Your Guide For A Child t July 2022 06 Sperm switch swimming patterns to locate egg A new study reveals how sperm change their swim- ming patterns to navigate to the egg, shifting from a symmetrical motion that moves the sperm in a straight path to an asymmetrical one that promotes more circular swimming. This change in behavior, called hyperactivation, en- ables the sperm to sweep the area once in the egg's proximity, which improves the sperm's chances of finding it. For the in vitro study, the researchers designed mi- crofluidic chips with micron-sized channels so they could observe bovine sperm with a microscope and a high-speed camera. By exposing the mechanisms involved, the study not only unravels a mystery of how the sperm navi- gates to the egg, but it also has implications for human in-vitro fertilization and dairy cow reproduc- tion and provides new information for engineers to design robotic micro swimmers. Low birth weight among IVF children not linked to infertility treatments Children conceived through medically assisted reproduction are more likely to be born premature and are at greater risk of being born small than naturally con- ceived babies, according to new research. However, the study of almost 250,000 U.S. families finds that differences in birth weight and pregnancy term between medically assisted reproduction (MAR) -- including techniques such as IVF treat- ment, artificial insemination and fertility-enhancing drugs -- and naturally con- ceived children become insignificant once family circumstances are considered. The study found that children who were conceived through MAR were 10% more likely to be born premature and had 9% greater odds of being born small than naturally conceived infants. More invasive treatments -- such as assisted re- production and artificial insemination -- were more strongly associated with ad- verse birth outcomes, whereas infants conceived using fertility-enhancing drugs were more similar to those who were naturally conceived.