Getting to know the OC

Oral contraceptive pills are the most popular methods of birth control amon modern women. 

They came into use in the 1950s, when the action certain hormones had on the menstrual cycle was discovered. The oral contraceptives became widely used since 1961.

The contraceptives acts by inhibiting ovulation.[1]

Oral contraceptives can be divided into two types based on its content. The two types of female oral contraceptives pill which are widely available are:

•  Combined oral contraceptives pill contain estrogen and progestin

•  Progestin only pill(also known as 'small pills'

Emergency contraceptive pills (morning after pills) are taken at the time of intercourse or within few days afterwards.

  

Other types of oral contraceptive pill available are:

• ·         Mifepristone is an antiprogestogen which has been used as a daily oral contraceptive in investigational clinical trials.

• ·         Ormeloxifene also known as centchroman,is a selective estrogen receptor modulation which is taken once to two times per week. Ormeloxifene is approved as an oral contraceptive only in India.

The combination  birth control pill that contain estrogen and progestin can be further be classified to three types that are referred to as ‘monophasic’,’biphasic’ and ‘ triphasic’.

• Monophasic birth control pills deliver the same amount of estrogen and progestin every day.
• Biphasic birth control pills deliver the same amount of estrogen every day for the first 21 days of the cycle. During the first half of the cycle, the progestin/estrogen ratio is lower to allow the lining of the uterus (endometrium) to thicken as it normally does during the menstrual cycle. During the second half of the cycle, the progestin/estrogen ratio is higher to allow the normal shedding of the lining of the uterus to occur.
• Triphasic birth control pills have constant or changing estrogen concentrations and varying progestin concentrations throughout the cycle. There is no evidence that bi- or triphasic oral contraceptives are safer or superior to monophasic oral contraceptives, or vice versa, in their effectiveness for the prevention of pregnancy. [Melissa Conrad stoppler,2014]

The general use of oral contraceptives

 Oral contraceptives are used to prevent pregnancy or to regulate menstrual cycle. Certain brand of oral contraceptive pills can be used to treat acne or as a ‘morning after pill’ for emergency contraception which is taken immediately after intercourse.
Its use may also be for treatment of several disorders such as polycystic ovary and menstrual cramp..

Women take the pills by mouth to prevent pregnancy and when it is taken correctly,it is up to 99% effective. 

However the pill lacks in protecting against sexually transmitted disease,including HIV(the virus that causes AIDS). In this sense, the latex of male condom provides the most protection from sexually transmitted disease (STD).