ICSI is intra cytoplasmic sperm injection. It is one of techniques of Assisted Reproductive Technology (ART) that help couples to overcome ir infertility. In 1(51, sperm is directly injected into ovum, in vitro to form zygote, which is later implanted through ZIFT into woman.

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$?$ Human population whole number of peple or inhabitant in a country or region.

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$?$ Natality rate is average number of new individuals produced by a population reproductively active in a unit time. It is also known as birth rate.

$?$ Mortality rate is number of individuals dying in a unit time ,it is thus also known as death rate.

$?$ Immigration is when individuals from one population migrate to anor,this introduces new alleles in gene pool of a population. Population size increases.

$?$ Emigration is when individuals from one population go out to anor place, this leads to loss of certain genes in gene pool. Population size decreases

$?$ Age distribution is divided into three categories pre-reproductive,reproductive and post reproductive.

Abortion is technique in which foetus is removed from uterus before completion period of gestation. The medical termination of pregnancy (MTP) is considered as safe before 20 weeks of pregnancy. The first trimester is time considered as safe for abortions. The second trimester starts from 13th to 28th week of pregnancy. This is period where child develop organs and structures which are vital for life. The foetus is implanted deep in uterus and structure of placenta has been formed. The abortion is more dangerous in second trimester compared to first trimester because re are chances if heavy bleeding and or complications after termination of pregnancy.