Understanding the Three Stages of Twin Pregnancy

Contributors: Carolina Bibbo, MD, is a maternal-fetal medicine (MFM) specialist and director of the Comprehensive Care Center for Multiples at Brigham and Women's Hospital. Lucy Graves, MSN, RN, CBS, is a nurse in the center.

Every pregnancy is special, but being pregnant with twins, triplets or more is different. In order to prepare you for what lies ahead, Dr. Carolina Bibbo and Lucy Graves offer insight into the three stages, or trimesters, of a twin pregnancy.

First Trimester: Is Everything Okay?

For someone expecting twins, the first clinic visit typically occurs between weeks 8 and 10 of the pregnancy. At this visit, a nurse in the Comprehensive Care Center for Multiples:

  • Reviews your medical history and other personal information
  • Provides details about twin pregnancy and our practice
  • Answers your questions and offers tips to ease symptoms like nausea and vomiting

This process takes about an hour and is done over the phone.

At 11 to 13 weeks, you can expect to meet your MFM provider. "At this visit," Dr. Bibbo says, "most families are anxious to hear that everything is okay with their babies." You also have a nuchal translucency ultrasound, which checks for fluid collection at the back of each baby's neck. This is a way to check for a potential genetic problem early on, but there is another benefit: The babies are pretty big by now, and their heads, arms and legs can be clearly viewed.

"Most patients are in awe that they can see so much detail about their little ones," Dr. Bibbo says. "The pregnancy now feels real."

During this same period, you have the option to meet with a genetic counselor virtually to discuss further tests. At the Center for Multiples, our patients appreciate the detailed information that our genetic counselors provide. Our experienced clinicians at the Brigham's Center for Fetal Medicine and Prenatal Genetics can perform diagnostic testing such as chorionic villus sampling and amniocentesis should these procedures be required.

In the Center for Multiples, you also have the opportunity to meet virtually with one of our nutritionists to talk about your nutritional and weight-gain goals and concerns.

Second Trimester: Babies' Growth

As nausea and vomiting usually resolve by the second trimester, you can expect your appetite to return. The focus shifts to making sure your babies receive the nutrients they need to grow. Many patients carrying twins find this trimester to be the most enjoyable.

Your babies' anatomic survey is done between 18 and 20 weeks. This ultrasound provides details about the anatomy of your babies and includes views of their brains, hearts and kidneys. Sometimes this ultrasound is repeated a few weeks later if these organs were not clearly seen due to the position of the babies. This test can take an hour, but most families enjoy the experience. "What's nice about this ultrasound is that you often leave with images of your babies' faces, hands and feet," Graves says.

Very occasionally, the anatomic survey reveals that there might be a problem with one of your babies. One example is a heart defect, like a small hole in the heart.

"A wonderful thing is that we work very closely with Boston Children's Hospital," Dr. Bibbo says. "If we recognize there is a problem with one of the babies that potentially requires surgery following birth, we can easily schedule an appointment with a specialist there while the mother is still pregnant. That visit typically includes additional imaging, such as an echocardiogram [an ultrasound of the heart] to get a closer look, and a meeting with the team that will care for the baby once born."

We also offer the option to meet with one of our genetic counselors to decide whether to pursue further testing that would reveal if the problem is genetic in nature.

Around 24 to 28 weeks, you undergo screening for anemia (lack of healthy red blood cells) and gestational diabetes (a form of high blood sugar). Both of these conditions are more common in multiple pregnancies.

By late in the second trimester, the "bump" in your stomach is quite noticeable. You start to feel your babies kick. Suddenly, the delivery doesn't seem very far off.

Third Trimester: Getting Ready for the Delivery

During the third trimester, your visits become more frequent so your care team can carefully monitor the health of you and your babies. At the last few visits, the team:

  • Reviews labor and delivery in greater depth
  • Works with you to determine the best mode of delivery (we encourage vaginal delivery when possible)
  • Discusses what to expect in the postpartum period (the first 6 to 12 weeks after birth)
  • Helps you make sure you are prepared for life at home with the newborns

With a twin pregnancy, your babies are more likely to be born early. That means one or both may require specialized intensive care after birth. The Brigham's Newborn Intensive Care Unit (NICU) is one of the largest and most advanced in New England and was designed with twins in mind. If you have any concerns about the possibility of newborn intensive care, we can arrange for a virtual tour of the facility and a meeting with a member of the NICU team.

At the Brigham in the third trimester, you can sign up for childbirth, breastfeeding and other classes designed especially for families expecting multiples. In addition, Dr. Bibbo and Graves co-host monthly Q&A sessions open only to multiple families. These one-hour gatherings, held virtually, cover topics such as delivery, preparing your home for your babies and postpartum check-ins. The Center for Multiples' social worker is also available to support you from early in your pregnancy through postpartum.

"The medical care here is excellent, as it is in most hospitals in the area," Dr. Bibbo says, "But all the other things we offer — the social and emotional support, the specialized classes, the Q&As — are what really set the Brigham's Center for Multiples apart from other programs."

Learn more about the Comprehensive Care Center for Multiples.

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We understand that you may have concerns and want to assure you that we are steadfast in our commitment to safely providing the care you need. Our experts in the Comprehensive Care Center for Multiples are available to connect with you in person and with Virtual Visits. To request an appointment, call 617-732-5130 or submit the form below.

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