Are Your Twins Fraternal Or Identical? For Me, I Got A Surprise!

                                Above: Lucas and Zachary Tesler, Dr. Deborah V. Tesler’s identical twins

Do you have twins whom at birth you were told were fraternal, only to find out that they are actually identical? That’s what happened to me.

I’m a pediatrician with Westchester Health Pediatrics and the mother of identical twins, Lucas and Zachary. In fact, I myself am an identical twin, too. For an identical twin to have identical twins is very rare, but in my case, it happened!

At first, we were told our twins were fraternal

Deborah V. Tesler, MD, FAAP

When my husband and I found out I was pregnant with twins, we were told at my 5-week ultrasound that they were diamniotic, dichorionic (fraternal) twins, meaning that each embryo had its own chorionic (the outer fetal membrane that encloses the developing embryo) and amniotic sacs.

This occurs most commonly with dizygotic twins (when two separate eggs are fertilized by two separate sperm), resulting in two separate zygotes (fertilized egg cells) with different genetic material. However, it can also occur rarely with a monozygotic pregnancy (the division of a single zygote following fertilization, resulting in both fetuses sharing the same genetic material).

They looked so alike

Turns out, our boys were not fraternal but identical. When they were born, they looked so much alike that the nurses and my family had difficulty telling them apart, so we painted the nails of one twin so we could tell who was who!

Finally, we had them tested and voilà! Identical. My sister and I also got tested and found out that we, too, are identical, after suspecting this but not really knowing for certain.

Through the years, I’ve learned that this happens more often than you’d think. Many twins who are told they are fraternal are actually identical, and go through life not knowing. In my practice with Westchester Health Pediatrics, I’ve had  a few of these cases — twins who were tested and found out they were identical. The reaction each time has been “wow!”

As a twin myself, it was still a shock to find out I was having twins

Once I found out, I felt more prepared in a way, since I understood the bond these babies would have, being a twin myself. I felt this was such a gift for them, and for me.

Nevertheless, I was not as well prepared for the sleepless nights and constant ruckus, with an older child at home as well. (I’ve written a blog about this, What to Know About Raising Twins.) But watching them roll around as toddlers like two teddy bears, and then grow, along with their older brother, into dear young adult friends, there really is nothing more amazing. I feel truly blessed.

Twins bring a higher incidence of high-risk pregnancy, plus other issues

As pediatricians, we are prepared to manage the complex issues that accompany premature delivery of singletons and multiples. According to the University of Rochester Medical Center, some of the more common complications of a multiple pregnancy include:

1. Preterm labor and birth

More than 3 in 5 twins are premature (born before 37 weeks of pregnancy). These newborns are often born before their bodies are fully matured and can be small, with low birth weights. They may need help breathing, eating, fighting infection and staying warm. Some may need to spend a period of time in a neonatal intensive care unit (NICU) until they are ready to come home.

2. Gestational high blood pressure

Women carrying multiple fetuses are more than twice as likely to develop high blood pressure during pregnancy. This can also raise the chance of early detachment of the placenta (placental abruption).

3. Gestational diabetes and anemia

Women with multiple fetuses are more likely to develop gestational diabetes and anemia.

4. Twin-to-twin transfusion syndrome

Twin-to-twin transfusion syndrome is a condition of the placenta that develops only with identical twins who share a placenta (monochorionic twins). This occurs when blood vessels connect within the placenta and divert blood from one fetus to the other. Over time, one fetus gets too much blood and one not enough blood. This condition can be treated during pregnancy.

5. Caesarean (C-section) delivery

Abnormal fetal positions raise the chances of a C-section for pregnancies with twins, triplets and quads.

At any age, count on us for all kinds of information to help you raise healthy and happy kids.

You’ve got questions, we’ve got answers. Whether you’re raising teenagers, adolescents, toddlers or newborns, we’ve got years of experience helping parents take care of their children and we’re ready to help you with yours. Please come in and see us.

Want more information about twins? Come see us.

If you’d like advice and guidance on raising twins, or a single baby, or if you have questions about any aspects of your child’s health and well-being, please make an appointment to come in to see one of our Westchester Health Pediatrics pediatricians. We’ll talk with you, share our tips and advice, and take all the time you need to answer all of your questions. Whenever, wherever you need us, we’re here for you.

To learn more about twins, I recommend these helpful articles:

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By Deborah V. Tesler, MD, FAAP, an identical twin and mother of identical twin boys, Pediatric Physician with Westchester Health Pediatrics, member of Northwell Health Physician Partners

by WHA-Admin