The duration of a baby’s pregnancy is 40 weeks, although from week 37 to week 42 counting from the date of the last menstruation, it is considered a full-term baby.
We are talking about the average duration of an individual pregnancy, but what about a multiple delivery of more than one baby? We know that when two or more babies come, the duration of pregnancy shortens, but in what average week are twins or twins, triplets or quadruplets usually born?
According to the American Pregnancy Association, single pregnancies have an average duration of 39 weeks, double pregnancies 36 weeks, in the case of triplets 32 weeks, quadruplets 30 weeks, and quintuplets 29 weeks.
Twin pregnancies
Twin pregnancies, either twins (bizygotic twins) or twins (monozygotic twins), are considered high-risk pregnancies, as they increase the risk of having preterm birth and needing a cesarean section. However, a twin pregnancy does not by itself mean having a cesarean delivery . A vaginal delivery can be attempted if medical conditions permit.
Regarding the best week for the birth of twins, a large international study published in the British Medical Journal in 2016 points out that bringing the twins early to the 37th week of gestation minimizes the risks of intrauterine and neonatal death, the one that occurs in the first 28 days after birth.
More babies, more prematurity
Births of more than one baby almost always occur prematurely. Most of the time, preterm labor is triggered by the premature rupture of membranes before the onset of labor in a pregnant woman who is less than 37 weeks gestation.
Almost 60 percent of twins are born prematurely, while 90 percent of triplets are premature.
Delayed intrauterine growth
In multiple pregnancies, babies grow at the same rate as in single pregnancies up to a point, after which growth begins to slow .
This is known as delayed intrauterine growth, which occurs most often from placental causes, when the placenta cannot handle more growth and babies are “competing” for nutrients.
The growth rate of twin pregnancies begins to slow at around 30 to 32 weeks, in triplet pregnancies it begins to slow down at 27 to 28 weeks , and in quadruplet pregnancies it begins to slow down at 25 or 26 weeks.
In Babies and more | Twin delivery: what you should know about multiple births
