Biology (NTSE/Olympiad)  

7. Heredity & Evolution

Hormonal Methods of Contraception

Hormonal Methods of Contraception :
Oral Pills :
They contain progesterone with or without estrogen.
Implants :
They are subdermal devices which provide long term contraception, e.g., norplant.
Morning-After Pills :
They prevent contraception even after coitus, e.g., i pill,
Chemical Methods of Contraception :
They are creams, jellies and foaming tablets (vaginal pills) which are placed in vagina for killing the sperms at the time of coitus.
Reversible Sterilisation or Surgical Method :
It is of two types vasectomy in males and tubectomy in females.
Vasectomy :
The two vasa deferentia of the male are blocked by cutting a small piece and tying the rest. This prevents passage of sperms from testes to semen.
Tubectomy :
A portion of both the fallopian tubes is excised or ligated to block the passage of ovum.


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