Fertility researchers can predict which pregnant women are at greatest risk of miscarriage

Fertility scientists gathered in Stockholm last week to present their latest research on in vitro fertilization, high-risk pregnancies and other topics at the European Society of Human Reproduction and Embryology conference.

Among the highlights:

* British researchers have figured out a way to assess which pregnant women are at greatest risk of miscarriage.

After studying 112 high-risk women during their sixth through 10th weeks of pregnancy, the researchers determined that the amount of a woman’s bleeding and her level of the hormone chorionic gonadotrophin could be combined into a “pregnancy viability index” that accurately predicted which women would go on to continue their pregnancies in 94% of cases as well as which would have miscarriages in 77% of cases.

* IVF embryos that are frozen and then thawed before being transferred to the uterus are more likely to grow into newborns that are bigger and heavier than newborns that were never frozen as part of the IVF process.

Researchers from France analyzed more than 16,000 births and found that so-called “cryo babies” weighed nearly 3.6 ounces more, on average, than babies born from embryos that were never frozen. In addition, researchers from Denmark looked at roughly 15,000 births to figure out that nearly 17% of cryo babies were born large for their gestational age, compared with 10.3% of other IVF babies and 11.4% of babies conceived the old-fashioned way.

* Women who are tall are more likely than shorter women to give birth to twins if they have two embryos transferred to the uterus during IVF.

The finding is based on data from 2,357 Dutch women who had double-embryo transfers, resulting in 371 singleton pregnancies and 125 twin pregnancies. The cutoff for being “tall” was more than 5 feet 7 inches.

For more news from the meeting, check the conference’s press site.