Not necessarily. The main thing to avoid is contraceptives that
contain estrogen, which can reduce your milk supply. So women who are
exclusively breastfeeding need to steer clear of birth-control pills
that contain both estrogen and progestin, as well as the Patch (a
bandagelike square that delivers hormones into your bloodstream) and
the Ring (which you insert into your vagina, where it releases
hormones).

Instead, you could use a "mini-Pill" — a progestin-only
contraceptive, such as Micronor, that won’t affect milk supply. (One
caveat: It’s important to take the mini-Pill at the same time every day
for optimal effectiveness.)

You can also safely use an intrauterine contraceptive (IUC) or
try any barrier method, such as a diaphragm, cervical cap, sponge,
condom, and Leah’s Shield (a reusable rubber insert), says Karen
Meckstroth, M.D., assistant clinical professor of obstetrics and
gynecology at the University of California, San Francisco.

I’m not sure whether I’m done having babies, so what’s long-term but not permanent?

An IUC is ideal, and there are two types. The first, the Mirena
IUC, releases a steady stream of progestin and is the most popular
birth control with female ob-gyns.

It’s even more effective than tubal ligation if it stays in
place, says Dr. Meckstroth. It most likely works by changing the
texture of cervical mucus so that it blocks sperm from reaching the
eggs. It can also prevent ovulation. It’s approved for up to five
years, and once it’s removed you can get pregnant right away.

There’s also ParaGard, an IUC that’s approved for up to ten
years and doesn’t use hormones. It releases copper instead, which
experts think creates an environment that’s toxic to sperm. It may also
keep the egg from attaching to the uterus.

Another option: Implanon, a matchstick-size rod that’s
implanted under the skin of your arm to release progestin and lasts for
up to three years. One downside: It often causes breakthrough bleeding,
so you’d have to be willing to put up with that.

I’ve heard there’s a type of sterilization for women that isn’t surgical. Does it work? Is it permanent?

It’s called Essure, and it’s put in via a nonsurgical procedure
that can be done in your doctor’s office. A pluglike coil is inserted
through your cervix into each fallopian tube. Over time, tissue grows
over the devices, permanently blocking the tubes and keeping sperm out.
Until the tissue is fully formed, you can’t rely on it, so you’ll have
to use a backup method the first three months post-insertion. It seems
to be as effective as tubal ligation and has a faster recovery, but its
efficacy hasn’t been studied beyond ten years. You should also assume
it’s not reversible, says Daniel Mishell, M.D., chairman of obstetrics
and gynecology at the Keck School of Medicine at the University of
Southern California, in Los Angeles.

My husband got a vasectomy after our first child, but now we want to have more. Is it really permanent?

It can be reversed, but it’s pricey (from $6,800 to $13,000) and
the success rate is only 30 to 40 percent. Another option to consider:
A physician can use a needle to remove sperm from the testicles and
then perform in vitro fertilization.

Oral contraceptives Most pills are safe to use after the first
month postpartum (when the risk of blood clots decreases). Since most
also contain estrogen, which may reduce breast-milk production, a
better choice for nursing moms is the progestin-only mini-pill.

The patch and the ring Since these methods contain the same
hormones as birth-control pills, the same cautions apply. But with
effectiveness similar to the Pill’s and even greater ease of use,
they’re good options.

The IUD A choice for new moms (women who haven’t had a baby are
more likely to expel the device), the IUD releases progesterone, which
doesn’t interfere with breastfeeding and results in lighter menstrual
periods. It’s as effective as sterilization, can be inserted about four
to six weeks after delivery, and lasts up to five years.

Barrier methods Diaphragm users need to be fitted for a new one
after delivery. Condoms are still a reliable and inexpensive choice,
but forget cervical cups and the Sponge  — they don’t provide enough
protection in women who have given birth.

Sterilization If this pregnancy is your last, sterilization can
be performed at delivery. But be sure it’s what you want  — the
procedure is difficult to reverse.