower than 2,0) that favours the spermatozoid “X”. Finally, to propose the synchronization of coitus to favour the spermatozoid “X” according to the CS observed day by day in the pattern modified by a diet, with the objective to establish the existing relationship between the quality of the CS, the content of minerals in the diet, the distance to the ovulation, and the baby’s sex.


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: 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 CS 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).

Peak of the mucus: it was considered the peak the last day of maximum humidity with subsequent involution the following day. Temperatures: 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. Photos of the cervical mucus: it was created an archive with photos of variables of the CS. It was also requested that they took photographs of their mucus and they should forward them at the end of each cycle.


Test of Luteinizing Hormone: it was requested to additionally do the test of domestic LH; it was considered the maximum of LH as the only positive test, or the intermediate of two or more positives at the same distance (in the absence of positives 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 three cycles for each woman in population “I”. The first cycle was considered the most concordant with the diet of rank three. The last cycle was at a distance in an average of three months from the first, and it was considered modified by the diet of rank one. In population “II” it was also evaluated the cycle of conception with reference to the intercourses they had had.


Evaluation of the 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 levels of sodium/potassium, calculated with the same chart to answer to a coefficient between 1,30 and 1,40.


Internet and E-mail: the women participants live in different cities of Spain and Latin America that is why the electronic mail was put into practise in the process of sending and receiving data. They contacted us with the purpose of favouring the conception of girls.
Indications to favour the spermatozoid “X”: it was indicated to place the coitus at a distance of at least 36 hours before or after any liquefied CS symptom of liquefaction in secretions characteristic of the peak of the mucus, and coinciding with mucus little elastic, dense/thick, off-white/dull, with a sensation of dryness, even if it was simultaneous with the ovulation.



I- The population “I” was formed by 4 women, between 25 and 37 years old belonging to rank three, mothers of 12 boys. Coefficient of minerals: at the beginning between 4, 40 and 5, 89. (SD = 0, 46), and at the end between 1, 30 and 1, 40.
It was 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.
II- The population “II” was formed by 39 women in identical conditions to the population “I” (SD = 0, 36) and who became pregnant after three months of diet and before a year of attempts.
In the population “II” were included those who followed the indications of coitus to favour the sperm “X” (Test Group) as well as those who went against them. (Control Group)



I. In the 4 women of the population “I” it was observed concordance between two indicators of ovulation (maximum of LH 24/48 hours before the first high temperature), so it was 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.
Characteristics of the first studied cycle (historic coefficient rank three)


● Abundant liquefaction / alkalinization of the mucus in progressive increase
● Little mucus slightly dense far away for several days before the peak.
● Extra liquefaction at the beginning of the evolution of the mucus.
● The peak is simultaneous or it is postponed as regards the ovulation, for which this happens in the middle of very alkaline secretions (this event was denominated negative lack of coincidence between the ovulation and the peak)
● In evolution as well as in the peak/ovulation, predominates the liquefied mucus very alkaline, and the involution is abrupt and sudden.


A witness case (woman “A”) is presented in the Table “I” and the Photograph “I”.
Characteristics of the last studied cycle (coefficient 1,30 -1,40 for three months of diet):


a) Considerable dehydration /acidity of the mucus.
b) Little thin/watery mucus in the peak.
c) The extra initial liquefaction diminishes or disappears.
d) The peak can only have 24 or 36 hours of alkaline secretions and goes back to one, two, three, and sometimes four days before the ovulation, which, for this reason, is seen surrounded by secretions more acid of involution. (this event was denominated positive lack of coincidence between the ovulation and the peak).
e) The involution is not abrupt, and in the evolution as well as in the involution the predominant mucus has characteristics of low alkalinity.
It is presented in the Tables “II”, “III”, “IV”, Photograph “II” and Photograph “III” a witness case (woman “B”) with four days of a positive lack of coincidence.
II. The 39 women in the population “II” responded the general expressed characteristics of the cycles, hey got pregnant in a period between three months and a year since the beginning of the diet. Twenty three of them conceived according to the indications given to favour sperm “X”, and sixteen voluntarily chose the rules of Shettles’ method, at a distance of at least 48 hours before the ovulation and coinciding this way with the residual alkaline CS post diet, even when they were warned that in this was they would favour the spermatozoid “Y”.



