Over the past two decades, there's been a phenomenal rise in
the number of multiple births in the United States. Between 1980
and 2004, the number of twin births increased by 70% and the number
of births involving three or more babies has quadrupled.
What's responsible for this dramatic rise in multiple
births? And how should you prepare for your own multiple birth
experience?
The Miracle of Multiples
Several factors contribute to the development of a multiple
pregnancy:
-
Heredity:
A history of multiple births on a woman's side of the family
increases her chances of having a multiple pregnancy.
-
Race:
Women of African descent are the most likely to have multiple
pregnancies.
-
Number of prior pregnancies:
Having more than one previous pregnancy, especially a multiple
pregnancy, increases the chance of having a multiple
pregnancy.
-
Delayed childbearing:
Older women who get pregnant are more likely to have
multiples.
-
Infertility treatment:
Fertility drugs, which stimulate the ovaries to release multiple
eggs, or assisted reproductive technology (ART), which transfers
multiple embryos into the womb (such as in vitro fertilization,
or IVF), greatly increase a woman's chance of having a
multiple pregnancy.
It's the last two factors that have been on the rise in the
last couple of decades and are probably responsible for the
increase in multiple births.
The Types of Multiples
There are two types of twins:
monozygotic
(identical) and
dizygotic
(fraternal).
Identical twins
result from a single fertilized egg dividing into separate halves
and continuing to develop into two separate but identical babies.
These twins are
genetically
identical, with the same chromosomes and similar physical
characteristics. They're the same sex and have the same blood
type, hair, and eye color.
Fraternal twins
come from two eggs that are fertilized by two separate sperm and
are no more alike than other siblings born to the same parents.
They may or may not be the same sex. This type of twins is much
more common, and only this type is affected by heredity, maternal
age, race, and number of prior pregnancies.
"Supertwins"
is a common term for triplets and other higher-order multiple
births, such as quadruplets or quintuplets. These babies can be
identical, fraternal, or a combination of both. But higher-order
births are rare; triplets occur in approximately 1 in 7,000 to
8,000 births, whereas quintuplets are likely to be born only once
in 47 million births.
The Risks of Multiple Births
The most immediate risk involved with multiple births is
pre-term (or early) labor resulting in
premature
births. A typical, single pregnancy lasts about 40 weeks, but a
twin pregnancy often lasts between 35 to 37 weeks. Nearly half of
all twins are born prematurely (before 37 weeks), and the risk of
having a premature delivery increases with higher-order
multiples.
Premature babies (preemies) can have
numerous health challenges
. Because the care of premature babies is so different from that of
full-term infants, preemies are usually placed in a
neonatal intensive care unit (NICU)
after delivery. The risk of developing health problems increases
with the degree of prematurity - babies born closer to their due
date have a lower risk.
In addition to the possibility of premature births, other
medical conditions that are more likely to occur during a multiple
pregnancy include preeclampsia, gestational diabetes, placental
problems, and fetal growth problems. Being part of a multiple birth
can also be associated with long-term health problems in the
infants. Developmental delays and
cerebral palsy
occur more commonly in twins than in single births, and there's
a higher risk of enduring health problems with higher-order
multiple births.
Because of these concerns, many doctors who specialize in
fertility treatments require prospective parents to undergo
intensive counseling on the possibilities and risks associated with
multiple births.
Staying Healthy During a Multiple Pregnancy
Eating properly, getting enough rest, and making regular trips
to the doctor are critical measures for any expectant mother to
stay healthy
. And a woman with a multiple pregnancy might be scheduled for more
frequent appointments with her obstetrician/gynecologist (OB-GYN)
than a women who is pregnant with a single fetus.
The need for frequent, intensive prenatal care is of the utmost
importance in a multiple pregnancy. You'll want to be
particularly careful about finding health care professionals who
have experience with multiple births. Because multiple pregnancies
are automatically termed high-risk, the need for specialized health
care is vital to ensuring that you and your babies receive the best
care available.
Because you may not know anyone who has experienced a multiple
birth, asking for a referral from a friend may not be productive.
Instead, ask your doctor or OB-GYN to recommend a facility that
specializes in multiple births. You should be part of a pre-term
birth prevention program at your hospital and have immediate access
to a specialized NICU should you go into early labor or if one of
your babies is
born with a health problem
.
Your Nutrition
If you're pregnant with multiples, you should follow general
pregnancy nutrition guidelines, including increasing your calcium
and folic acid intake. Pregnant women need additional calcium, so
extra milk or fortified orange juice, broccoli, sardines, or other
calcium-rich foods should be added to your diet.
As with all expectant mothers,
folic acid
is extremely important. Taking folic acid 1 month prior to and
throughout the first 3 months of pregnancy will decrease the risk
of neural tube defects (such as
spina bifida
).
Another dietary requirement that needs to be increased if
you're expecting more than one baby is protein, which has
several important functions. First, proteins serve as the building
materials of body tissue. They also act as enzymes that regulate
chemical reactions to keep a body growing and functioning.
