Twins, Triplets and Other Multiple Births

If you are pregnant with more than one baby, you are far from alone: multiple births have risen sharply in the United States. In 1980 there were 69,339 twin and 1,337 triplet births; in 2005, 133,122 twin babies and 6,208 triplet babies were born.

Why multiples are more common

• More women are having babies after 30. Women in their 30s are more likely than younger women to conceive more than one baby naturally.
• More women are using fertility drugs and treatments to help them conceive.
• Family history. Twins in the family also make multiples more likely.

How twins form

• Identical twins come from a single fertilized egg that splits in two. They look almost exactly alike and share exactly the same genes. Most happen by chance.
• Fraternal twins come from two separate eggs fertilized by two separate sperm. They share no more genes than any other siblings, and they tend to run in some families.

Multiple births can be fraternal, identical, or a mix. Multiples linked to fertility treatments are mainly fraternal.

Knowing early

Years ago most twins were a surprise. Thanks to advances in prenatal care, most women now learn early that they are carrying more than one baby. Stronger body changes can be a clue — rapid weight gain in the first trimester, intense nausea and vomiting, and extreme breast tenderness — and an ultrasound can confirm it.

Extra care

Women expecting multiples need to see their health care provider more often than women expecting one baby, because the risk of complications is higher. The risks include:

• preterm birth;
• low birth weight;
• preeclampsia;
• gestational diabetes;
• cesarean delivery — especially with three or more babies;
• a greater risk of disabilities for the babies.

Some women need bed rest to delay labour. More frequent visits let the provider watch over mother and babies and advise on weight gain, extra vitamins and how much activity is safe; with close monitoring, the babies have the best chance of being born near term at a healthy weight.

After the birth

Caring for multiples can be overwhelming and exhausting. Ask your partner, family and friends for help; volunteer help and support groups for parents of multiples can also make things easier.

Sources

• MedlinePlus, U.S. National Library of Medicine, "Twins, Triplets, Multiple Births," drawing on the Office on Women's Health. https://medlineplus.gov/twinstripletsmultiplebirths.html
• Office on Women's Health, U.S. Department of Health and Human Services, "Twins, triplets, and other multiples," used for the birth figures, the reasons, how twins form, early signs and the risks: https://womenshealth.gov/pregnancy/youre-pregnant-now-what/twins-triplets-and-other-multiples
• Rewritten in hubnx's own words.