Reproduction in Humans

Changes in Adolescence

The transition phase between childhood (phase of internal growth) and sexual maturity is known as adolescence. During this phase, the body proportions change, and new features and new sensations appear.

Some changes are common in boys and girls:

• Thick hairs in new parts of the body: Armpits and the genital area between thighs(area becomes darker);
• Thinner hairs appear on the legs, arms & face.
• Skin frequently becomes oily & pimples develop sometimes.
• Began to be conscious & aware of my own body & those of others in new ways.

Some changes are different between boys and girls

In Girls, the Breast size increases, darkening the skin of the nipple at the tips and they begin to Mensurate

In Boys, New thick hair grows on the face, voice begins to crack and Penis occasionally begins to become enlarged & erect.

Sexual Maturation

In some people, they happen early & quickly, while in others, they happen very slowly. Each change does not become complete quickly either. All these are aspects of Sexual Maturation.

Sexual reproduction needs specialised cell types in multi-cellular bodies to carry out specialised functions. When a body is growing to its adult size, the resources are directed towards achieving growth and maturation of reproductive tissue is not a major priority.

As the rate of general body growth begins to slow down, reproductive tissue begins to mature. This period of adolescence is known as Puberty.

Reproductive process:

Either external release of germ cells from the bodies of individuals. For example, Pollination in Flowering Plants. The Internal transfer of germ cells for fusion. For example, Mating in Animals. Some changes of puberty are mere signs of sexual maturity(For example, hair growth); Some are needed for reproduction; Some are needed after birth (For example, mammary Glands).

Male Reproductive organ:

It is composed of the Testis, Vas Deferens, Urethra and Prostate.

Testis

Germ cells- Sperm formation takes place. It exists outside the abdominal cavity in the scrotum since the formation of sperm requires a lower temperature than the normal body temperature. It has a role in producing a hormone called testosterone:

1. It regulates the formation of sperm.
2. Brings changes in appearance seen in boys at the time of puberty.

Vas deferens:

• Sperms are delivered through this tube which unites with a tube coming from the urinary bladder.

Urethra

• The urethra forms a common passage for sperm and urine.
• Prostate seminal vesicles glands add their secretions:

1. So sperms are now in a fluid which makes their transport easier.
2. Provides nutrition

Sperms

Sperms are tiny bodies that consist of mainly genetic material and a long tail that helps them to move towards female germ cells.

A Misconception: Sperm cells have mitochondria which supply energy to the cell till fertilisation takes place.

Female Reproductive organ:

Ovaries:

• It is a pair of glands, in the female reproductive system where egg/germ cells are made. They are responsible for the production of some hormones.
• Fallopian tube (or oviduct): It is a thin tube that has the function of carrying a female egg from the ovary to the womb.

Uterus:

Elastic bag-like structure; 2 oviducts unite here.

• The uterus opens into the vagina through the cervix, from where the sperm can enter for fertilisation.
• The uterus prepares itself every month to receive and nurture the growing embryo: The lining thickens and is richly supplied with blood to nourish the growing embryo.

Oocytes and Ovum

• When a girl is born, ovaries contain thousands of immature eggs called Oocytes. When puberty hits some of these start maturing at the rate of 1 per month by the ovaries.
• The matured egg is then called an Ovum.

Ovulation and Fertilisation:

• Every month body prepares itself to receive a fertilised egg. The lining of the uterus becomes thick and spongy to nourish the embryo if fertilisation takes place.
• An egg lives for about a day and a sperm cell lives for 5-7 days.
• Release of a mature egg from an ovary. Takes place in mid-cycle (14th day or so)
• When egg cells come down the fallopian tube, waiting sperm cells pound over it to fertilise.
• Sperms enter through the vaginal passage during sexual intercourse. They reach the oviduct (upward) and encounter the egg.

Menstruation

If no fertilization takes place, this lining slowly breaks and comes out through the vagina as blood and mucous. This is known as the Menstruation, which can last for 2-8 days.

Development of Embryo:

• The zygote (fertilised egg) gets implanted in the lining of the uterus and starts dividing. This is called an Embryo.
• Placentia: Special tissue, disk embedded in Uterine wall; helps embryo get nutrition from mother’s blood. It contains villi on the embryo side of the tissue.
• Contains blood spaces on the mother’s side, which is surrounded by villi.
• It supplies oxygen & glucose from the mother to the embryo.
• Waste substances generated are removed through blood.
• Development of a child takes approximately 9 months. It is born as a result of the rhythmic contraction of muscles in Uterus.

