Types of pills
generation oral contraceptives
products containing 50΅g or more of ethinyl estradiol (EE).
Second generation oral contraceptives
products containing 30-35΅g of EE and
levonorgestrel (LNG) or norgestimate or other members of norethindrone
Third generation oral contraceptives
products containing 20 or 30΅g EE and
desogestrel or gestodene.
Pills may also be categorized based on the
amount of ethinyl estradiol :
high dose oral contraceptives
are pills containing 50΅g or more of EE.
low dose oral contraceptives
include pills containing 30-50΅g of EE.
Ultra low dose oral
contraceptives are pills containing less then 30΅g of EE.
5.2 Mechanism of action
inhibit ovulation by inhibiting gonadotrophin secretion via an effect
on both pituitary and hypothalamic centers. The progestational agents
suppress LH and estrogens suppress FSH.
in addition, the progestational agent
also makes the endometrium unsuitable for implantation and thickens
cervical mucus making it impervious to sperm.
early reversibility of fertility
does not interfere with sexual activity
no menstrual irregularity
can be used in nullipara
protects against benign breast diseases,
pelvic inflammatory diseases, ovarian cysts, ovarian and endometrial
decreases menstrual blood loss and prevents
iron deficiency anaemia.
suitable for clients with history of
client can discontinue use anytime on
her own unlike intrauterine device and norplant which necessitate
a visit to the health-care provider.
patient compliance is required.
not suitable in lactating mothers
no protection against sexually-transmitted
diseases or AIDS
unacceptable to some clients due to
minor side-effects like nausea, vomiting, breast tenderness, headache,
5.5 Contraindications for
low dose COCs
mothers up to 6 months post-partum
up to 3 weeks post-partum in non breast-feeding
more than 35 years of age with risk
factors for cardiovascular disease e.g. hypertension, smoking,
vascular disease etc.
history of deep vein thrombosis/pulmonary
patient undergoing major surgery with
current and past history of cardiovascular
valvular heart disease with superimposed
complications like pulmonary artery hypertension and atrial fibrillation.
history of migraine with focal neurological
symptoms at any age
current or past history of breast cancer
diabetes mellitus with complications
like neuropathy and retinopathy
current gall bladder disease or history
of jaundice related with use of combined oral contraceptives
active liver disease or cirrhosis
benign or malignant tumors of the ovary
patients on drugs likely to affect metabolism
of the COCs e.g. Rifampicin, griseofulvin, phenytoin, barbiturates
Conditions when COCs can be prescribed under
supervision include :
breast-feeding women more than 6 months
history of gestational diabetes, cholestasis
in pregnancy or pregnancy-induced hypertension
women under 35 years of age with risk
factors for cardiovascular disease
history of cholecystectomy
age > 40 years
superficial venous thrombophebitis
uncomplicated valvular heart disease
unexplained vaginal bleeding
cervical intraepithelial neoplasia and
cervical cancer awaiting treatment
diabetes mellitus (well controlled)
with no vascular disease
5.6 Drug interactions
which stimulate the livers metabolic capacity can affect efficacy
of both low and high dose COCs to some extent. Patients on medications
(listed below) should be counseled to choose an alternative method
It was previously thought that antibiotics
which reduce the bacterial flora of the gastrointestinal tract e.g.
ampicillin, tetracycline decrease the efficacy of COCs. Studies
have now indicated that antibiotics can alter the excretion of contraceptive
steroids but plasma levels are unchanged, and there is no evidence
Substantial evidence indicates that COCs
potentiate the action of diazepam, chlordiazepoxide, tricyclic antidepressants
and theophyline6. Thus, lower doses of these agents may
be effective in COC users. On the other hand, COC users may require
larger doses of acetaminophen and aspirin7.
5.6 When to start COC pills
COCs can be started on any day within
the first five days of menstrual bleeding, preferably on the first
day . It may be started between 5-14 days of menstrual cycle (if
the woman has not had unprotected sex in that cycle and pregnancy
is excluded) with an additional contraceptive method like condom
or spermicide for the next seven days. Patient should be warned
of a change in menstrual pattern.
to six weeks after childbirth in non-lactating mothers. If started
later than 6 weeks, pregnancy should be ruled out.
first 7 days of a first or second trimester abortion.
after stopping any other contraceptive method.
5.7 Instructions to the
the client should be instructed to take one pill every day at
the same time and link it with a routine daily activity to help
if provided with 28 pill packet, she
should start another packet from the very next day without any
if provided with 21 pill packet, she
should wait for 7 days after finishing the pack and then start
the first pill from the next packet. It should be emphasized that
a gap of more than 7 days will decrease the efficacy of COCs.
5.8 Instructions to the patient
of missed pill
if one white pill is missed, she should
take that pill as soon as she remembers and the next pill on the
usual time. No additional contraceptive method is required.
if she misses 2 pills in the first two
weeks, she should take two pills on each of the next two days
and an additional method is to be used for next 7 days.
if she misses two pills in the third
week, or more than 2 active pills are missed at any time, then
a new packet has to be started on the same day and an additional
contraceptive method to be used for 7 days .
if she misses one brown tablet then
she should throw the missed pill and take rest of the tablets
Note : Even if no pills are missed,
woman should be instructed to use a back-up method for 7 days
after an episode of gastroenteritis.
If unprotected sex has taken place, after missing pills
emergency contraception should be prescribed.