Selective Fetal Reduction: A Difficult Decision to Make

17 Aug
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The introduction of ovulation induction drugs such as clomiphene citrate and urinary-derived gonadotropins (menotropins) in the 60’s, followed about 15 years later by in vitro fertilization (IVF), markedly improved the success of infertility treatment, but at the same time it heralded a virtual explosion in the incidence of multiple gestations. In spite of this, the likelihood in any given case of achieving a viable pregnancy by these methods still remains somewhat unpredictable. Because of the high cost of IVF treatment in the United States (>$12,000 per cycle) coupled with a relatively low birth rate, there is a tendency for couples undergoing IVF as well as doctors performing IVF to transfer multiple embryos to the uterus in hopes of maximizing success potential.

The downside to this practice, of course, is the risk of high-order multiple gestations (triplets or greater) and the substantial toll it takes on mothers, their premature babies and on the healthcare system. The short and long-term health risks that the babies face is also a tremendous financial burden to the family and to society, as many of these babies face the prospect of “cradle to grave” medical care due to prematurity-related medical conditions. The cost of providing such care approaches one billion dollars per year in the United States alone.

It has been reported that in about 40% of high order multiple pregnancies, one or more of the babies will either not survive the neonatal period or will suffer chronic from physical and/or neurologic complications associated with premature birth. The magnitude of the problem is further evident from statistics’ that show that from 1980-1997 the number of annual live babies born from twin gestations rose 52%, while the incidence of high-order multiple gestations (triplets or greater) increased by 404%.

Such a prospect often prompts prospective parents to consider selective fetal reduction in the case of a high-order gestation. Though a heart-rending decision, it is a relatively safe procedure whereby it is possible to reduce the number of concepti in the uterus without harming the remaining one(s). It involves the injection of a lethal chemical under guidance by ultrasound, directly into the heart chamber(s) of one or more developing concepti around the end of the first trimester of pregnancy. This results in the conceptus immediately succumbing whereupon it is slowly absorbed over a number of weeks, without doing harm to the surviving concepti. Provided that it is not done to reduce “monozygotic”(identical) multiples that share the same blood supply, and is conducted by an expert , selective fetal reduction rarely (i.e. in less than 5% of cases) results in a miscarriage.

The only sure way to avoid the risk of high order multiple pregnancies is to insure that too many embryos do not reach the uterus. With IVF this can be achieved by limiting the number of embryos transferred. However, when it comes to methods of ovulation induction that do not involve IVF (e.g. the use of fertility drugs alone or in combination with intrauterine insemination), it is not possible to prevent this problem from occurring.

The problem of mandating that no more than 2 embryos be transferred lies in the fact that since embryo quality declines with the age of the egg provider age, such a limitation would markedly reduce the chance of IVF success in women over 40 years of age, burdening them with the physical, financial and emotional cost associated with having to often undergo numerous attempts in order to achieve their goal.

Unlike with IVF (where it is possible to deliberately limit the number of embryos reaching the uterus), the same does not apply when fertility drugs are used for ovulation induction in the non-IVF setting. Therefore in such cases it is not possible to strictly control the number of ovulations that might occur.

I would respectfully submit that given the gravity of the risks associated with high order multiple pregnancies, selective fetal reduction might perhaps be described as a moral decision whose purpose it is to optimize the quality of life after birth. Furthermore, given the heart- rendering nature of such a decision, it should perhaps even be regarded as a brave and laudable attempt to optimize the quality of life after birth.


  • Stacy says:

    Dr. Sher,
    I am 43 and pregnant with twins, almost 12 weeks. I go in for testing and meeting a doctor at Fetal Maternal health in the Seattle area. I have been encouraged to ask about reduction to a singleton. Could you tell me the average risk of miscarriage to the remaining embryo. I am aware that my doctor will take my health and personal issues into consideration and advise me, however I am new to this idea and though and have just begun research. This is my first child, conceived without fertility treatment after taking a break from fertility medications for 7 unsuccessful months. Any advice or good questions I should be asking? Thanks, Stacy
    p.s. thank you for your website!!

    • Geoffrey Sher says:

      Thank you for connecting! I am updating my entire blog, so kindly-go to and re-post your question/comment there, and I will respond promptly. Henceforth I will be responding on that site.

      Thank you.

      Geoff Sher

  • Mar says:

    I am travelling to miami because I am carrying 4 embryos could you please give me all information where I can get a selective reduction

    • Geoffrey Sher says:

      Today most large metropolitan areas will provide that service. Certainly Miama will have several places. Ask your Re to refer you to such a center.

      Good luck and G-d bless!

      G4eoff sher

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