Will I have a multiple pregnancy if I undergo fertility treatment?
At Bubtree we strive to minimize the likelihood of treatment resulting in a multiple pregnancy, because risks in pregnancy and after birth are increased for both the mother and babies in association with a multiple pregnancy. Multiple pregnancy occurs naturally in around 1.2% of pregnancies. The incidence of multiple pregnancy is increasing in the general population, and this is thought to be due to two main factors - increasing maternal age (mothers aged over 35 are more likely to have a multiple pregnancy than younger women), and certain fertility treatments.
Some fertility treatments are associated with an increased risk of multiple birth. The incidence of multiple pregnancy (including twins, triplets, quadruplets, and quintuplets) is much greater (around 10-20%) when conception occurs during a cycle in which medication is taken.
In IVF the number of fertilized eggs (embryos) used for treatment is controlled and so with IVF the risk of higher order multiple birth is considerably less. If one day five embryo (blastocyst) is transferred inside the woman's uterus then the risk of multiple pregnancy is around 5% of pregnancies (which can rarely be triplets or more). If two blastocysts are transferred then 40% of resulting pregnancies are multiple, with perhaps as much as 33% of pregnancies being triplets, quads or more. Because of this, at Bubtree we usually transfer one day 5 embryo (blastocyst), and cryopreserve (freeze) any extra good quality embryos. In this way, we minimize the risk of multiple pregnancy occurring.