What Are My Odds and Chances of Having Twins?

Statistics about twins, triplets, and multiple births

Couple on bed with twin babies.
Getty Images / Jade Brookbank

What are the chances of having twins? Odds are, if you're already a parent of multiples, you may find yourself marveling at your unusual family dynamics and think "Why did this happen to me? How did I get so lucky?" (or unlucky, depending on the moment!)

If you're not yet a parent of multiples, you might wonder what it takes to become one. Are you a candidate for twins, triplets, or more?

The odds of having multiples are influenced by many factors, both personal and at the population level. Twinning rates have changed throughout the years because of these changing influences.

It can be interesting to analyze the statistics and contemplate your personal odds for winning the multiples lottery. However, keep in mind is that these statistics (the odds or chances of having twins or multiples) are based on populations, not individuals.

It is not possible to quantify a specific number for a person—for example, saying that their particular chance of having twins is 1 in 100. Rather, curious parents can consider the statistics for entire populations in relation to the factors that increase or decrease the chances of having twins.

General Statistics About Twins and Multiples

Within the general population in the 21st century, the chances of having twins are about 3 in 100 (about 3%). That said, your chances are better than ever (or at least, better than previous generations).

Researchers have recorded an increase of nearly 60% since the early 1980s. The most recent statistics, published as part of a 2017 study by the National Center for Health Statistics, show that twins represented 33.3 of every 1,000 births.

You'll increase your odds of having twins/multiples if:

  • You take fertility drugs or other fertility treatments. Research appears to show that fertility enhancements have contributed to increased multiple birth rates, but no study has been able to conclusively pinpoint the impact of these treatments. Researchers estimate that the chances of having twins after fertility-enhancing treatment are as high as 1 in 38. Other estimates show a 6% chance of twin births in couples using the drug Clomid.
  • You, your mother, or her mother's mother is a fraternal twin. Women who are multiples themselves might carry a gene for hyperovulation (meaning that they release more than one egg during an ovulation cycle). Hyperovulation increases the ability to conceive fraternal twins. The chances of twins might be as high as 1 in 17 if the mother is a fraternal twin.
  • You live in Michigan or Connecticut. A 2018 study found that these two states had the highest twin birth rates in the U.S. — 35.9 and 36.4 per 1,000 births, respectively.
  • You're Nigerian. This African country purportedly has the highest twinning rate in the world—an estimated 19 per 1,000 births. Some sources have attributed to the consumption of large quantities of yams.
  • You (the mother) are over age 45. Research has shown that the chance of having twins increases with age. In a study of pregnant women over the age of 45, 16% had multiple pregnancies, with twins being the most common outcome. Becoming a mother after the age of 50 boosts your odds of twins considerably.
  • You (the mother) are overweight or tall. A study published in 2010 reported a significant increase in fraternal twin births to mothers who had a BMI of 30 or higher, or who were in the top 25th percentile for height.

You'll decrease your odds of having twins/multiples if:

  • You (the mother) are Hispanic or Asian. The study by the National Center for Health Statistics found that women of Hispanic origin were substantially less likely to have twins than white or black mothers. Worldwide, China and Thailand have the lowest twinning rates, estimated at 7.9 and 6.8 per 1,000 births, respectively.
  • You're relying on the chances of identical multiples. The rate for identical (monozygotic) multiples is random and universal. This means the chances are the same in all populations regardless of race, heredity, or other factors. The rate of having identical twins has remained constant over time and is about 3 to 4 per 1,000 births.
  • You (the mother) are younger than 25. The chances a woman will have twins before her 25th birthday are less than half of what they would be at the age of 35.

Odds of Triplets/Quadruplets/Higher Order Multiples

The statistics for higher-order multiples have shown a dramatic increase in recent years. The odds of conceiving "spontaneous" triplets (i.e., without the aid of fertility enhancements) are about 1 in 4,000.

Researchers have noted a substantial increase in the rate of triplet births over the last twenty years. It is estimated that around 77% of triplets are the result of fertility-enhancing treatments.

The odds of having spontaneous quadruplets are even higher—predicted to be 1 in 729,000.

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  1. Sahu M, Prasuna JG. Twin studies: A unique epidemiological toolIndian J Community Med. 2016;41(3):177–182. doi:10.4103/0970-0218.183593

  2. U.S. Department of Health and Human Services. Centers for Disease Control and Prevention. National Center for Health Statistics. National Vital Statistics Reports. Births: Final data for 2017. Updated November 2018.

  3. Jones CA, Christensen AL, Salihu H, et al. Prediction of individual probabilities of livebirth and multiple birth events following in vitro fertilization (IVF): A new outcomes counselling tool for IVF providers and patients using HFEA metricsJ Exp Clin Assist Reprod. 2011;8:3. PMID:21991292

  4. Schram CA. Outdated approach to a common problemCan Fam Physician. 2016;62(9):713–716. PMID: 27629665

  5. National Institute of Health. U.S. National Library of Medicine. Genetics Home Reference. Is the probability of having twins determined by genetics?. Updated May 2020.

  6. U.S. Department of Health and Human Service. Centers for Disease Control and Prevention. National Center for Health Statistics. Is twin childbearing on the decline? Twin births in the United States, 2014-2018. Updated October 2019.

  7. Smits J, Monden C. Twinning across the developing worldPLoS One. 2011;6(9):e25239. doi:10.1371/journal.pone.0025239

  8. Rendtorff R, Hinkson L, Kiver V, Dröge LA, Henrich W. Pregnancies in women aged 45 Years and Older - A 10-Year retrospective analysis in BerlinGeburtshilfe Frauenheilkd. 2017;77(3):268‐275. doi:10.1055/s-0043-100105

  9. Reddy UM, Branum AM, Klebanoff MA. Relationship of maternal body mass index and height to twinning. Obstet Gynecol. 2005;105(3):593-7. doi:10.1097/01.AOG.0000153491.09525.dd

  10. Rodgers JL, Bard DE, Miller WB. Multivariate Cholesky models of human female fertility patterns in the NLSYBehav Genet. 2007;37(2):345–361. doi:10.1007/s10519-006-9137-9

  11. Fell DB, Joseph K. Temporal trends in the frequency of twins and higher-order multiple births in Canada and the United StatesBMC Pregnancy Childbirth. 2012;12:103. doi:10.1186/1471-2393-12-103

  12. Avraham S, Seidman DS. The multiple birth epidemic: RevisitedJ Obstet Gynaecol India. 2012;62(4):386‐390. doi:10.1007/s13224-012-0309-7

  13. Kulkarni AD, Jamieson DJ, Jones HW Jr, et al. Fertility treatments and multiple births in the United StatesN Engl J Med. 2013;369(23):2218‐2225. doi:10.1056/NEJMoa1301467

  14. Carrara S, Cavaliere A, Ermito S, Dinatale A, Pappalardo EM, Militello M. Case report: Successful of a spontaneous quadruplet pregnancyJ Prenat Med. 2009;3(1):10–11.