how are twins
Doctors do not fully understand why twins occur. However, some factors are believed to be responsible for this such as the age of the woman, history of having twins in the family and fertility treatment.
Pregnancy occurs when the sperm reaches the fertilized egg to form an embryo. However, if two eggs are present in the uterus at the time of fertilization or the fertilized egg splits into two embryos, the woman can become pregnant with twins.
Also read: To have twins, increase your fertility in these ways
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