contraception
1-Hormonal contraception They are among the most prescribed and
effective drugs.
Oral contraceptive pills:
Two types of preparations are used for oral contraception:
 Combinations of estrogens and progestins .They are further
divided into monophasic forms (constant dosage of both
components during the cycle) and biphasic or triphasic forms
(dosage of one or both components is changed once or twice
during the cycle).
 Continuous progestin therapy without concomitant administration
of estrogens.
 Postcoital pills which contains either estrogen alone or progestrin
alone or progestrin antagonists.
2-Other non hormonal measures eg mechanical :local spermicidal ,
barriers ,intrauterine devices, surgial.
3-physiological: safe period,lactation, coitus interaption
4- Hormonal: Implantation[norgesterel] for1 year or 3 years
Parentral[ medroxyprogesteron"depopro vera"]for 3
months just after labour , 1month injectable (mesigyna) .
Oral contraceptive pills:
: combined or progesterone only.
1-Progestrin only contraceptive pills:
-They include:
*Daily short acting small dose progestrin tablets: norethindrone
*Long acting depot progestrin injections or implants:
medroxyprogesterone
acetate injection or implants.
Mechanism of action:
-Inhibition of ovulation
-Inhibition of sperm penetration in the uterus due to increase viscosity of
cervical mucous.
-endometrial change
[For 30 day not stop,effective as IUD,indicated in obese, lactating , over
40 ,hypertention , thromboembolism]
Advantages:
-Contraception with progestins is useful in patients with hepatic disease,
hypertension (less hypertension than combined pills), psychosis or
mental retardation, or prior thromboembolism
-They do not suppress lactation. They can be used in lactating women
Disadvantages:
-Long term progestrin injection are not desirable for women planning a
pregnancy soon after cessation of therapy because ovulation suppression
can sometimes persist for as long as 18 months after the last injection
- Almost all users experience episodes of unpredictable spotting and
bleeding, particularly during the first year of use. Spotting and bleeding
decrease with time, and amenorrhea is common
Side effects:
The side effects include headache, dizziness, bloating and weight gain of
1–2 kg, and a reversible reduction of glucose tolerance , depression, acne.
2-Combined contraceptive pills
a. postcoital b. monthly
a. Postcoital contraceptive pills: through 72 h of coitus,2
tab./twice/5days
ethinyl estradiol+norgestrerl or stilbesteron
Pregnancy can be prevented following coitus by the administration of
estrogens alone, progestin alone, or in combination ("morning after"
contraception), when treatment begins within 72 hours,
Mechanism of action:
1-: increases uterine motility.
2-Progestrins interferes with implantation of ovum by changing the
structure of endometriam.
3-Withdrawal bleeding occur at the end of the course .
Disadvantages:
1-High incidence of side effects mainly nausea ,vomiting headache
headache, dizziness, breast tenderness, and abdominal and leg cramps. .
The hormones are often administered with antiemetics,.
2-The high doses of hormones used in this type of contraceptives are
teratogenic.If this type of contraception failed , therapeutic abortion
should be performed because of high incidence of fetal abnormalities.
3-Less effective than other types of contraception.
4-Mifepristone stops ovulation and may prevent pregnancy few
months after stoppage as a result of long action.
b. monthly
-They contain estrogen and progestrin .They are taken for 21 days
starting from the 5th day of the cycle and are omitted for 7days.
-Monophastic pills containing higher estrogen contents are 100%
effective.
It the woman forgets one pill,she has to take two pills on the next day.
-On the other hand ommition of one of the biphasic or triphasic pills (low
estrogen content) leads to loss of protection.
Triphasic contraceptive pills are taken according to the following
schedule:
 6 days :0.03 mg estrogen + 0.05 mg progestin.
 5 days :0.04 mg estrogen + 0.075 mg progestin.
 10 days:0.03 mg estrogen +0.125 mg progestin.
-This method has low incidence of break through bleeding and
thromboembolic disorders.
Mechanism of action:
*Estrogen inhibits FSH and progestrins inhibit LH.
*Producing thick mucus from the cervical glands and hence imending the
penetration of sperm cells into the uterus.
*Impending the transfer of the ovum so preventing implantation of the
fertilized ovum should fertilization take place.
Disadvantages &Side effects:
Mild side effects :nausea , breast tenderness, edema , weight gain
,headache ,migraine ,irritability ,breakthrough bleeding , loss of libido
,skin pigmentation and acne.
Severe side effects: Thromboembolic diseases,hypertension ,myocardial
infarction , cholestatic jaundice , cholecystasis , gall stones ,severe
depression and impaired glucose tolerance.
Advantages :
1-Reduced menstrual blood and thus less iron deficiency anemia.
2-Reduced incidence of menorrhagia and irregular bleeding.
3-Lower incidence of breast and endometrial cancers.
4-Less incidence of salpingitis and increase bone density.
Contraindications:
Thromboembolic diseases, diabetes mellitus, hypertension, congestive
heart failure, patients above 35 years of age, undiagnosed vaginal
bleeding ,cancer breast and fibroids ,liver diseases.
