Chances of having a twin pregnancy are increased by maternal age (30+). Fraternal twinning is genetically predisposed and the result of a woman releasing more than one egg at the same time. Identical twins are the result of a random split of a single egg and cannot be genetically predisposed. Male twins will not have twins unless their wives have the ability to produce two eggs.
Identical twins share the same DNA but do not have the same fingerprints. 1 in 250 pregnancies can result in identical twins. 22 % percent of twins are left-handed compared to 10% in singletons. Vᴀɴɪsʜɪɴɢ ᴛᴡɪɴ sʏɴᴅʀᴏᴍᴇ- 15-20% percent of all twin pregnancies will ᴍɪsᴄᴀʀʀʏ ᴏɴᴇ ғᴇᴛᴜs.
Once you have fraternal twins you are 3 to 4 times more likely to have another set! Nigeria has the highest rate of multiple births and more identical twins. A study shows vegans are five times less likely to have twins than women who consume dairy.
Examining 3D ultrasound images, a study in Padova, Italy found fetuses start deliberately interacting at 14 weeks. 40 % of twins invent their own language. Over 50 % of twins are born before 37 weeks. The average birth weight for a twin is 5 lb 5 oz.