Contraceptive methods:

Gradual sexual maturation takes place while the body is still growing. Some degree of sexual maturation does not mean that the body or mind is ready for sexual acts and bringing up children.

Pregnancy makes major demands on the body. Often situation arises when she is not ready for it: ways devised to avoid pregnancy:

1. Creation of Mechanical barrier for sperm: Condoms, coverings for vagina
2. By changing the hormonal balance of the body: Eggs are not released & fertilisation can’t occur. Oral pills. : Have side effects.
3. Other contraceptive devices: loop or copper T placed in the uterus. [Side effects: irritation in uterus]
4. Surgical Methods: If the Vas deferens in the male is blocked: sperm transfer can be prevented & if the Fallopian tube is blocked egg can’t be transferred. Safe in the long run. [Side effects: Can cause infections & other problems if not properly performed]
5. Surgeries to remove unwanted pregnancies. [Limitation: used for female foeticides or sex-selective abortion]

Sexually transmitted diseases

It refers to those diseases that are transferred during sexual acts.

• Bacterial infections: Gonorrhoea & Syphilis.
• Viral Infections: Warts & HIV-AIDS.

Infertility

Infertility refers to the inability to conceive after one year of regular, unprotected intercourse. Both men and women can experience infertility, and various conditions contribute to it.

• Female Infertility:
  1. “Poor Ovarian Response” (POR), where a woman produces a significantly low number of eggs (oocytes) when stimulated with fertility drugs during an IVF cycle, indicating a diminished ovarian reserve and potentially impacting pregnancy chances.
  2. Polycystic Ovary Syndrome (PCOS or PCOD): Hormonal imbalance that affects ovulation. It can improve through hormonal therapy and other medical options.
  3. Endometriosis: Tissue growing outside the uterus can cause scarring and blockages.
  4. Blocked Fallopian Tubes: Often caused by infections or pelvic inflammatory disease.
  5. Age: Female fertility declines with age, particularly after 35.
• Male Infertility:
  1. Low Sperm Count: A reduced number of sperm can lower the chances of fertilization.
  2. Poor Sperm Motility: Sperm may not move efficiently to reach the egg.
  3. Erectile Dysfunction: Difficulty achieving or maintaining an erection can affect fertility.
  4. Varicocele: Swelling of veins in the scrotum, which can reduce sperm quality.

Treatment options for infertility include medication, surgery, lifestyle changes, and assisted reproductive technologies like IVF.

Assisted Reproductive Technologies

1. Gamete (sperm or oocyte) donation.
2. IVF: in–vitro–fertilisation – It includes fertilising an egg in the lab.
   • Freshly released gametes from the parents are collected & kept together for a few hours to fertilize; The woman undergoes hormone therapy to stimulate the ovaries to produce multiple eggs, as opposed to the single egg produced in a natural cycle.
   • The subsequently developed embryo is then allowed to develop for a week (Embryo culture). And then placed in the mother’s Uterus. It is also known as Test tube baby.
3. Gestational surrogacy: In such a situation, the child is not biologically related to the surrogate mother.  Eggs from the mother are fertilised with the father’s/donor’s sperm and then the embryo is placed into the uterus of the surrogate, who carries the child to term and delivers it.

Gestational Surrogacy:

When another woman carries and gives birth to a baby for the couple who wants to have a child.

• Gestational surrogacy: Eggs from the mother are fertilised with the father’s/donor’s sperm and then the embryo is placed into the uterus of the surrogate, who carries the child to term and delivers it.
  • The biological mother is still the woman whose eggs are used.
  • Surrogate is called the birth mother or Surrogate mother.
• Couples opt for surrogacy when traditional means of conceiving a child have failed, this also includes IVT, or it is dangerous for the couple to get pregnant and give birth.
• The following medical conditions usually necessitate surrogacy:
  • Malformation of or infection in the womb.
  • Absence or removal of the womb by hysterectomy.
  • Recurring miscarriages.
  • Repeated failure of IVF.
  • Other conditions that make it impossible or risky for a woman: is severe heart disease.

