The Supreme Court in the case of Republic vs. Cagandahan, GR No. 166676, September 12, 2008, upheld the decision of the Regional Trial Court in Siniloan, Laguna which allowed changes in the birth certificate of Jennifer Cagandahan as to (1) her first name from “Jennifer ” to “Jeff ” and (2) the entry for gender from female to male.
I have written previously a related post titled “Can a man who had a sex change operation have his birth certificate entry for gender changed from male to female?”. In that post, I discussed the 2007 Supreme Court decision in the “Rommel Jacinto Dantes Silverio vs. Republic of the Philippines” case. In the Silverio case, the Court did not allow the changes sought by Silverio in his birth certificate.
The difference between the Silverio and Cagandahan cases
Silverio had a sex change or reassignment operation in Bangkok, Thailand. On the other hand, Cagandahan has Congenital Adrenal Hyperplasia (CAH) which is a condition where a person possesses both male and female characteristics. As the Supreme Court stated:
[Cagandahan] simply let nature take its course and has not taken unnatural steps to arrest or interfere with what he was born with. And accordingly, he has already ordered his life to that of a male. Respondent could have undergone treatment and taken steps, like taking lifelong medication, to force his body into the categorical mold of a female but he did not. He chose not to do so. Nature has instead taken its due course in respondent's development to reveal more fully his male characteristics.Silverio deliberately took the sex reassignment operations to change his body to that of a woman. Cagandahan, on the other hand, from birth had a female body, male hormones, two sex organs, and no monthly period.
The facts of the Cagandahan case
 In her petition with the Regional Trial Court in Siniloan, Laguna, Jennifer alleged that she was born on January 13, 1981 and was registered as a female in the Certificate of Live Birth but while growing up, she developed secondary male characteristics and was diagnosed to have Congenital Adrenal Hyperplasia (CAH) which is a condition where persons thus afflicted possess both male and female characteristics.
 She further alleged that she was diagnosed to have clitoral hyperthropy in her early years and at age six, underwent an ultrasound where it was discovered that she has small ovaries. At age thirteen, tests revealed that her ovarian structures had minimized, she has stopped growing and she has no breast or menstrual development.
 She then alleged that for all interests and appearances as well as in mind and emotion, she has become a male person. Thus, she asked the Regional Trial Court in Siniloan, Laguna that her birth certificate be corrected such that her gender be changed from female to male and her first name be changed from Jennifer to Jeff.
 The petition was published in a newspaper of general circulation for three (3) consecutive weeks and was posted in conspicuous places by the sheriff of the court. The Solicitor General entered his appearance and authorized the Assistant Provincial Prosecutor to appear in his behalf.
Jennifer's condition: female body, male hormones, two sex organs, and no monthly period
 To prove her claim, Jennifer testified and presented the testimony of Dr. Michael Sionzon of the Department of Psychiatry, University of the Philippines-Philippine General Hospital. Dr. Sionzon issued a medical certificate stating that respondent’s condition is known as CAH. He explained that genetically respondent is female but because her body secretes male hormones, her female organs did not develop normally and she has two sex organs - female and male. He testified that this condition is very rare, that Jennifer’s uterus is not fully developed because of lack of female hormones, and that she has no monthly period. He further testified that Jennifer’s condition is permanent and recommended the change of gender because she has made up her mind, adjusted to her chosen role as male, and the gender change would be advantageous to her.
 The Regional Trial Court in Siniloan, Laguna granted the petition. The Office of the Solicitor General however brought the case up to the Supreme Court.
The Supreme Court’s ruling
 Respondent (Jennifer) undisputedly has CAH. This condition causes the early or “inappropriate” appearance of male characteristics. A person, like respondent, with this condition produces too much androgen, a male hormone. A newborn who has XX chromosomes coupled with CAH usually has a (1) swollen clitoris with the urethral opening at the base, an ambiguous genitalia often appearing more male than female; (2) normal internal structures of the female reproductive tract such as the ovaries, uterus and fallopian tubes; as the child grows older, some features start to appear male, such as deepening of the voice, facial hair, and failure to menstruate at puberty. About 1 in 10,000 to 18,000 children are born with CAH.
What is Congenital Adrenal Hyperplasia (CAH)?
