What does your clinic do to prevent multiple births? Do you closely monitor egg production before fertilization, or do you wait until you see how many eggs have become fertile? How much of this type of decision-making do you leave up to the patient?

P.R.

You do not specify if you are referring to in vitro fertilization (IVF) or ovulation induction and insemination. The options vary according to the patient's condition and treatment choice.

For the couple undergoing insemination, frequent ultrasound and blood estrogen determinations can help adjust medication doses to avoid stimulating the production of too many eggs. If too many egg follicles develop, some of the eggs can be removed, or the insemination attempt can be cancelled for that cycle. Some women choose to take their chances and consider selective fetal reduction if several fertilized eggs implant and begin developing.

With IVF, we limit embryo transfer according to the mother's age, embryo quality and stage of development. For example, the technique of blastocyst transfer on the fifth day after IVF retrieval allows us to transfer embryos that have a higher potential to implant; in such a case, we will transfer fewer embryos than we would with other techniques.

In my practice, I have careful discussions with my patients to ensure they understand the risk of multiple births and their options before deciding on the details of their treatment.