Drug interactions:
1. Drugs decrease contraception effect:
 Enzyme inducers as phenbarbitone, phenytoin & rifampicin.
 Mineral oils decrease pills absorption.
2. Pills decrease effect of other drugs:
 Oral anticoagulants.
 Insulin & oral hypoglycemics.
 Antihypertensives.
 Antihypercholesterolemics.
1.Drugs increase side effects of pills:
 Aminocaproic acid and tobacco smoking increase incidence of
thromboembolic disorders.
Uses of contraceptive pills:
 Contraception.
 Suppression of lactation: 3 pills/day for 7 days. Better use
the dopamine agonist bromocriptine.
 Amenorrhea: induction of artificial cycle [ menopause].
 Dysfunctional uterine bleeding.
 Endometriosis.
 To postpone menstruation e.g during pilgrimage.
Preparations of Oral combined Contraceptive pills
Estrogen (mg)
Progestin (mg)
Monophasic combination tablets
Alesse, Aviane, Lessinea,
Levlite
Ethinyl estradiol
0.02 L-Norgestrel
0.1
Levlen, Levora, Nordette,
Portia
Ethinyl estradiol
0.03 L-Norgestrel
0.15
Crysella, Lo-Ovral, LowOgestrel
Ethinyl estradiol
0.03 Norgestrel
0.30
Ethinyl estradiol
0.03 Drospirenone
3.0
Ethinyl estradiol
0.035 Norethindrone
1.0
Ethinyl estradiol
0.035 Norgestimate
0.25
Ethinyl estradiol
0.035 Norethindrone
1.0
Ovcon-35
Ethinyl estradiol
0.035 Norethindrone
0.4
Demulen 1/50, Zovia 1/50E
Ethinyl estradiol
0.05 Ethynodiol
diacetate
1.0
Ovcon 50
Ethinyl estradiol
0.05 Norethindrone
1.0
Yasmin
Brevicon, Modicon, Necon
0.5/35, Nortrel 0.5/35
Ortho-Cyclen, Sprintec
Necon 1/35, Norinyl 1+,
Nortrel 1/35, Ortho-Novum
1/35
Ovral-28
Ethinyl estradiol
Norinyl 1/50, Ortho-Novum Mestranol
1/50
0.05 D,L-Norgestrel
0.5
0.05 Norethindrone
1.0
Biphasic combination tablets
Ortho-Novum 10/11, Necon 10/11
Days 1–10
Ethinyl estradiol
0.035 Norethindrone
0.5
Days 11–21
Ethinyl estradiol
0.035 Norethindrone
1.0
Triphasic combination tablets
Enpresse, Triphasil, Tri-Levlen, Trivora
Days 1–6
Ethinyl estradiol
0.03 L-Norgestrel
0.05
Days 7–11
Ethinyl estradiol
0.04 L-Norgestrel
0.075
Days 12–21
Ethinyl estradiol
0.03 L-Norgestrel
0.125
Days 1–7
Ethinyl estradiol
0.035 Norgestimate
0.18
Days 8–14
Ethinyl estradiol
0.035 Norgestimate
0.215
Days 15–21
Ethinyl estradiol
0.035 Norgestimate
0.25
Ortho-Tri-Cyclen
Preparations of progestrin only
contraceptive pills
Progestrin
Dose
Norethindrone
0.35
Ovrette
D,L-Norgestrel
0.075
Implanon
Etonogestrel (one tube of 68 mg)
Nora-BE, Nor-QD, Ortho Micronor, Jolivette,
Camila, Errin
3-Postcoital contraceptive pills:
Pregnancy can be prevented following coitus by the administration of
estrogens alone, progestin alone, or in combination ("morning after"
contraception), when treatment begins within 72 hours,
Mechanism of action:
1-Estrogen and progesterone antagonists : increases uterine motility.
2-Progestrins interferes with implantation of ovum by changing the
structure of endometriam.
3-Withdrawal bleeding occur at the end of the course .
Disadvantages:
1-High incidence of side effects mainly nausea ,vomiting headache
headache, dizziness, breast tenderness, and abdominal and leg cramps. .
The hormones are often administered with antiemetics,.
2-The high doses of hormones used in this type of contraceptives are
teratogenic.If this type of contraception failed , therapeutic abortion
should be performed because of high incidence of fetal abnormalities.
3-Less effective than other types of contraception.
4-Mifepristone stops ovulation and may prevent pregnancy few months
after stoppage as a result of long action.
Referenecs:
Lippincott 5th Edition
goodman
Table 40–4 Schedules for Use of Postcoital Contraceptives.
Conjugated estrogens: 10 mg three times daily for 5 days
Ethinyl estradiol: 2.5 mg twice daily for 5 days
Diethylstilbestrol: 50 mg daily for 5 days
Mifepristone: 600 mg once with misoprostol, 400 mcg once1
L-Norgestrel: 0.75 mg twice daily for 1 day (eg, Plan B2)
Norgestrel, 0.5 mg, with ethinyl estradiol, 0.05 mg (eg, Ovral, Preven2): Two tablets
and then two in 12 hours