The study was led by researchers from McGill University.

A total of 111 parents (54 couples and 3 mothers of single-parent families) participated in the study published in the Journal of Sleep Research led by McGill doctoral student Samantha Kenny under the supervision of Marie-Helene Pennestri, Assistant Professor in the Department of Educational and Counselling Psychology.

Participants' sleep patterns were studied for two weeks. Mothers with one baby reported having less interrupted and better-quality sleep than mothers with more than one child, although the total amount of sleep did not differ depending on the number of children. No difference was noted in fathers.

"Experienced mothers perceived their sleep to be more fragmented than that of first-time mothers. Tension in the marital relationship may transpire if childcare is one-sided and not discussed collaboratively," says Pennestri, who is also a researcher at the Hopital en sante mentale Riviere-des-Prairies (CIUSSS-NIM).

According to the researchers, interventions developed by healthcare providers targeting an equal distribution of daytime and nighttime childcare tasks could be helpful. These interventions should be tailored to each family member, depending on their situation.

As next steps, the researchers aim to explain the differences between mothers and fathers, and determine why mothers with more than one child report worse sleep.