What birth control methods take the shortest and longest time to work?

How long does it take for birth control to work?

Zawn Villines
by Debra Rose Wilson, PhD, MSN, RN, IBCLC, AHN-BC, CHT
Some birth control methods,
such as condoms, diaphragms, and other barrier options, work right away. Birth
control that makes chemical or physical changes to the body often takes longer,

A person should ask their
doctor if they need to abstain from intercourse, and how likely a pregnancy is,
both before and after a birth control method reaches its full effectiveness.
How long it takes a birth
control method to begin working, depends on how it prevents pregnancy. Condoms,
for example, provide birth control by preventing semen from entering the
vagina. These and other barrier methods work immediately.

Fast facts on how long birth
control takes to work:

  • The time it takes to work
    depends on the type, when it is used, and personal factors.
  • Methods that work by
    preventing ovulation can take several days to become effective.
  • No birth control method works
    100 percent of the time for everyone.
  • Each method can also cause
    side effects that vary with overall health and individual lifestyle.
How long does birth control
take to work?
There are at least two ways to
measure the effectiveness of birth control.
Correct or perfect use tells
how effective a method is when it is used exactly, as recommended, every time.
Typical use is a measure of how effective birth control is with the normal
level of error most users experience.

Methods and timeframes

The effectiveness of various
methods, as well as how long they take to work, is as follows:
Oral contraceptives

When they are used correctly,
for example, taken daily, without missing a dose, oral contraceptives are 99
percent effective.
At typical usage rates,
including being taken incorrectly at times, these drugs are 91 percent
The progestin-only pill
contains a hormone called progestin. This hormone thickens cervical mucus,
making it more difficult for sperm to travel to an egg. It can also prevent
If the first pill is taken
within the first 5 days of the start of a woman’s menstrual cycle, in other
words, the first day of her period, it works immediately.
Women who have a cycle shorter
than 23 days, however, will need to wait 2 full days. When taking the first
dose later than 5 days after the first day of the cycle, these pills take 2
days to be effective.
Combination pills contain two
hormones that prevent ovulation. The first pill is taken on the Sunday
following a woman’s period. These pills take 7 days to become fully effective.
Intrauterine device

An intrauterine device (IUD)
is a small device inserted into the uterus. With typical usage, these devices
are more than 99 percent effective.
The copper IUD causes
inflammation in the uterus that kills sperm. It begins working immediately
after a doctor inserts it, and can remain effective for up to 12 years.
Hormonal IUDs such as Liletta, Mirena, and Skyla prevent ovulation with the
hormone progestin.
If inserted within 7 days of
the start of a woman’s period, these devices are effective immediately. When
they are inserted at any other time, they take 7 days to begin working.


Birth control implants are
tiny rods that a doctor inserts under a woman’s skin. They release progestin
and prevent ovulation. At typical usage rates, these devices are more than 99
percent effective.
When inserted during the first
5 days of a woman’s cycle, the implant works immediately. Otherwise, it takes 7
days to reach full effectiveness.


The birth control patch gives
the body a dose of estrogen and progestin. Together, these hormones prevent the
body from ovulating. A woman must apply a new patch each week, except during
the week she gets her period.
The success rate is 91 percent
in most women, but in those who weigh more than 198 pounds, failure may be more
When the first patch is
applied within 5 days of the start of a woman’s period, it works immediately.
Otherwise, it takes 7 days to become effective.

Barrier methods

Barrier methods are methods
that stop sperm from coming into contact with an egg, so preventing
The male and female condoms
and the diaphragm each create a physical barrier. With typical use, diaphragms
are 88 percent effective. Female condoms are 79 percent effective, and male
condoms are 82 percent effective.
Spermicides create a barrier
by killing sperm. They are 72 percent effective with typical use.
Barrier methods begin working
Vaginal ring

The vaginal ring is a ring
inserted into the vagina that releases estrogen and progestin. Like other
hormonal methods, it prevents ovulation. A woman wears it for the first 3 weeks
of her cycle and then takes it out to have her period.
With typical usage, the
failure rate is 9 percent. If inserted on the first day of a woman’s cycle, it
works immediately. Otherwise, it takes 7 days to work.
Birth control injections

Birth control injections
require an injection of the hormone progestin every 3 months. With typical
usage, the success rate is 94 percent. The injection prevents ovulation. When
the injection is given within 5 days of the start of a woman’s period, it works
immediately. Otherwise, it takes 7 days.

A vasectomy prevents sperm
from getting into a man’s semen. He can still ejaculate, but the ejaculate will
not cause his partner to become pregnant. Initially, a man’s fertility declines
slowly and steadily following a vasectomy. For most men, there are no sperm in
the semen by the 12-week mark.
One study, however, found that
17 percent of men still have sperm at 24 weeks following surgery. So, it is
vital to continue testing semen with a doctor until it can be confirmed that
sperm are no longer present.
The success rate of vasectomy
is nearly 100 percent, as long as a man uses a backup method until a doctor
confirms that he is sterile.

Female sterilization

Two methods can permanently
sterilize a woman. Both are nearly 100 percent effective.
With transcervical
sterilization, a doctor inserts a tube into each fallopian tube. This irritates
the tubes, causing scar tissue that blocks the tubes and prevents an egg from
being able to move down the tube. Transcervical sterilization takes about 3
months to work.
A tubal ligation is
sterilization that also blocks the fallopian tubes but by surgically closing
them. It is effective immediately.


Hormonal birth control might
not be right for smokers and those with a history of blood clots, while sterilization
should be reserved only for people who are certain they do not want any more
It is advisable to talk to a
doctor about various options and to ask whether lifestyle or other factors will
influence the effectiveness of the method a person chooses.
Kayode Ojo
Kayode Emmanuel Ojo is the Co-Founder and Managing Director at SHEFFA Limited. He is presently studying Computer Science at the National Open University, Victoria Island, Lagos.