Pregnancy always requires planning, but when a family is expecting twins, extra preparation and precautions are necessary. Twin pregnancies have special health and nutritional considerations, plus they come with an increased risk of complications. These concerns and the anticipation of raising two newborns can cause considerable anxiety; gaining a better understanding of what to expect and seeking out appropriate medical care early on can lead to healthier, safer outcomes for the mother and her children.

Odds of Having Twins

Twin pregnancy is relatively rare, making up only about 3.4% of live births. For about 30 years before 2009, twin births became much more common, mostly due to the increased availability of in vitro fertilization. However, practices regarding embryo transfer changed at the end of the last decade, and now most twin pregnancies are natural occurrences. Older women have a slightly higher chance of having twins or other multiples because hormonal changes can increase the chance that more than one egg is released at a time.

Discovering a Twin Pregnancy

Timely prenatal care is important, and most parents find out they’re having twins at one of these preliminary doctor visits. Even early in the pregnancy, at around seven or eight weeks, a medical professional may be able to detect two heartbeats. A sonogram will confirm the twin pregnancy because both babies are usually visible on the screen.

Different Types of Twin Pregnancies

In general, there are two types of twin pregnancies. Identical twins occur when a single fertilized egg splits. Identical twins will be the same sex and will look very much alike physically. Fraternal twins are more common. They occur when two separate eggs are fertilized by two separate sperm at the same time. Fraternal twins may be the same or different sexes and may or may not look alike.

Placentas and Amniotic Sacs

The placenta is an organ that develops in the uterus to provide oxygen and nutrients to the fetus and to remove waste. The amniotic sac is a fluid-filled membrane that protects the fetus during development. Fraternal twins always have their own placenta and amniotic sac. Identical twins may, and this is considered optimal. However, they may also share a placenta, or, rarely, share both the placenta and the amniotic sac, which can cause complications.

High-Risk Pregnancies

Even for a healthy mother, a twin pregnancy is always considered a high-risk pregnancy. The chances of experiencing a complication such as preeclampsia, pre-term birth, or C-section delivery are all higher with twin pregnancies. Consequently, a mother expecting twins needs to keep all prenatal appointments and follow instructions provided by her care team.

Prenatal Appointments

Usually, a mother pregnant with twins will need more prenatal doctor appointments than a woman carrying a single fetus. During each visit, the care team will check on the babies’ growth and development, monitor the mother’s health, and discuss any concerns regarding complications. Mothers expecting twins may also receive more frequent ultrasounds. In particular, doctors monitor pregnancies where the twins share a placenta more closely since this can affect growth.

Weight Gain

Generally, a woman of average weight should gain 25 to 35 pounds during a normal pregnancy. If expecting twins, however, the same women are advised to gain 37 to 54 pounds. For each developing fetus, a woman needs to take in about 300 additional calories each day, so during a twin pregnancy, a mother may consume around 600 additional calories.

Prenatal Vitamins

During any pregnancy, taking prenatal vitamins is important to meet the nutritional needs of both mother and baby. Folic acid is a particularly important ingredient in these vitamins since it prevents problems with the developing baby’s brain and spine. Mothers with twin pregnancies should take normal prenatal vitamins and may need extra folic acid. A physician may also recommend extra iron to prevent iron-deficiency anemia, which is more likely to occur when the mother is carrying more than one child.

Pregnancy Complications

While problems can occur during any pregnancy, mothers carrying twins may be at higher risk. It is important to be familiar with potential complications, including

• Preeclampsia: This blood pressure disorder usually occurs after 20 weeks in the pregnancy. It can cause organ damage or even death if untreated. Blood pressure checks at prenatal appointments can identify this risk early on.
• Gestational diabetes: Some women develop diabetes during pregnancy. It causes high blood sugar and can affect both the mother and babies’ health. A glucose tolerance test helps detect this condition.
• Preterm labor and birth: More than half of all twin births occur before full term. Babies born before they are full-term are at higher risk of both short- and long-term health problems.

Twin Pregnancy Delivery

Though some twin pregnancies are delivered after 37 weeks, which is considered full-term, a little more than half are delivered around 36 weeks. The chance that a woman will need a C-section is higher with twin pregnancies, but it is possible to deliver twins vaginally, depending on the position, weight, and health of each baby. The medical team also assesses the mother’s health and how labor is progressing to determine how delivery should continue. Generally, twin delivery will take place in an operating room as a safety precaution, even if a vaginal birth is planned.