Effects are limited. Drugs taken to increase the chances of pregnancy can result in multiples in that pregnancy however, the number of babies depends on many things such as the type and dose of drugs and a woman's response to them. Also doctors cannot predict with certainty the number of babies born if fertility drugs were taken because an embryo might not develop in some cases. High-order multiple gestation is rare.
NO, With ovulation treatment there is a greater risk of multiple births. The risk is greatest in women with pcos (polycystic ovary syndrome). But, with diet, exercise and metformin, we can restore ovulation in up to 85% of women with this condition and dramatically reduce the risk.
No. Previous fertility treatments will not increase your chances of having multiples. Drugs taken for infertility treatment only effect the current treatment cycle. So have no fear about being the next octomom when you try to conceive after stopping fertility therapy.
No. The case of "octomom" was due to her "fertility doctor" placing a high number of embryos in her uterus. Prior treatments will not increase your current odds of a multiple pregnancy.
No. As long as both you and your doctor agree only transfer one embryo back each time, you will have very low chance to have multiple multiple pregnancy.
No. My wife and I have one single son as a result of several rounds of infertility treatments.
No. Not unless you go to california and have 12 frozen/thawed embryos placed at the same time. All kidding aside, multiple pregnancy rates are more common the more fresh or frozen embryos you have placed into your uterus. Injectable medications with inseminations, in my practice, result in triplet+ rates of 7%. Triplet or more rates are very rare with oral medications. Discuss all with your physician.