Human Sexuality: Biology, Reproduction, and Health

Understanding Human Sexuality

Human sexuality encompasses three fundamental aspects:

• Biological: The physiological and anatomical differences between sexes.
• Spiritual: The emotional and relational dimensions of sexuality.
• Socio-cultural: How society and culture shape sexual norms and behaviors.

Biological Foundations of Sex

The differentiation between the two sexes begins at the cellular level. In a zygote, if the 23rd pair of chromosomes has the characteristics XY, the individual is male; if XX, the individual is female. From that moment, primary sexual characteristics (reproductive organs) begin to form. At puberty, secondary sexual characteristics develop due to hormone production, leading to changes in body shape, voice tone, and hair growth.

Female Hormonal Cycle

The female hormonal cycle is crucial for reproduction and consists of two main phases:

• Ovarian Cycle

  Lasts approximately 20 days and has two phases: the follicular phase and the ovulation phase. This cycle involves the production of progesterone and prepares the uterus for potential implantation.

• Menstrual Cycle

  Typically lasts about 8 days. It involves the shedding of the uterine lining, resulting in bleeding due to the breaking of blood vessels.

Cycle Overview:

• Days 1 to 20: Ovarian phase.
• Days 21 to 28: Menstrual phase.
• Days 6 to 13: Most fertile days.

Fertilization and Pregnancy

Fertilization

After sexual intercourse, fertilization occurs when one sperm unites with one ovule in the fallopian tubes.

Pregnancy

Approximately one week after fertilization, implantation occurs. Pregnancy is legally considered to begin from this point. During pregnancy, the placenta forms, facilitating communication between fetal and maternal blood. The amniotic sac also develops, protecting the fetus.

Sexually Transmitted Infections (STIs)

Sexually transmitted infections (STIs), previously known as STDs, are infections passed from person to person through sexual contact. Common STIs include:

• Syphilis

  Affects the central nervous system, skeletal system, and circulatory systems.

• Gonorrhea

  Caused by bacteria.

• Genital Herpes

  Caused by a virus, it can affect pregnancy.

• Candidiasis

  Caused by a fungus.

• AIDS (Acquired Immunodeficiency Syndrome)

  A spectrum of diseases that occur when resistance to HIV (Human Immunodeficiency Virus) decreases.

Contraception Methods

Contraception refers to methods used to prevent pregnancy. They can be categorized as:

• Barrier Methods

  Prevent the passage of sperm.

• Hormonal Methods

  Increase estrogen levels or alter hormonal balance to prevent ovulation or implantation.

• Surgical Methods

  Permanent procedures.

• Natural Methods

  Methods often adopted based on religious or personal beliefs, such as the rhythm method.

Common Contraceptive Methods and Effectiveness (E):

• Diaphragm: (E) 98%
• IUDs (Intrauterine Devices): (E) 98%
• Female Condom: (E) 98%
• Male Condoms: (E) 98%
• Contraceptive Pills: (E) 99%
• Vaginal Rings: (E) 99%
• Hormone Patch: (E) 99%
• Intramuscular Implants: (E) 99%
• Vasectomy: (E) 99%
• Morning-After Pill (Emergency Contraception): (E) 99%
• Tubal Ligation: (E) 99%
• Billings Method (Cervical Mucus Method): (E) 60%
• Coitus Interruptus (Withdrawal Method): (E) 40%

Pregnancy Diagnosis

Pregnancy can be diagnosed through various methods:

• Clinical Diagnosis

  Symptoms include amenorrhea (absence of menstruation), morning sickness (vomiting and nausea), breast tenderness, and weight gain.

• Hormonal Diagnosis

  Detection of human chorionic gonadotropin (hCG) hormone in blood or urine.

• Imaging Diagnosis

  Around the 5th week, an embryo can be seen and its heartbeat heard via ultrasound.

Teenage Pregnancy: Can lead to loss of educational opportunities, decreased access to skilled employment, and increased poverty.

Abortion

Abortion refers to the termination of a pregnancy. It can be:

• Spontaneous Abortion (Miscarriage)

  Can be caused by underlying health conditions such as diabetes, hypertension, hypothyroidism, syphilis, or brucellosis. Also, accidental blows, injuries, or crashes can contribute.

• Induced Abortion

  Illegal in Argentina.

Implications of Unsafe Abortion:

• Increased genital and systemic infections.
• Infertility.
• Psychological disorders.
• Increased maternal mortality.