Hello Good Evening, Human multiple births can occur either naturally (the woman ovulates multiple eggs or the fertilized egg splits into two) or as the result of infertility treatments such as IVF or fertility drugs. For reasons that are not yet known, the older a woman is, the more likely she is to have a multiple birth naturally. It is theorized that this is due to the higher level of follicle-stimulating hormone that older women sometimes have as their ovaries respond more slowly to FSH stimulation. If you experience any of following to an unusually extreme degree, it may be a sign that you are carrying multiples. Weight gain: A singleton mother gains, on average, five to seven pounds in the first trimester. Anything more could indicate multiples…or excessive junk food consumption! Abdomen size: With multiple babies in her womb, a pregnant woman tends to outgrow her regular clothing and require maternity gear sooner. Fatigue: Excessive fatigue is one of the most commonly reported complaints of mothers of multiples in the early stages of pregnancy. Fetal movement: It s very unusual for a mother to experience fetal movement in the first trimester, yet there is some evidence to suggest that the sensation is more acute when there is more than one baby moving around. Nausea: Extra babies can intensify the symptoms of morning sickness, such as nausea and vomiting. So go for a USG and find definite results. Regards, Dr. Naresh Jain.