Does physical activity and sedentary behavior affect pregnancy outcomes after assisted reproduction?

This study investigated if physical activity (PA) or sedentary behavior (SB) affect fertility outcomes in women undergoing assisted reproduction (AR).

They found that PA and SB during AR did not affect fertility outcomes, while higher PA before AR was associated with higher ovarian response to stimulation.

Infertility is a growing problem worldwide. Assisted reproduction (AR) is used to treat infertility. The success of AR is approximately 30% per cycle. There is much interest in improving this. There are several factors that affect infertility. These include female age and genetics. Identifying factors that could improve fertility outcomes is important.

Physical activity (PA) is important for a healthy lifestyle. Sedentary behavior (SB) is associated with reduced health. SB describes low or absent PA, an increased period of time spent in front of a screen (TV, computer, telephone). Balancing SB and PA is important. Some studies suggest increasing PA improves fertility outcomes. Many of these studies involved patient reports of PA. These can be biased. The role of SB on fertility outcomes has not been investigated. It is unclear if PA and SB before, during, or after AR affect fertility outcomes. 

This study included 101 women undergoing AR. All patients underwent controlled ovarian stimulation (COS). In vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) was then performed. Women wore an accelerometer device during the study. This measures PA and SB. The time spent using a screen (screen time; ST) was also used to measure SB. The main fertility outcomes included live birth (LBR) and clinical pregnancy rate (CPR). The number of oocytes harvested was used to measure COS success. 

PA levels reduced and SB increased during IVF. Higher PA and lower SB was associated with better COS outcomes. The number of oocytes and embryos obtained was significantly lower in women with higher ST (7 hours a day or more in non-work days). However, PA and SB were not associated with LBR or CPR.

The authors concluded that PA and SB did not affect pregnancy or birth rate, but higher PA and lower SB were associated with better ovarian stimulation results.

The number of patients in this study was low. Larger studies are needed.