Twins are at increased risk of fetal and infant death compared with singleton births. 1-3 The increased risk is partly the result of the lower birthweight and gestational age at delivery of multiple pregnancies. At particular risk are monozygotic twins who have poorer survival rates than dizygotic twins.
Monochorionic-diamniotic twins are identical twins that share a placenta but each develops in their own separate amniotic sac. This is the most common type. Monochorionic-monoamniotic twins are identical twins that share both a placenta and an amniotic sac. This is the rarest and highest risk form of twin pregnancies.
Monochorionic twins have the highest risk of congenital malformations, perinatal mortality and morbidity. The incidence of monochorionic twins is very low, the outcomes for this kind of twins and the best gestational age for delivery have not been well studied.
A pregnancy with fraternal twins has the lowest risk of all multiple pregnancies. This is because each baby has its own placenta and amniotic sac. You will sometimes hear fraternal twins referred to as 'dizygotic' twins. This refers to 2 zygotes (fertilised eggs).
Twins are also more prone to birth asphyxia, hyaline membrane disease, respiratory disorders, and seizures. Congenital anomalies and nonrespiratory morbidity were not found to be increased in twins. Twins have a six times higher perinatal mortality rate than do singletons.
Overall, the infant mortality rate for all multiple births (twins, triplets and higher multiple births) was five times higher than for single births (20.4 deaths per 1,000 live births compared with 4.0 deaths per 1,000 live births). However, most deaths among multiples occurred during the first 28 days of life.
The mean of gestational age for twins, triplets and quadruplets were 33.92 ± 3.5 weeks, 30.92 ± 3.8 weeks and 31.60 ± 2.0 weeks, respectively, (P = 0.0001). Triplets and quadruplets weighed less than twins, (P = 0.0001). Neonatal mortality was 13.5% for twins, 26.8% for triplets and 30% for quadruplets.
About twins
The main types of twins are fraternal twins and identical twins. Most twins are born healthy, but a twin pregnancy can mean a higher chance of health complications for you and your babies. If you're pregnant with twins, you and your babies will need extra check-ups.
While there are risks associated with all twin pregnancies, dizygotic (fraternal) twin pregnancies usually bring about the least amount of complications, carrying the lowest risk of all types of twins. Worse complications are possible with monozygotic (identical) twins because the embryo is dividing.
Being pregnant with multiples doesn't necessarily mean that your pregnancy will be problematic. However, women carrying multiples do have a higher chance of developing complications such as high blood pressure and preterm labor. For this reason, all multiple pregnancies are considered high-risk.
Dizygotic twins are the most common type and are known as fraternal twins. Two-thirds of all sets of twins are dizygotic. When two eggs are fertilized during the same pregnancy, the result is a set of dizygotic twins. They are fertilized by two different sperm.
Twin development at 24 weeks
Your twins are becoming more developed to be ready for life outside of the womb. At 24 weeks, they are considered viable and could possibly survive outside of the womb - in an intensive care unit, with a lot of help. However, they still have quite some developing to do and weight to gain.
In 2020, the fetal mortality rate was highest for non-Hispanic Native Hawaiian or Other Pacific Islander (10.59) and non-Hispanic Black (10.34) women and lowest for non-Hispanic Asian women (3.93).
If you're 30 or older, you're more likely than younger people to release more than one egg during a menstrual cycle. You have relatives who have had multiples. If you or other people in your family have had fraternal twins, you may be more likely to have twins, too.
In fact, one British study tested ESP potential among identical twins and found that they were correct about 25% of the time, the same as any other siblings. There is one particular power though which twins possess, longevity. Fraternal twins live longer than singletons and identical twins longer still.
Identical twins are less common than fraternal twins. Identical twins happen in about 3 to 5 out of every 1,000 births. While fraternal twins tend to run in families, identical twins don't.
The chance of a twin miscarriage that affects both babies is around 5 to 10 percent, says Robin Kalish, MD, FACOG, a specialist in high-risk pregnancies.
The quick answer to this question is that, in a twin pregnancy, it is the mother's genes that determine twins. First up, giving birth to identical twins is not genetic, but conceiving fraternal twins is. The mother may have the genetic trait of releasing two eggs in one menstrual cycle.
Early loss (miscarriage) of a twin or multiple
Vanishing twin syndrome most often occurs in the first trimester, sometimes before a woman even knows she's carrying twins.
A twin pregnancy requires more frequent prenatal visits because there are higher chances of complications. Most people who are pregnant with twins deliver just before they're considered full-term. Though twins are often born via c-section, talk to your provider about the possibility of a vaginal delivery.
The birth process is similar to giving birth to a single baby. If you're planning a vaginal birth, your health team may recommend that you have an epidural for pain relief.
Some of the causes of intrauterine death in twins are genetic factors, congenital defects or a wide range of placental abnormalities,” says Sonmez. If a twin dies early on in the pregnancy in the first trimester, it can often be without the mother or doctor knowing.
Barring pregnancies that result from assisted reproductive technology, dizygotic twins are far more common than monozygotic twins and account for 70 percent of all twin gestations.
If the twin dies in the second or third trimester, there are increased risks to the surviving fetus, including a higher rate of cerebral palsy. When a twin dies after the embryonic period of gestation, the water within the twin's tissues, the amniotic fluid, and the placental tissue may be reabsorbed.
The major complications that account for nearly 75% of all maternal deaths are (2): severe bleeding (mostly bleeding after childbirth); infections (usually after childbirth); high blood pressure during pregnancy (pre-eclampsia and eclampsia);