Effect of culture conditions and method of conception on mouse live birth rate.

Objective: To understand in a mouse model whether there are differences in the decidua and live birth rate after transfer of blastocysts generated by in vitro fertilization (IVF) or by superovulation with spontaneous mating into unstimulated recipients.

Design: Animal experiment.

Setting: University-affiliated tertiary hospital.

Sex-specific epigenetic profile of inner cell mass of mice conceived in vivo or by IVF.

The preimplantation stage of development is exquisitely sensitive to environmental stresses, and changes occurring during this developmental phase may have long-term health effects. Animal studies indicate that IVF offspring display metabolic alterations, including hypertension, glucose intolerance and cardiac hypertrophy, often in a sexual dimorphic fashion. The detailed nature of epigenetic changes following in-vitro culture is, however, unknown.

Oxygen concentration alters mitochondrial structure and function in in vitro fertilized preimplantation mouse embryos.

Study Question: Does the oxygen concentration in the culture medium [either physiologic (5%) or atmospheric (20%)] affect mitochondrial ultrastructure and function in preimplantation mouse embryos generated by IVF?

Summary Answer: Embryos cultured in 20% oxygen show increased mitochondrial abnormalities compared to embryos cultured in 5% oxygen.

What Is Known Already: ART are widely used and have resulted in the birth of more than 8 million children. A variety of media and oxygen concentrations are used to culture embryos.

Advanced Paternal Age Affects Sperm Count and Anogenital Distance in Mouse Offspring.

In Western society, couples increasingly delay parenthood until later in life. Overall, studies have focused on the reproductive performance of older parents or the impact of advanced maternal age on pregnancy outcomes, but few studies have examined how advanced paternal age (APA) affects offspring health. The aim of this study was to investigate the impact of increasing paternal age on offspring reproductive performance and long-term metabolic health in a mouse model.