a. Seventeen (17) had only one FC after at least 48 hours after the peak (during thick mucus in evolution), at full ovulation with a positive lack of coincidence: they conceived sixteen girls and one boy.
b. Six (6) had only one FC at 48 hours before the peak (during thick mucus in evolution): they conceived six girls
c. Sixteen (16) women had one FC at a distance of at least 48 hours before the ovulation (during liquated mucus/ sharp pf the peak) and also after the peak: they conceived fifteen boys and one girl.



As a summary:
Test Group: Out of twenty-three women (a, b) who obeyed the indications, twenty-two conceived girls, depending the sex of their children, except one, on the quality of the CS at the moment of the FC, and independently of the distance to the ovulation.
Witness Group: Out of sixteen women (c) who disobeyed the indications, fifteen conceived boys, depending the sex of their children, on the quality of the CS at the moment of the FC, having been distant at least 48 hours before the ovulation.
From these results (1) and (2) it is inferred the sex of the off-springs responded to our hypothesis in 37 out of 39 births, meaning 94,87% of favourable results.
Appraising the results according to the rules of Shettles’ method, of the 39 evaluated cases, only six (b) had FC several days before the ovulation and conceived girls, which added to the two failures of our hypothesis (a, c) they sum up eight cases that would mean 20,52% of the successes.
Baretta Method


Shettles Method

1. The 4 women who had conceived only boys until then, with a diet of rank three, had a pattern of mucus characterised by abundant liquefaction. The ovulation happened before the peak, and it is always accompanied by the mentioned alkaline CS. At first we can deduce that any FC placed in this pattern of the mucus will probably cause the conception of males, according to the coefficient relation of minerals / sex of the descendants (Lorrain,1975) (Duc, 1977) (Stolkowski et Duc, 1977) (Stolkowski et Lorrain, 1982) (Papa et all, 1983) (Labro, 1984) (Stolkowski et Choukroun 1986) (Baretta, 2006), independently of the distance that separates them from the ovulation.


2. The diet of the women who get into rank one at least for three months, which is favourable to the descendant of girls, radically transformed the pre-existent cervical pattern, predominating dehydration of the mucus. When the coefficient of minerals is rather low (1,30 – 1,40), the ovulation happens delayed as regards the peak; in this case, between both of them, it is observed mucus in involution, again thick and dehydrated, but with fertile characteristics, in an average of two days. This mucus post peak does not correspond to a luteal phase (Billing, 2008) but it is pre-ovulate.
The ovulation happens simultaneously with the CS of involution.


3. It has been proved that these thick and dehydrated CS are the ones that favour the conception of girls, in total accordance with the relation coefficient of minerals/sex of the descendants, and may coincide or not with the ovulation.
Two or three days before the ovulation, even after three months of diet, a reduced peak of the mucus was maintained, which still had characteristics of liquefaction and these residual alkaline CS favoured the conception of boys.
As a consequence there is a coincidence with the conclusions of Wilcox, and with regards to 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 favoured a boy, and distant from the peak, it favoured a girl, and this study has been corroborated in 94,87% of cases.


The relation with regards to the temporal happening of the ovulation (Shettles’s Method) was verified in only 20, 51% of the cases studied.
Finally, it is considered the 20% of the persistent failures manifested by other researchers in previous studies about the diet, could be that the factors of spermatic selection is not the bi-polarity of the ovum, but the diversity of the CS and the mucus pattern corresponding to each diet; and in these last ones they are not modified in a complete way in a diet marked out by time.
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.



