CWC - Article on Twins

Twins

By: Bradley G. Goldberg, M.D.

Multiple gestation is the medical term that refers to a woman who is pregnant with twins, triplets, or other higher-order multiple pregnancies. This will occur in slightly less than 2% of all pregnancies. Within the category of multiple gestation, twin births are by far the most common, accounting for 95% of all multiple pregnancies.

Recently, there have been significant increases in the number of multiple births. In the last ten years, the number of twin births has increased by one-third, and the number of triplets, quadruplets, or higher has increased by a whopping 178%! As you can imagine, much of this increase is due to the widespread use of fertility drugs. Twins occur naturally about once every 90 pregnancies, while triplets occur naturally once every 10,000 pregnancies. However, both of these are much more common when fertility medications are used. Another reason for the increase in multiple pregnancies is due to the fact that many women are postponing childbirth until their thirties, without realizing that their likelihood of experiencing a multiple pregnancy increases until the age of 40.

Identical twins occur when one egg has been fertilized but then divides and develops into two babies. Fraternal twins occur when two separate eggs are fertilized. This is the type that tends to run in families, being more common in women who were fraternal twins themselves. It is also more common, accounting for almost 70% of all twin pregnancies. The remainder are identical twins. Sometimes the doctor can tell at birth if the twins are identical, but often you must wait to see if the children grow and develop like "two peas in a pod."

Although the first reaction of most people who find out that a friend or relative is pregnant with twins is: "oh, how cute," the fact is that twins and all multiple gestations are considered high-risk pregnancies. A woman pregnant with twins is at a much higher risk of numerous problems including preterm labor, blood-pressure problems, and problems with the placenta. We also must not forget the fact that carrying twins is usually much more uncomfortable for the woman.

The key to controlling these potential problems is to identify the twin pregnancy early in the process. Without the use of ultrasound, almost one-half of all twin pregnancies are undiagnosed until the delivery. When ultrasound is used, most twins will be identified early in the pregnancy, although up to 5% will still not be discovered until delivery.

When a twin pregnancy is diagnosed, your doctor will want to see you more frequently. Towards the end of your pregnancy, the doctor will run special tests on the babies on a weekly basis in order to assure that they are healthy. In addition, women who are pregnant with twins need to consume more calories per day than women with single pregnancies. Decreased physical activity will likely be recommended, especially towards the end of the pregnancy.

Another important issue for a woman pregnant with twins is how will the babies will be delivered. A vaginal delivery can be attempted almost one-half of the time. However, the remainder will be delivered by cesarean section. For the most part, the determining factor is the position of the babies at term, although other issues can be involved. When a woman is pregnant with three or more babies, the delivery should always be by cesarean section.

In summary, although the idea of a twin pregnancy is fun, we must not forget that it is actually a high-risk situation. However, with close monitoring by your physician, and certain daily lifestyle modifications, a good outcome is very likely.

Bibliography

1. Williams Obstetrics, 20^th Edition, F. Gary Cunningham,M.D. et.al., Appleton & Lange, Stamford, Connecticut, 1997.

2. Multiple Gestation, ACOG Technical Bulletin # 131, August 1989.

3. The Rising Number of Multiple Births, Vicki L. Seltzer, M.D., Woman’s Health, August 18, 1997.