Reports from various domestic media outlets on April 22nd reveal that a woman with infertility in Shandong Province has been found to be pregnant with triplets, with both identical and fraternal twins occurring simultaneously.
The doctor commented, "This is the first time I've encountered such a situation."
Data indicates that twins can be categorized into two types: identical twins and fraternal twins.
Identical twins, also known as monozygotic twins, originate from a single fertilized egg that splits into two embryos. Because they come from the same fertilized egg, they share identical chromosomes and genetic material, resulting in the same gender and striking physical resemblance, sometimes making it difficult for even their own parents to distinguish between them.
Fraternal twins, on the other hand, develop from two separate fertilized eggs, each having its own placenta, with no biological connection between them. Physically, they resemble ordinary siblings. For instance, most cases of mixed-gender twins are fraternal twins, rather than identical twins.
As for triplets, in natural circumstances, the occurrence of triplets, quadruplets, or higher-order multiples is relatively rare and typically happens with the assistance of reproductive technologies.