 CAH is one of many conditions that involve intersex anatomy. During the twentieth century, medicine adopted the term “intersexuality” to apply to human beings who cannot be classified as either male or female. The term is now of widespread use. According to Wikipedia, intersexuality “is the state of a living thing of a gonochoristic species whose sex chromosomes, genitalia, and/or secondary sex characteristics are determined to be neither exclusively male nor female. An organism with intersex may have biological characteristics of both male and female sexes.”
How societies treat intersexuality
 Intersex individuals are treated in different ways by different cultures. In most societies, intersex individuals have been expected to conform to either a male or female gender role. Since the rise of modern medical science in Western societies, some intersex people with ambiguous external genitalia have had their genitalia surgically modified to resemble either male or female genitals. More commonly, an intersex individual is considered as suffering from a “disorder” which is almost always recommended to be treated, whether by surgery and/or by taking lifetime medication in order to mold the individual as neatly as possible into the category of either male or female.
 In deciding this case, we consider the compassionate calls for recognition of the various degrees of intersex as variations which should not be subject to outright denial. “It has been suggested that there is some middle ground between the sexes, a ‘no-man’s land’ for those individuals who are neither truly ‘male’ nor truly ‘female’.” The current state of Philippine statutes apparently compels that a person be classified either as a male or as a female, but this Court is not controlled by mere appearances when nature itself fundamentally negates such rigid classification.
 In the instant case, if we determine respondent to be a female, then there is no basis for a change in the birth certificate entry for gender. But if we determine, based on medical testimony and scientific development showing the respondent to be other than female, then a change in the subject's birth certificate entry is in order.
Biologically, nature endowed respondent with a mixed (neither consistently and categorically female nor consistently and categorically male) composition. Respondent has female (XX) chromosomes. However, respondent’s body system naturally produces high levels of male hormones (androgen). As a result, respondent has ambiguous genitalia and the phenotypic features of a male.
Determining factor in gender classification for intersex individuals
 Ultimately, we are of the view that where the person is biologically or naturally intersex the determining factor in his gender classification would be what the individual, like respondent, having reached the age of majority, with good reason thinks of his/her sex. Respondent here thinks of himself as a male and considering that his body produces high levels of male hormones (androgen) there is preponderant biological support for considering him as being male. Sexual development in cases of intersex persons makes the gender classification at birth inconclusive. It is at maturity that the gender of such persons, like respondent, is fixed.
Respondent here has simply let nature take its course and has not taken unnatural steps to arrest or interfere with what he was born with. And accordingly, he has already ordered his life to that of a male. Respondent could have undergone treatment and taken steps, like taking lifelong medication, to force his body into the categorical mold of a female but he did not. He chose not to do so. Nature has instead taken its due course in respondent’s development to reveal more fully his male characteristics.
 In the absence of a law on the matter, the Court will not dictate on respondent concerning a matter so innately private as one’s sexuality and lifestyle preferences, much less on whether or not to undergo medical treatment to reverse the male tendency due to CAH. The Court will not consider respondent as having erred in not choosing to undergo treatment in order to become or remain as a female. Neither will the Court force respondent to undergo treatment and to take medication in order to fit the mold of a female, as society commonly currently knows this gender of the human species. Respondent is the one who has to live with his intersex anatomy. To him belongs the human right to the pursuit of happiness and of health. Thus, to him should belong the primordial choice of what courses of action to take along the path of his sexual development and maturation. In the absence of evidence that respondent is an “incompetent” and in the absence of evidence to show that classifying respondent as a male will harm other members of society who are equally entitled to protection under the law, the Court affirms as valid and justified the respondent's position and his personal judgment of being a male.
 In so ruling we do no more than give respect to (1) the diversity of nature; and (2) how an individual deals with what nature has handed out. In other words, we respect respondent’s congenital condition and his mature decision to be a male. Life is already difficult for the ordinary person. We cannot but respect how respondent deals with his unordinary state and thus help make his life easier, considering the unique circumstances in this case.
 As for respondent’s change of name under Rule 103, this Court has held that a change of name is not a matter of right but of judicial discretion, to be exercised in the light of the reasons adduced and the consequences that will follow. The trial court’s grant of respondent’s change of name from Jennifer to Jeff implies a change of a feminine name to a masculine name. Considering the consequence that respondent's change of name merely recognizes his preferred gender, we find merit in respondent's change of name. Such a change will conform with the change of the entry in his birth certificate from female to male.
(Note: The narration of facts and the ruling are from the Supreme Court decision, but were broken up into numbered paragraphs for easier comprehension by laymen.)