The procedure of GIFT involves the transfer of female gamete to the Fallopian tube. Gametes cannot be transferred to the uterus to achieve the same result because the uterine environment is not congenial for the survival of the gamete.

If directly transferred to the uterus they will undergo degeneration or could be phagocytosed and hence, viable zygote would not be formed.

Intra Uterine Devices (IUDs) are inserted in the uterus through vagina and are presently available as the non-medicated IUDs,copper releasing IUDs and hormone releasing IUDs Cu ions-releasing IUDs are more efficient methods because

(i) Cu ions released suppress sperm motility and fertilising capacity of sperms.

(ii) It increases phagocytosis of sperms within the uterus.

(iii) It is one of the safest, most effective, convenient and least expensive reversible contraceptives available.

(iv) It has no systemic effects and can be safely used by breast-feeding women.

Following are some factors that have probably contributed to population explosion in India

(i) Ignorance and complete lack of awareness about the ill effects of increasing population especially in rural regions.

(ii) Poverty and illiteracy

(iii) Social stigmas about girl child and desire to have boy child.

(iv) Decline in death rate.

(v) Decline in maternal and infant mortality rate.

(vi) Increase in the young, reproductive age population.

IVF refers to in vitro fertilisation and ET refers to embryo transfer. Gametes from the male and female are collected hygienically and induced to fuse in the laboratory set up under simulated conditions.

The zygote formed is collected and is introduced into the uterus of a host or surrogate mother at an appropriate time (secretory phase). Early embryos (up to 8 cell) are generally transferred to the Fallopian tube whereas embryos with more than 8 cells are transferred to the uterus.

As no medicines or devices are used in these methods, side effects are almost nil.