Three Parent Baby:

A new technique for abnormal mitochondria; If the egg cell of the biological mother is unhealthy, however, the genetic material is healthy enough. This can happen when the mitochondria of the cell are, for example, damaged. In this case, the egg cell of a toner can be transfused with the genetic material of the biological mother and then fertilised with a sperm.

Commercial surrogacy:

Legalized in India in 2002 after which India emerged as a surrogacy hub for couples from different countries. However, there have been several reported incidents concerning unethical practices such as:

• Exploitation of surrogate mothers and related health hazards, privacy.
• Abandonment of children born out of surrogacy: Sex-selective surrogacy.
• Rackets of intermediaries importing human embryos and gametes.
• Citizenship of the Child: Need for Adoption

Surrogacy (Regulation) Act, 2021:

• Surrogacy is defined as a practice where a woman gives birth to a child for an intending couple with the intention to hand over the child after the birth to the intending couple.
• Regulation of surrogacy:
  • Commercial surrogacy: Procedures are undertaken for a monetary benefit or reward (cash or kind) exceeding the basic medical expenses & insurance coverage.
  • Altruistic surrogacy involves no monetary compensation to the surrogate mother other than medical expenses and insurance coverage during the pregnancy.
• Eligibility criteria for intending couple: Surrogacy is permitted when it is:
  • For intending couples who suffer from proven infertility;
  • Altruistic, Not for commercial purposes;
  • Not for producing children for sale, prostitution or other forms of exploitation.
  • They should have a ‘certificate of essentiality’ and a ‘certificate of eligibility’ issued by the appropriate authority.
  • A certificate of essentiality will be issued upon fulfilment of the following conditions:
    1. A certificate of proven infertility of one or both from a District Medical Board;
    2. An order of parentage and custody of surrogate child passed by a Magistrate’s court;

• Insurance coverage for 16 months covering postpartum delivery complications for the surrogate.

• A certificate of eligibility is issued upon fulfilment of the following conditions:
  1. The couple is an Indian citizen and married for at least five years;
  2. Between 23 to 50 years old (wife) and 26 to 55 years old (husband);

• They do not have any surviving child (biological, adopted or surrogate); who is not mentally or physically challenged or suffers from life-fatal illness; and

• Eligibility criteria for surrogate mother: To obtain a certificate of eligibility from the appropriate authority, the surrogate mother has to be:
  • A close relative of the intending couple;
  • A married woman having a child of her own;
  • 25 to 35 years old, A surrogate only once in her lifetime; and
  • Possess a certificate of medical and psychological fitness for surrogacy.  Further, the surrogate mother cannot provide her own gametes for surrogacy. However, married couples can use donor eggs or sperm if one of the partners has a medical condition.
• Parentage and abortion of surrogate child:
  • Parentage: It will be deemed to be the biological child of the intending couple, and will have similar inheritance and citizenship rights.
  • Abortion:
    • compliance with the Medical Termination of Pregnancy Act, 1971,

1. the approval of the appropriate authority and
2. the consent of the surrogate mother is required.

• Appropriate authority: The central and state governments shall appoint one or more appropriate authorities within 90 days of the Bill becoming an Act.  Functions:
  • Granting, suspending or cancelling registration of surrogacy clinics;
  • Enforcing standards for surrogacy clinics;
  • Investigating and taking action against breach of the provisions of the Bill;
  • Recommending modifications to the rules and regulations.
• Registration of surrogacy clinics: Surrogacy clinics cannot undertake surrogacy-related procedures unless they are registered by the appropriate authority. Clinics must apply for registration within 60 days from the date of appointment of the appropriate authority.
• National and State Surrogacy Boards(NSB & SSB): Functions of the NSB include:

• • Advising the central government on policy matters relating to surrogacy;
  • Laying down the code of conduct of surrogacy clinics; and
  • Supervising the functioning of SSBs.

• Offences and penalties:
  • The offences under the Bill include:
    • Undertaking or advertising commercial surrogacy;

1. Exploiting the surrogate mother;
2. Abandoning, exploiting or disowning a surrogate child; and

• Selling or importing human embryos or gametes for surrogacy.
• The penalty for such offences is imprisonment up to 10 years and a fine of up to 10 lakh rupees.  The Bill specifies a range of offences and penalties for other contraventions of the provisions of the Bill.

