Q.What is an oral contraceptive pill and how does it prevent pregnancy?

Hormonal contraceptive pills (taken by females) work by blocking ovulation, altering cervical mucus and the endometrium -- they cannot act on spermatogenesis, which occurs in a different individual's body altogether.

Oral contraceptive pills contain synthetic oestrogen and/or progestogen and are taken by women to prevent pregnancy. Their genuine mechanisms of action include: inhibiting ovulation by suppressing the mid-cycle LH surge needed to trigger release of the egg; altering the consistency of cervical mucus so that it becomes thick and hostile to sperm transport; and modifying the uterine endometrium so that, even if fertilisation somehow occurred, the lining is unsuitable for implantation of the blastocyst. Since these pills act entirely within the female reproductive tract and endocrine system, they have no physiological pathway to inhibit spermatogenesis, which is the production of spe …

Tubectomy is a terminal (permanent) method of birth control that surgically blocks the fallopian tubes.

Birth control methods are broadly natural, barrier, IUD/hormonal, and terminal (sterilisation) methods.

• Withdrawal method — a natural/behavioural method (coitus interruptus), not permanent.
• Implantation — not a contraceptive method at all; it refers to the attachment of the blastocyst to the uterine wall during pregnancy.
• Lactational amenorrhoea — a natural, temporary method relying on the absence of menstruation during intense breastfeeding. …

Copper-T is a copper-releasing intra-uterine device (IUD); the copper ions it releases suppress sperm motility and thereby reduce the sperm's ability to fertilise the ovum.

Copper-T (Cu-T) is one of the most widely used intra-uterine devices (IUDs) for contraception. It works mainly through a chemical (not purely mechanical) mode of action:

• The copper wire wound around the device continuously releases Cu²⁺ ions into the uterine cavity.
• These copper ions create a spermicidal (toxic) environment in the uterus that suppresses sperm motility and reduces the sperm's capacity to fertilise the egg. …

Oral contraceptive pills prevent pregnancy mainly by suppressing FSH and LH secretion, which blocks ovulation.

Oral contraceptive pills contain synthetic progestogens (often combined with estrogens). Through a negative-feedback effect on the hypothalamus and anterior pituitary, these hormones inhibit the secretion of GnRH and, in turn, FSH and LH, particularly preventing the mid-cycle LH surge that normally triggers ovulation -- so no egg is released and pregnancy cannot occur. Option (a), stimulating release of FSH and LH, is the opposite of what happens. Option (b), blocking the fallopian tube, describes tubal ligation/sterilisation, not the pill. Option (c) …