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Regular contractions may mean that your uterine muscle is
tightening (Braxton Hicks contractions) or that you are in labor. It may be
hard to tell the difference between Braxton Hicks contractions and true labor.
If there is any doubt, call your doctor.
During the second and
third trimesters of pregnancy, you may have episodes when your belly tightens
and becomes firm to the touch, then relaxes. These are episodes of tightening
(contraction) of the uterine muscles called Braxton Hicks contractions. These
normal contractions may be mild, or they may be strong enough to make you stop
what you are doing.
Braxton Hicks contractions can begin as early
as the 20th week of pregnancy, but most often they start between the 28th and
Braxton Hicks contractions can occur often during the
9th month, such as every 10 to 20 minutes.
The length of a normal pregnancy is 37
to 42 weeks, measured from the date of the woman's last menstrual period.
Preterm labor occurs before the 37th week of pregnancy. Before 20 weeks,
preterm labor that leads to delivery is a
miscarriage (spontaneous abortion).
Preterm labor is diagnosed in a woman who is 20 to 37 weeks pregnant and
has regular uterine contractions. This means 4 or more in 20 minutes, or about
8 or more in 1 hour.
Call your doctor if you have had regular
contractions for an hour, even after you have had a glass of water and are
Early labor is often the longest part of
the birthing process, sometimes lasting 2 to 3 days. Uterine
In early labor, the
cervix opens (dilates) to about
3 cm (1.2 in.).
First-time mothers may have many hours of early labor without the cervix
dilating. You may go to the hospital and be sent home again until you begin
active labor or your water breaks (rupture of the membranes).
The first stage of active labor starts
when the cervix is about
3 cm (1.2 in.) to
4 cm (1.6 in.) dilated. This stage is
complete when the cervix is fully dilated and the baby is ready to be pushed
out. During the last part of this stage (transition), labor becomes really
Compared to early labor, the contractions during the
first stage of labor:
You may feel restless or excited during active labor. Now
is the time to be at or go to the hospital or birthing center. If your bag of
waters (amniotic sac) has not broken before this, it may now.
If you have taken a labor class and learned how to do special breathing during
contractions, you will want to begin the special breathing now.
Current as of:
June 4, 2014
William H. Blahd, Jr., MD, FACEP - Emergency Medicine & H. Michael O'Connor, MD - Emergency Medicine
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