Criticism of the Surrogacy Law

• Irrational Exclusions: Unmarried couples, single parents, live-in partners and homosexuals cannot opt for surrogacy. No provisions for trans-genders: LGBT.
• Narrow medical conditions which could prevent a woman from giving birth. A couple may be fertile but still, the pregnancy is risky.
• The term ‘close relative’ is not defined.
• Regarding eligibility Certificates: No time limit for eligibility certificates. The appeal process in case the application is rejected is not specified.
• Power to the regulator to issue more regulations may lead to excessive delegation of legislative powers.
• Abortion: The Bill does not specify a time limit for such approval by an appropriate authority. Further, the intending couple has no say in the consent to abort.

Assisted Reproductive Technologies (ART) Bill

The Assisted Reproductive Technology (Regulation) Bill, 2020, which aims to regulate ART services, was passed in the Lok Sabha in 2021 and is pending in Rajya Sabha.

• It Defines Assisted Reproductive Technology (ART) as all techniques that seek to obtain a pregnancy by handling the sperm or the oocyte (immature egg cell) outside the human body and transferring the gamete or the embryo into the reproductive system of a woman.  For example:
  • Gamete (sperm or oocyte) donation,
  • IVT: in-vitro-fertilisation (fertilising an egg in the lab), and
  • gestational surrogacy (the child is not biologically related to the surrogate mother).
• Regulation of ART clinics and banks:
  • ART services will be provided through:
    1. ART clinics, which offer ART-related treatments and procedures, and
    2. ART banks, which store and supply gametes.
  • National Registry of Banks and Clinics to register every ART clinic and Bank which will act as a central database with details of all ART clinics and banks in the country. State governments will appoint registration authorities to facilitate this process.
  • Condition for Registration: Registration would be possible if certain standards such as specialised manpower, physical infrastructure and diagnostic facilities are met.
  • The registration will be valid for 5 years and can be renewed for a further 5 years.
  • It may be cancelled or suspended upon contravention of the provisions of the Bill.
• Conditions for gamete donation and supply:
  • Age of donor: A bank can obtain semen from males between 21 and 55 years of age, and oocytes from females between 23 and 35 years of age.
  • Reproductive/marital status: An oocyte donor should be an ever-married woman having at least one living child of her own(minimum three years of age).
  • The woman can donate oocytes only once in her life and not more than seven oocytes can be retrieved from her.
  • A bank cannot supply the gamete of a single donor to more than one commissioning couple (couple seeking services).
• Conditions for offering ART services:
  • Written Informed consent of both the party seeking ART services as well as the donor is necessary before the ART procedures are carried out.
  • Insurance coverage for the oocyte donor (for any loss, damage, or death of the donor) by the party seeking ART services is necessary.
  • No Sex-determination: A clinic is prohibited from offering to provide a child of pre-determined sex.
  • The Bill also requires checking for genetic diseases before embryo implantation.
• Rights of a child born through ART: A child born through ART will be deemed to be a biological child of the commissioning couple and will be entitled to the rights and privileges available to a natural child of the commissioning couple.  A donor will not have any parental rights over the child.
• The National and State Boards for Surrogacy constituted under the Surrogacy (Regulation) Bill, 2019 will act as the National and State Boards respectively for the regulation of ART services, with the following additional Powers and functions:
  • Advising the central government on ART-related policy matters,
  • Reviewing and monitoring the implementation of the Bill,
  • Formulating code of conduct and standards for ART clinics and banks, and
  • Overseeing various bodies to be constituted under the Bill.
  • The State Boards will coordinate enforcement of the policies and guidelines for ART as per the recommendations, policies, and regulations of the National Board.
• Offences:

• • Abandoning, or exploiting children born through ART,
  • Selling, purchasing, trading, or importing human embryos or gametes,
  • Using intermediates to obtain donors,
  • Exploiting commissioning couple, woman, or the gamete donor in any form, and
  • Transferring the human embryo into a male or an animal

• Penalties:
  • For Individuals: Fine between 5 & 10 lakh rupees for the first contravention. For subsequent contravention: imprisonment for a term between eight and 12 years, and a fine between 10 and 20 lakh rupees.

Any clinic or bank advertising or offering sex-selective ART will be punishable with imprisonment between 5 -10 years, or a fine between Rs 10 lakh and Rs 25 lakh, or both.

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