Are multiple pregnancies riskier than single pregnancies?
While the great majority of multiple pregnancies result in healthy babies, any pregnancy with twins or more is considered high risk. And the more babies you're carrying, the higher your risk of complications. The greatest risk is that you'll deliver the babies prematurely, which increases their chances of health problems.
What are the chances that I'll deliver prematurely?
According to the March of Dimes, close to 60 percent of all twins and more than 90 percent of triplets are born prematurely (before 37 weeks). The average twin pregnancy lasts 35 weeks. Triplet pregnancies average 33 weeks, and quad pregnancies average 29 weeks.
What are the risks of premature birth?
Babies born before their time may not be completely ready for the outside world. Their lungs, brain, and other organs may not be fully developed, their immune system may not be ready to fight off infections, and they may not be able to suck or swallow.
The earlier a baby is born, the greater the risks. Premature babies born between 34 and 37 weeks generally do very well. Babies born before 28 weeks may survive, but they'll need intensive medical care and a little luck.
If you go into labor before 34 weeks, your medical team may be able to delay your labor for a few days. They'll use this extra time to treat your babies with corticosteroids, drugs that help a baby's lungs and other organs develop faster to greatly increase the chances of survival. Your babies may also receive magnesium sulfate, which helps reduce the risk that they'll develop cerebral palsy.
What are other potential complications of having multiples?
Aside from preterm labor, there are several possible problems:
- Twins and triplets often don't have a chance to reach a healthy weight before they're born. While the average single baby weighs 7 pounds at birth, the average twin weighs 5.5 pounds. Triplets typically weigh 4 pounds each, and quads weigh 3 pounds each. Babies born at under 5.5 pounds are considered to have a low birth weight.
Babies with low birth weights are likely to have health problems even if they weren't born prematurely. Low-birth-weight babies often have trouble breathing on their own. They may not be fully prepared to fight infections, control their body temperature, or put on weight.
For these reasons, almost all low-birth weight babies have to spend time in a neonatal intensive care unit before going home.
- Preeclampsia is a serious condition characterized by high blood pressure and protein in the urine, or kidney or liver abnormalities. It develops in roughly 10 to 15 percent of women carrying twins, two to three times the rate of women carrying one baby.
The condition tends to develop earlier as well. And once it starts, it can be especially severe. When preeclampsia is severe, it can affect many of your organs and your placenta and cause serious or even life-threatening problems.
- Gestational diabetes is more common in women carrying more than one baby. If you develop gestational diabetes, your practitioner will monitor you closely. You'll most likely be able to keep your blood sugar levels under control with diet and exercise, but some women will require insulin shots or pills as well. Poorly controlled diabetes can have serious consequences for you and your babies.
- Placental abruption, when the placenta detaches from the uterine wall before delivery, is also more likely when you're carrying more than one baby. It can happen any time in the second half of pregnancy and can lead to growth problems, preterm delivery, or stillbirth. In multiple pregnancies, abruption may occur just after the first baby has been delivered vaginally. Once abruption has occurred, the other baby or babies may have to be delivered by cesarean section.
- Twin-to-twin transfusion syndrome is a rare but serious complication that occurs in identical twins when blood flows from one baby to the other through their shared placenta. According to the March of Dimes, 10 to 15 percent of identical twins develop the syndrome. The condition can be treated by using laser surgery to seal off the connection between the babies' blood vessels.
Will I be put on bedrest?
Your practitioner may put you on bedrest, especially if you develop complications such as preterm labor. There's no proof that bedrest can actually prevent premature delivery for women carrying multiple babies, but there are some situations where it may be beneficial to reduce your physical activity or take frequent breaks off your feet. If your practitioner recommends it, ask her to discuss the pros and cons with you.
Also, find out exactly what you can and can't do and for how long. Bedrest can mean anything from curtailing your activities to literally not getting out of bed for any reason. Even if your pregnancy is going smoothly, most doctors and midwives advise taking it easy beginning early in the third trimester.
What are the chances that I'll lose one or more of the babies?
When a woman is carrying twins, one baby might miscarry early in pregnancy while the other stays in place. This situation — called a vanishing twin — occurs in about 20 percent of all twin pregnancies. If you're carrying triplets, there's a 40 percent chance that one or more will miscarry in the first half of pregnancy.
In the days before ultrasound, these miscarriages went largely unnoticed. The only symptom is vaginal bleeding, and the remaining baby (or babies) usually develops normally.
Stillbirths — the loss of a baby after 20 weeks — are slightly more common in multiple pregnancies, but they're still rare. Only about 1 to 2 percent of twins or triplets are stillborn, compared with about 0.5 percent of singletons.
Some babies are lost at the end of a pregnancy and are delivered along with the surviving baby. In rare cases, a stillborn twin can be delivered several weeks before the surviving twin.
If you're carrying identical twins who are sharing a placenta, the loss of one twin after the 20th week can be very dangerous to the surviving baby. If your babies don't share a placenta, there's a good chance that your remaining baby can develop normally.
In either case, your practitioner will likely take a "watch and see" approach. If your remaining baby isn't in immediate distress, there's usually no reason to induce delivery early.
What can I do to reduce my risk of problems?
While many complications of twin pregnancies have little to do with your behavior or lifestyle, getting early confirmation that you are indeed carrying twins will give your healthcare provider plenty of time to catch and treat any complications that may crop up.
Educate yourself about the most common risks and complications of twin pregnancies, but don't obsess about all the things that can go wrong. Become familiar with the warning signs of preterm labor. Make sure you are well nourished and well hydrated. Finally, don't miss any prenatal appointments and make sure to follow your provider's instructions.