Baretta, Adriana: Conception and design of the research; acquisition, analysis and interpretation of data; drafting the article; review and approval the English translation. E-mail: [email protected]

Rao, Anabella: Design calculation tool (coefficient of minerals); statistical analysis of data; preparation of charts; critic review the content of the article; final approval article. E-mail: [email protected]

González, Luis: Public translator: Spanish-English. E-mail: [email protected]



The spermatic selection does not depend on the speed of the spermatozoids, and/or length of the spermatozoids, neither on the distance of the FC with the ovulation nor on the bi-polarity of the ovum, but on the CS of the male gametes they find in their distance travelled within the female genital apparatus. The quality of this CS as well as the cervical pattern which are within the cycle, depend on the previous diet to the conception, according to the coefficient of minerals (Sodium + Potassium) / (Calcium + Magnesium).




Baretta A. (2006) Niña o niño, ya puedes elegir. Colección Salud y Familia, Eduforma, Editorial Mad, Sevilla; pp 52-54.

Billings E and A. Westmore (1983) Il Método Billings. Trad. al italiano de A. Capella, Milán; pp 69-70.

Billings E. (2008) The Basic Infertile Pattern. Boletin Woombs 35, Nº 3.
Duc M. (1977) De l’influence des apports nutritionnels en ions K, Na, Ca, Mg, sur le sexe ratio chez l’homme. Thèse de doctorat en medicine, Paris.
Labro F & F. Papa (1984) Elige el sexo de tu hijo. Ediciones Martínez Roca, Barcelona; pp 75-76

Lorrain J et R. Gagnon (1975) Sélection préconceptionnelle du sexe. Union Médic.Canada; 104: pp 800-803.

Menárguez M et all. (2003) Morphological characterization of different human cervical mucus types using light and scanning electron microscopy. Human Reprod; 18-9: pp 1782-1789.

Odeblad E. (1994) The Discovery of Different Types of Cervical Mucus and the Billings Ovulation Method. Bulletin of the Natural Family Planning Council of Victoria; 21-3

Odeblad E. (1992) Recent research on cervical mucus. In Proceedings III Symposium Intemacional sobre Avances en Regulacion Natural de la Fertilidad 5-7 November 1992, Malaga. Eds. J. F. C. Navajas and E. G. Gracias.
Papa F et all. (1983)Sélection préconceptionnelle du sexe par la méthode ionique. J. Gynécol. Obstét. Biol. Reprod; 12: p 415.
Peña, G. (1997) Contenidos en Macronutrientes y Minerales. Tablas de Composición de Alimentos – Anexo 2.1, 17-36– Nutricia, Madrid.

SEGO. (2006) Anticoncepción Natural. Protocolo de la Sociedad Española de Ginecología y Obstetricia,

Shettles LB. (1961) Human spermatozoan shapes in relation to sex ratios. Fertil. Steril.; 12: pp 502-508

Shettles LB & D. Rorvik (1987) Como elegir el sexo de tu hijo, Ed. Plaza & Janes, Barcelona; pp 62-63; 84; 127-151

Stolkowski J & M. Duc (1977) Alimentation minérale (Na+, K+, Ca++, Mg++) chez les femmes n’ayant que des enfants du même sexe. Cahiers nutrition et diététique; 12-2: pp 153-156 et Union Médic. Canada 1977; 106: pp 1351-1355.

Stolkowski J & J. Lorrain (1982) Sélection préconceptionnelle du sexe. La vie médicale au Canada français; 11-3: pp 120 – 128.

Stolkowski J &t J. Choukroun (1986) Diététique et sélection préconceptionnelle du sexe. Revue française de diététique; 119-4: pp 4-9.

Wilcox A et all. (1995) Timing of sexual intercourse in relation to ovulation. Effects on the probability of conception, survival of the pregnancy, and sex of the baby. The New England Journal of Medicine; 333: pp 1517-21