During pregnancy, an increased supply of iron is also needed for
hemoglobin, the substance in red blood cells that binds oxygen for
delivery to the tissues. Insufficient iron can lead to a condition
known as
iron-deficiency anemia
. Anemia occurs when the number of healthy red blood cells
decreases in the body), and is relatively common in multiple
pregnancies. Anemia can cause a decreased appetite and extreme
fatigue during a pregnancy, as well as a reduced oxygen supply to
the developing babies. Your doctor will probably prescribe an iron
supplement, as your requirement for this mineral usually can't
be met by diet alone.
Iron is absorbed more easily when combined with foods high in
acid, such as yogurt, and those with high amounts of vitamin C,
like orange juice.
Additional fetuses also mean an increased need for all other
nutrients (such as zinc, copper, vitamin C, and vitamin D). So
it's important to take your prenatal vitamin supplement every
day. But just because you're carrying more than one baby
doesn't mean you should take more than one prenatal vitamin -
one is enough and too much can even be harmful.
Your Weight
Mothers carrying multiples are expected to gain more weight
during pregnancy than mothers carrying a single fetus. But exactly
how much weight you should gain depends on your pre-pregnancy
weight and the number of fetuses, so make sure to talk to your
doctor. In general, though, you should consume about 300 additional
calories a day for each fetus. Although it might be tough to eat a
lot when your abdomen is full of babies, it can help to eat
smaller, more frequent meals.
Your Comfort
Of course, expecting multiples means that you're probably
experiencing the typical discomforts of pregnancy more intensely.
Nurturing yourself can help ease the stress of pregnancy. Even a
warm bath can help lift your spirits. (Just make sure you have
someone around to help lift you out of the tub!)
Expectant partners can help, too. Something as simple as having
someone brush your hair can make the discomforts of pregnancy fade
momentarily. It helps, too, if your partner remembers that your
body is going through tremendous hormonal changes. Communication
and understanding can be the keys to truly enjoying this special
time in your lives.
Preparing for Childbirth
Getting ready for a multiple birth may seem overwhelming, and
concerns about pre-term labor can be additional burdens for you to
bear. The best reassurance is knowing that you have a network of
support around you: capable doctors, a caring hospital staff, and
hopefully a supportive partner, family members, and/or friends.
To help you be more comfortable with the birth process as it
unfolds, you should also discuss the options of vaginal delivery
versus
cesarean section (C-section)
with your doctor well before your due date. Several factors affect
the safety of each approach. Even if you and your doctor agree to
attempt a vaginal delivery, circumstances may arise during labor or
delivery that make a C-section necessary.
You may opt to have additional birthing attendants in the room
during labor and birth. For example,
midwives
are becoming more common. Working in collaboration with a medical
doctor, a certified nurse-midwife (CNM) has specialized training in
midwifery and is registered or licensed in all 50 states.
Hiring a doula is another option. The term comes from ancient
Greece, where the doula was the primary attendant to the female
head of the household. Today, doulas offer support services to
women during the birth, as well as after delivery, by assisting
with infant care and household chores.
Special Delivery
As labor begins, you'll likely be connected to a fetal
monitor so your doctor can check each baby's progress. The
interval between the birth of each baby delivered vaginally is
usually less than an hour. And here's one piece of good news:
Because multiple-birth babies tend to be smaller than single ones,
it's easier to push them out. Luckily, they only come out one
at a time!
In the case of multiples, though, a vaginal delivery may not
always be possible. The crowded uterus can cause compression of the
placenta or umbilical cord of any of the soon-to-be-born babies
during labor. Prolonged compression may put one or more babies at
serious risk as labor progresses during attempts at vaginal
delivery. So prompt delivery by C-section may be necessary in these
cases.
Positioning of the babies can also affect the safety of a
vaginal delivery. It's common for the first baby to be born
head first, whereas the subsequent infants may be breech (buttocks
or feet first), transverse (sideways), or head first when entering
the birth canal. Usually, if the first fetus is not head first, the
babies will be delivered by C-section. And most triplets and other
higher-order multiples are born by C-section.
If your doctor needs to perform a C-section, a catheter will be
placed in your bladder, you'll be given anesthesia, and an
incision will be made in your abdomen and uterus. The doctor will
then deliver your babies through the incision. The babies will be
delivered within just a few minutes of each other with this
approach.
If you go into labor prematurely, you and your unborn babies
will be closely monitored for signs of distress. You may have to
make decisions on the delivery method and procedures at this time,
so take time to consider your options before arriving at the
hospital. Many babies born prematurely will need to go immediately
to the NICU for the special care they need. Visitations by family
members are usually encouraged, often right from the
first day
.
Taking Your Babies Home
The first days, weeks, and months are often the most difficult
for parents of multiples, as everyone learns to get used to the
frequent feedings, lack of sleep, and little personal time involved
in
parenting multiples
. Enlist whatever help you can get - from neighbors, family
members, and friends - for household chores and daily tasks. Having
extra hands around can not only make feedings easier and help you
rest and
recover from delivery
, it can also give you the precious time you need to get to know
your babies.
Reviewed by:
Elana Pearl Ben-Joseph, MD
Date reviewed: October 2007
Note: All information is for educational purposes only. For specific medical advice,
diagnoses, and treatment, consult your doctor.
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