Learning you are expecting twins, triplets or higher-order multiples can be exciting but also overwhelming. A multiple pregnancy is different than a singleton pregnancy in a variety of ways.
Families at the Brigham's Comprehensive Care Center for Multiples often have questions about keeping mom and babies healthy, possible complications during pregnancy and delivery, what additional testing is needed and much more. Our experts are here with answers to keep you well-informed throughout your pregnancy.
Both Doctor and Nurses are always so informative and a pleasure to speak to. I know I’m not the only patient, but they sure make me feel special to be carrying twins. They ease my nerves. They always make me feel comfortable and joyful when I leave my appointment. I cannot wait for them to deliver my two healthy baby boys.” - Tania, patient
Our highly experienced team in the Comprehensive Care Center for Multiples offers the full range of specialized prenatal care for a multiple pregnancy. Watch the above video to learn more.
Any woman carrying more than one baby should receive routine aneuploidy screening. This assessment reveals whether a fetus is at higher risk of having an abnormal number of chromosomes — as in the case of Down syndrome.
Because you are carrying more than one baby, genetic screening options and interpretation of the results are slightly different and require medical expertise. Every patient at the Center for Multiples meets with a genetic counselor who specializes in multiple gestations. After meeting with one of our genetic counselors, you will have all the information needed to proceed with the best genetic screening options or diagnostic tests for your multiple pregnancy.
We employ common diagnostic tests such as:
When you have a twin pregnancy, your prenatal care (prenatal visits and ultrasound) will be based in part on the type of twins you are carrying. In general, this refers to whether the twins each have their own placenta, share one placenta or share one placenta and one amniotic sac.
Fraternal (dizygotic) twins are conceived when two separate eggs are fertilized and implanted in the uterus at the same time. The twins have different genetic makeups and may or may not be the same gender. All fraternal twins are dichorionic-diamniotic (Di-Di) twins.
Identical (monozygotic) twins are conceived when one egg becomes fertilized and then splits into two separate embryos. They are the same gender and have the same or nearly the same genetic makeup. They may not be exactly identical because some genes are expressed differently.
Monozygotic twins are classified as follows:
Triplets are classified as follows:
In rare cases, two of the triplets can also share the placenta and amniotic sac.
Triplet pregnancies are at a higher risk of complications related to preterm birth. On average, triplets are delivered around 32 weeks. A consultation with a maternal-fetal medicine (MFM) specialist is recommended to review potential risks and pregnancy outcomes.
During a multiple pregnancy, more frequent ultrasounds are necessary to monitor the babies' growth rates and any possible complications.
Below are our general guidelines for ultrasounds during a multiple pregnancy. Please keep in mind that the schedule may differ depending on your particular circumstances.
|
Purpose of Ultrasound |
Timing |
Additional Notes |
|
Determining date of pregnancy and type of twins or triplets |
Optimal at 7–10 weeks |
Measure twins or triplets (often referred to as the "crown-rump length"). |
|
Conducting aneuploidy screening |
10–13 weeks |
Assess each baby's nuchal translucency measurement and early anatomic structures. (Nuchal translucency screening uses an ultrasound test to check the area at the back of the fetal neck for extra fluid.) |
|
Scanning anatomy for all multiples |
Optimal at 18–20 weeks |
Assess for structural abnormalities. |
|
Follow-up for uncomplicated Di-Di twins |
Starting at week 24 |
Assess fetal growth every 4 weeks. |
|
Follow-up for uncomplicated Mo-Di and Mo-Mo twins* |
Starting at week 16 |
Assess:
|
|
Follow-up for uncomplicated Tri-Tri triplets |
Starting at week 24 |
Assess for fetal growth every 2–4 weeks |
* Uncomplicated Mo-Mo twins follow a similar ultrasound schedule as uncomplicated Mo-Di twins until admission to the hospital for inpatient daily fetal testing around 24–28 weeks.
The Center for Multiples is part of the Division of Maternal-Fetal Medicine, which offers the most advanced maternity care available today. Care is provided by MFM specialists, who bring expertise in managing the challenges and complications of high-risk pregnancies. Please note that not all twin pregnancies are considered high-risk pregnancies.
If you develop medical complications related to your health or the health of your babies, a consultation with a MFM specialist may be recommended. If you receive your prenatal care at a practice outside of the Brigham, you can have a consultation with one of our MFM specialists and retain your local obstetrician.”
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