Avoiding Twins Following Fertility Treatment requires careful consideration of fertility treatment options
Many couples try to avoid twins for many reasons:
1) Baby related: preterm delivery, before 37 weeks, that may result in prematurity, need for a long intensive treatment and possible neurological impairment and other diseases.
2) Mother related: twin pregnancy is more risky than singleton.
3) Social reasons: financial, emotional and personal burdens on the family.
Counseling from reproductive endocrinologists about the risk of multiple pregnancy is very important before initiating fertility treatment.
Twins can be avoided with fertility treatment (Selective Reduction) by avoiding injection medications during IUI cycles, single embryo transfer during IVF cycles and fetal reduction if twin pregnancy takes place.
The chance for twin pregnancy following fertility treatment can be minimized or avoided if one
1) Avoid treatments that cause multiple embryos to reach the uterus and / or
2) Fetal reduction of twins to singleton
Avoiding Twins Following Fertility Treatment : do not allow multiple embryos to reach the uterus
Fertility treatments include IUI and IVF.
1) IUI. The ovaries are stimulated for 10 days or so then sperm is concentrated and injected inside the uterus. Risk for twins increase with the use of injection medication (30%) versus oral medicine (clomid 8%). The risk is also higher in the first cycle versus later cycles, in younger women, wemen with PCOS, when many large follicles (> 14mm) on ultrasound and with high estrogen levels. Even when with meticulous monitoring of stimulation, the risk of twins is not zero.
2) IVF. The ovaries are stimulated and retrieved, fertilized in the lab then one or more embryos are transferred in the uterus. The number of embryos transferred is selected based on the implantation potential per embryo. Embryo implantation is related to female age and morphology or shape of the embryo. When one embryo is transferred (elective single embryo transfer) the risk for twins is (1%) due to embryo splitting versus about 30% when two embryos are transferred. The American Society for Reproductive Medicine recommend single embryo transfer for younger women with good quality embryos. Single embryo transfer should be considered for all women who want to avoid twins.
Avoiding Twins Following Fertility Treatments : Fetal Reduction
Fetal reduction means one pregnancy sac is removed from the uterus while the other sac is left. First there is the option is of CVS. The sacs are sampled and tested for their chromosomes to select the normal ones. The procedure of reduction is performed using a needle not surgery. Studies showed that reduction prolongs pregnancy and improve survival and quality of the remaining babies even when 5% chance of loosing both babies due to the procedure is considered. This is not abortion. This is an attempt to give the remaining babies better chance at survival and healthy life.
Know your personal risk for multiple pregnancy, Avoid using injection medication for IUI, consider single embryo transfer after IVF and if pregnant with twins consider fetal reduction.
DR. AMR AZIM
Amr Azim, MD, FACOG is a reproductive endocrinologist and a fertility specialist with special training in treating simple and complex fertility problems. His areas of expertise are assisted reproduction and preservation of fertility.