The Benefit Of Transferring Just One Embryo


In 2010 RSC pregnancy rates for women under the age of 35 transferring two blastocyst embryos have been 60 percent with half of those pregnancies twins (too high!). For women under the age of 35 transferring a single blastocyst embryo, pregnancy rates have been 55 percent with only one twin pregnancy (developing from a single embryo splitting).

With embryos from an egg donor, pregnancy rates transferring rqo blastocyst embryos have been 80 percent with 40 percent of those pregnancies twins, and transferring a single blastocyst embryo pregnancy rates have been 64 percent.

Clinical Pregnancy Rate per Embryo Transfer

1 embryo transfer (ESET) 2 embryos transferred
IVF < 35 yo 55% 60% (48% twins)
Egg Donation Recipient 64% 80% (42% twins)


Though many patients going through infertility treatment say they really want twins, twin pregnancies are higher risk than single pregnancies. They are particularly at risk for premature labor and delivery. Twins are born on average 4-5 weeks before the calculated due date (nine months), but can be born much earlier. With early delivery the babies are at much greater risk of having problems with their lungs, heart, eye sight, and other developmental abnormalities. They often require hospitalization in the Neonatal Intensive Care Unit for sometimes weeks or months. Many obstetricians will also require that patients with twin pregnancies go on bed rest for the last 2-3 months of the pregnancy.

In an infertility practice, we hear patient stories every month about their twins being born very prematurely, having significant problems and sometimes even dying.

Because of this, we feel a single healthy pregnancy is the best outcome from IVF.

At RSC our experienced and highly successful laboratory has allowed us to recommend single embryo transfer to many IVF patients. Best candidates for ESET are women under the age of 35 or egg donation recipients, who have multiple high quality blastocysts (day 5 embryos) available for transfer.

In addition these patients have blastocyst embryos frozen, and at RSC our pregnancy rates with frozen embryos are almost the same as with fresh embryos. So they have extra embryos for a future pregnancy, or if they do not get pregnant on the first try, they can try again at a much lower cost.

At RSC we feel comfortable recommending a single embryo transfer to many patients because our experience and success allow us to do so without compromising your chance for pregnancy. And by transferring only one embryo we can help improve the chance that your pregnancy will be a lower risk single pregnancy, with the goal of having a healthy baby.

Mother kissing little baby at home

Breaking Barriers, Building Families

Since 1983, we have pioneered fertility treatment for every kind of family. We want to help you achieve your dream of having a baby.

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