Basic principles of twins
Twins are two or more babies born in the same pregnancy. According to modern medical research, there are two main basic principles for the occurrence of twins: identical twins and fraternal twins. Identical twins are one fertilized egg that splits into two and develops into two identical fetuses. The incidence of this condition is 1 in 3 births worldwide. Fraternal twins are two fertilized eggs that implant in the uterus at the same time and develop into two fetuses independently. The incidence of this condition is higher than that of identical twins, accounting for about 1% to 2% of all fetuses. The occurrence of twins is affected by many factors such as genetic factors, maternal age and gestational age.
Genetic factors for the occurrence of twins
The occurrence of twins is closely related to genetic factors. Identical twins are more likely to have twins if one of their relatives already has identical twins. For fraternal twins, if the mother is a twin, she has a higher chance of giving birth to twins herself. In addition, some syndromes, such as Schindler syndrome and Edwards syndrome, also increase the chance of having twins.
Maternal age and gestational age factors in the birth of twins
Maternal age affects the incidence of twins. Older women have a higher chance of giving birth to twins. In addition, gestational age is also a factor in the occurrence of twins. According to research, pregnant women with a gestational age of 35 weeks and above have a higher chance of giving birth to twins. This is because the uterine wall is already loose and the embryos can easily divide and form twins.
Physical characteristics and personality differences between twins
Even identical twins can have differences in their physical characteristics and personalities. The physical characteristics of twins are often similar in appearance, but their bodies, peanut sizes, and growth and development are different. In addition, twins have quite different personalities, including lifestyles, social hobbies, etc.
Conclusion:
Generally speaking, there are many reasons for twins, affecting many aspects, such as genetic factors, maternal age and gestational age. Although the appearance of twins is due to some basic principles, the differences are very large. Therefore, there are still great individual differences between different twins.
