About 770-900 twin pairs are born each year in Finland. Twins are divided into identical and non-identical twins. Multiple pregnancies are always risk pregnancies with a higher frequency of follow-up at the maternity clinic.
Twins account for 1.4 percent of all births. About half of twins are born full-term (≥ 37 weeks gestation) and half are premature before 37 weeks of gestation. The majority of preterm (40%) children are born prematurely at 32-36 weeks of gestation.
Division of twin pregnancies: Twins are divided into identical, that is, identical eggs, and non-identical, that is, different eggs. Identity is determined by the genome. During pregnancy monitoring, twin pregnancies are divided according to the so-called body bond, which is determined by whether the fetus has a common placenta or separate placenta. In most cases, the crosstalk can be determined by the first ultrasound screening.
Fetuses have their own placenta: Dicorial Diaminal (DI), that is, both fetuses have their own veins and membranes. This is the most common form of twin pregnancy, 70-80 percent of all twin pregnancies. 90% of these are twin eggs, meaning that the children are non-identical, whereby two ova are fertilized by two different sperm. About 10 percent of all DI twins are identical, due to the distribution of fertilized ova at the very beginning of pregnancy. When the distribution occurs within 1-3 days after fertilization, two separate placentae are formed. The identity of the children can be verified after birth.
Fetuses have a common placenta: If the placenta is common, the children born are so-called. identical twins from the same fertilized egg. One fertilized egg divides into two embryos within the first days. Generally, distribution occurs before attachment to the uterine wall. So the children have the same genome.
Monocorial, diaminal (MO-DI), that is, fetuses have a common choroid membrane but both have their own membranes. This is the second most common form of twin pregnancy, 20-30 percent of all twin pregnancies.
Monocorial-Mono-Amniotic (MO-MO); both fetuses are within the same choroidal and aqueous membranes.
Follow-up during pregnancy: Multiple pregnancy is always a risk pregnancy. The clinic and maternity clinic follow these pregnancies together. Twin pregnancies carry a multiple risk of premature birth and low birth weight. The risk of fetal death has also increased. The risks are higher in monocortical twin pregnancies. In fact, the frequency of follow-up in maternity clinics is higher in these pregnancies. Routine hospitalization or medication is not helpful in preventing premature death.
Monocortical twin pregnancy (MO-DI and MO-MO): After the first ultrasound screening, the maternity ward is monitored every 2 weeks by a specialist. Fetal well-being is monitored for growth, movement and amniotic fluid. These are used to identify references to the so-called. Feto-fetal transfusion. The actual structure examination is done during weeks 20-21 of pregnancy, but the structure is reviewed at each follow-up visit. Medical visits occur every two to three weeks during pregnancy. At each visit to the doctor, the cervical condition and fetal growth are evaluated. The date of the next visit will be decided on the basis of these studies. There is no need for a routine visit to the GP because the physician in the maternity clinic is monitoring pregnancy. Instead, visits by a nurse to a clinic are important.
Dicorial n Twin Weight (DI): The first and second so-called. The structure of the ultrasound screening is done by a midwife. You will receive a first appointment at the maternity ward for pregnancy from 23 to 24 weeks of pregnancy, unless previously found to be abnormal. Medical appointments are every four weeks for the first time and every two weeks for the final pregnancy. At each visit to the doctor, the cervical condition and fetal growth are evaluated. The date of the next visit will be decided on the basis of these studies. There is no need for a routine visit to the GP because the physician in the maternity clinic is monitoring pregnancy. Instead, visits by a nurse to a clinic are important.
Exercise and outdoor activities are possible and desirable during pregnancy, as in single pregnancy, but towards the end of pregnancy, other heavy physical activity should be reduced.