Twins or More What Do You Call Four, Five, Six or More Babies? By Robin Elise Weiss, PhD | Reviewed by Anita Sadaty, MD Updated January 16, 2019 Pin Flip Email Print Illustration by Hugo Lin. © Verywell, 2018. More in Pregnancy Twins or More Weeks and Trimesters Your Body Your Baby Staying Healthy Complications & Concerns Pregnancy Loss Prenatal Care Preparing for Baby Labor and Delivery Postpartum Care View All Even though multiple births are rare, the public fascination with them persists. Thanks to reality TV, we've heard of quintuplets (5 babies at once) and sextuplets (6 babies at once) along with other higher-order multiples. Learn the nomenclature and other facts about multiple births. A Simple Chart of Multiple Birth Terms This quick reference can help you know what to call sets of multiples. Number of Babies Term Used 1 Singleton 2 Twins 3 Triplets 4 Quadruplets (quads) 5 Quintuplets (quints) 6 Sextuplets 7 Septuplets 8 Octuplets 9 Nonuplets The prefixes for the numbers four through nine come from Latin for those numbers. Single, twin and triplet come from Middle English. Twins Are More Common Than Triplets or More According to the United States National Vital Statistics Report, there are approximately 33.4 sets of twins born for every 1,000 live births and 101.4 sets of triplets or more per 100,000 births. In other words, twins are a lot more common (about 3 percent of all live births) versus a pregnancy with three or more babies (about 0.1 percent of all live births), sometimes called super twins. Changes in Triplet and High-Order Multiple Births The rate of twin, triplet, and high-order births began to climb in the 1980s, especially among non-Hispanic white women age 25 and over, because of the use of fertility drugs and assisted reproduction techniques. While the rate of twin births increased by over 50 percent, the rate of triplet and higher order multiples increased by over 400 percent. The rate peaked for triplets and higher multiples from 1998 to 2004 and has since been dropping, again in the same demographic group responsible for the rise. This is due to a change in assisted reproduction treatments, especially in the transfer of fewer embryos. The rates are still three times what they were in the early 1980s. This is a concern because the risks of mortality and long-term morbidity continue to be far higher for triplets and higher order multiples than for singletons. How Multiple Births Occur How, exactly, does a woman conceive multiple babies, with or without assisted reproduction treatments? Identical Every month, a woman releases an egg from her ovary (this process is called ovulation), which can then be fertilized by a sperm to form an embryo and, eventually, a developing fetus or baby. If an embryo happens to split into two or more embryos, identical twins (or more) may result. Due to the splitting of the embryo, identical twins share the same DNA. This is why they are always of the same gender. Fraternal On the other hand, some women release more than one egg during ovulation; they "hyperovulate," so to speak. Experts are not quite sure why some women hyperovulate and others do not, but there is believed to be a genetic component to it—a hyperovulation gene. In addition, age plays a role, as women older than age 35 are more likely to release more than one egg during each menstrual cycle. If a woman releases two or more eggs during ovulation, each may be fertilized by a different sperm, forming unique embryos. In this case, twins would be fraternal, not identical; they can be of different genders or the same gender. Similarly, two (or more) embryos may be formed through assisted reproduction techniques, and then transferred to the uterus. Interestingly, sometimes a combination of the above processes occur. For example, a woman could hyperovulate, releasing multiple eggs during the middle of her menstrual cycle. These eggs are each fertilized by a sperm, and then one or more of these embryo splits. In this instance, a woman could have multiple births (such as quadruplets) with two of the babies being fraternal twins and two being identical. Complications of Multiple Pregnancies In a multiple pregnancy vs. a singleton pregnancy, the mother is more at risk of these complications: Preterm birthPreeclampsia Gestational diabetes In addition, postpartum depression and early parenthood mental health problems may be more likely to occur in women who have a multiple pregnancy. A Word From Verywell If you, your partner or a loved one is expecting multiple babies, it's good to gain knowledge. Be sure to talk with your doctor about some of the more difficult topics associated with multiple birth, like the maternal and fetal risks of a multiple pregnancy. Was this page helpful? Thanks for your feedback! Get diet and wellness tips to help your kids stay healthy and happy. Email Address Sign Up There was an error. Please try again. Thank you, , for signing up. What are your concerns? Other Inaccurate Hard to Understand Submit Article Sources American College of Obstetricians and Gynecologists. Multiple Pregnancy. FAQ188, July 2015. Martin JA, Osterman MJK, Thoma ME. Declines in Triplet and Higher-order Multiple Births in the United States, 1998–2014. NCHS Data Brief No. 243, April 2016. Multiple Births. Centers for Disease Control and Prevention. Wenze SJ, Battle CL, Tezanos KM. Raising Multiples: Mental Health of Mothers and Fathers in Early Parenthood. Archives of Women’s Mental Health. 2015;18(2):163-176. Continue Reading Article What Do You Know About Dizygotic Twins? 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