Though quintuplets and other higher-order multiple births (also known as super twins) are rare, the increased use of fertility drugs and assisted reproduction techniques has also brought an increase in these types of pregnancies. Here’s all you need to know about quintuplets.

Types of Quintuplets

Quintuplets can be fraternal (polyzygotic), identical (monozygotic), or a combination of both. Polyzygotic quintuplets occur from five unique egg/sperm combinations whereas monozygotic multiples are the result of one fertilized egg that splits into two or more embryos. It is possible for a split to occur more than once, producing ​monozygotic triplets or even a rare set of monozygotic quintuplets. Fully monozygotic quintuplets are rare—so unusual, in fact, that it is difficult to even assess the odds of their occurrence. Quintuplets can be all male, all female, or a combination of both, but monozygotic quintuplets will always be of the same sex because they come from the same fertilized egg.

Odds of Quintuplets

Quintuplet pregnancies are very rare. In 2017, the National Vital Statistics Report showed the birth of 49 quintuplets and higher-order multiples. Because this number includes the possible birth of sextuplets, septuplets, or more, it is not certain exactly how many of those births were specifically quintuplets. The spontaneous conception of quintuplets is extremely rare; the average estimate is 1 in over 60 million births. Most recent quintuplet births are the result of assisted reproductive techniques such as fertility-enhancing drugs or in vitro fertilization (IVF).

Pregnancy and Birth With Quintuplets

The average gestation for a quintuplet pregnancy is 29 weeks. This is 11 weeks shorter than the 40 weeks for a full-term baby. Many people pregnant with multiples will gain more than 50 pounds during their pregnancy and may have to undergo a cervical cerclage, a surgical procedure in which the cervix is sewn shut to prevent preterm labor. However, research is mixed on the efficacy of this intervention. That said, quintuplets don’t always share the same birthdate. A delayed interval delivery (also known as iatrogenic asynchronous birth) may mean that individual babies are born days or even weeks apart.

The First Quintuplets

Perhaps the most famous set of quintuplets are the Dionne quintuplets born in Canada in 1934. They were the first documented set of all identical quintuplets to survive infancy. The girls—Annette, Émilie, Yvonne, Cécile, and Marie—attracted worldwide attention. Unfortunately, this fame also brought misfortune. The children were removed from their parent’s care and placed in the custody of a doctor, who displayed them as a tourist attraction.

Support Groups for Families

Are you having quintuplets? While often considered a blessing, having multiples comes with unique parenting and health challenges. It can be helpful for families to seek support and advice from other families in the same situation for community and advice. Here are some organizations that can offer resources and assistance:

Australian Multiple Birth Association (AMBA) [Australia] Multiple Births, Canada’s Higher Order Multiples Support Network [Canada] New Zealand Multiple Birth Association (NZMBA) [New Zealand] Raising Multiples, a MOST (Mothers of Supertwins) community [United States] Twins and Multiple Birth Association (Tamba) [United Kingdom]