Reproductive Health Class 12 Notes जनन स्वास्थ्य — कक्षा 12 जीव विज्ञान अध्याय 3

Revise these first (prerequisites)

• Human Reproduction chapter: menstrual cycle, fertilisation, implantation
• Basic role of the hormones FSH, LH, estrogen and progesterone
• How infection spreads (Class 8–9 level)

1. What is reproductive health?

   According to WHO, reproductive health means total well-being in all aspects of reproduction — physical, emotional, behavioural and social. So the mere absence of disease is not enough; correct information, safe practices and respect are also essential.

2. Why contraception?

   Contraceptives (गर्भनिरोधक) are used to prevent unwanted pregnancy and to maintain a gap (spacing) between children. An ideal contraceptive should be user-friendly, easily available, effective, reversible and free of side-effects — and it should not interfere with sexual drive.

3. Types of methods — at a glance

   Natural (periodic abstinence, withdrawal, lactational amenorrhea), Barrier (condom, diaphragm, cervical cap), IUDs (such as CuT), oral pills / injectables / implants, and surgical (vasectomy, tubectomy). Think of them as different locks on a door — each lock works in a different way.

4. MTP — explained

   Intentional termination of pregnancy before full term is called MTP. In India, it is legally permitted only under certain conditions and only by a qualified doctor (RMP). It is considered relatively safe in the first trimester (up to 12 weeks).

5. Prevention of STIs

   Infections that spread through sexual contact are called STIs — e.g. gonorrhoea, syphilis, genital herpes, HIV, hepatitis-B. Ways to prevent them: avoid unknown/multiple partners, use condoms, and get checked by a doctor immediately if in doubt. Most STIs can be treated if detected early.

6. Infertility and ART

   Some couples are unable to have children even without contraception — this is called infertility, and the cause may lie in either the male or the female. Such couples are helped by ART (Assisted Reproductive Technologies), such as IVF — in which fertilisation is carried out outside the body in a lab ("test tube baby").

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As per NCERT 2026-27 — every point you need for the board exam.

1. Reproductive health – WHO

   According to WHO: total well-being in all aspects of reproduction — physical, emotional, behavioural, social. In 1951, India was among the first countries to start 'family planning'; now there are RCH (Reproductive and Child Health Care) programmes.

2. Amniocentesis

   Taking amniotic fluid and checking the foetus's chromosomes — to detect genetic disorders. There is a legal ban on its use for sex determination (to prevent female foeticide).

3. Population explosion

   Population increased due to a decline in death rate, MMR and IMR. To control it: promoting small families, legal marriage age (girls 18, boys 21), contraceptives.

4. Ideal contraceptive

   User-friendly, easily available, effective, reversible, with few or no side effects, and no interference with sexual drive.

5. Natural methods

   Periodic abstinence (days 10–17 of the cycle), coitus interruptus, lactational amenorrhea (no ovulation for up to ~6 months during full breast-feeding).

6. Barrier methods

   Condoms (male: Nirodh, female), diaphragm, cervical cap, vault — they prevent the sperm and ovum from meeting. Condoms also protect against STIs.

7. IUDs

   Non-medicated (Lippes loop), copper releasing (CuT, Cu7, Multiload 375 — Cu ions reduce sperm motility), hormone releasing (Progestasert, LNG-20). Ideal for spacing.

8. Oral pills & injectables

   Progestogens or progestogen–estrogen combinations; they inhibit ovulation and implantation and thicken the cervical mucus. Saheli is non-steroidal and taken once a week (CDRI Lucknow). Emergency: pills/IUD within 72 hours.

9. Surgical (terminal) methods

   Vasectomy (male: cutting/tying the vas deferens), tubectomy (female: fallopian tube). Highly effective but very poor reversibility.

10. MTP

    Medical Termination of Pregnancy — legal in India since 1971; MTP (Amendment) Act 2017. Up to 12 weeks, the opinion of one registered doctor; 12–24 weeks, the opinion of two doctors. Comparatively safe in the 1st trimester.

11. STIs

    Gonorrhoea, syphilis, genital herpes, chlamydiasis, genital warts, trichomoniasis, hepatitis-B, HIV/AIDS. Hepatitis-B, genital herpes and HIV are not completely curable. Prevention: avoid unknown/multiple partners, use condoms, get tested early.

12. Infertility & ART

    IVF (test tube baby) → embryo transfer: ZIFT (zygote/embryo up to 8 blastomeres → fallopian tube), IUT (more than 8 blastomeres → uterus). GIFT (donor ovum → fallopian tube), ICSI (sperm injected directly into ovum), AI / IUI (semen into uterus in cases of low sperm count).

The concept in depth — the why and the how. Everything stays within the NCERT syllabus.

1. How do IUDs work?

   IUDs increase phagocytosis of sperms within the uterus. Cu ions released from copper-releasing IUDs (CuT, Cu7, Multiload 375) suppress sperm motility and fertilising capacity. Hormone-releasing IUDs (Progestasert, LNG-20) make the uterus unsuitable for implantation and the cervix hostile to sperms. They are ideal for those who want to delay pregnancy or space children.

2. Logic of pills from Chapter 2

   Oral pills contain progestogens or a progestogen–estrogen combination. They inhibit ovulation and implantation and alter the quality of cervical mucus so that sperm cannot move forward. Recall Chapter 2 — the LH surge induces ovulation; pills disturb this very hormonal signal. Saheli (CDRI, Lucknow) is a non-steroidal, once-a-week pill.

3. Misuse of amniocentesis

   In amniocentesis, cells from the amniotic fluid are used to check the foetus for genetic/chromosomal disorders. It began to be misused for sex determination, which increased female foeticide — so there is a statutory ban on its use for sex determination. In other words, the ethics of a medical tool depend on how it is used.

4. How to remember the differences between ART techniques?

   What is transferred and where — that is the key. ZIFT: zygote/early embryo (up to 8 blastomeres) → fallopian tube. IUT: embryo with more than 8 blastomeres → uterus. GIFT: donor's ovum → fallopian tube of a female who cannot produce an ovum but can provide a suitable environment. ICSI: sperm injected directly into the ovum. AI/IUI: in low sperm count, semen is introduced into the vagina/uterus.

5. Why are some STIs not completely curable?

   Hepatitis-B, genital herpes and HIV infections are not completely curable, whereas infections like gonorrhoea, syphilis and chlamydiasis can be treated if detected early. Hepatitis-B and HIV spread not only through sexual contact but also through infected needles, blood transfusion and from mother to foetus — which is why they are linked to Chapter 7 (Human Health and Disease). Because symptoms are mild in the early stage, people delay treatment, which can lead to complications (PID, infertility, ectopic pregnancy).

Common confusions — cleared up

1. ZIFT vs IUT

   Both involve embryo transfer: in ZIFT, an embryo with up to 8 blastomeres is transferred into the fallopian tube; in IUT, an embryo with more than 8 blastomeres is transferred into the uterus.

2. GIFT vs ZIFT

   In GIFT, the gamete (ovum) is transferred; in ZIFT, the zygote (already fertilised) is transferred.

3. Vasectomy vs Tubectomy

   Vasectomy in males (vas deferens cut/tied), tubectomy in females (fallopian tube cut/tied). Both have very poor reversibility.

4. Emergency contraceptive — within how long?

   Using pills/IUDs within 72 hours of unprotected coitus is effective as emergency contraception — it is not a regular method.

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