Dataset from Dalla Vecchia LA, De Maria B, Cassetti G, Clementi L, De Grazia V, Perego F, Porta A. How the first years of motherhood impact the cardiac autonomic profile of female healthcare professionals: a study by heart rate variability analysis. Sci Rep. 2021 Apr 14;11(1):8161. doi: 10.1038/s41598-021-87596-y. PMID: 33854133; PMCID: PMC8047021. Abstract The conciliation between career and family is a relevant issue for working women, in particular during the first years of motherhood. Data about the state of the cardiac autonomic regulation in working women with preschoolers are lacking. Aim of this study was to compare the cardiac autonomic profile of female healthcare professionals with and without preschoolers via the analysis of the variability of the time distance between two consecutive R-wave peaks (RR) from standard 24-h Holter electrocardiogram (ECG). Fifty healthy active female healthcare professionals were enrolled: 25 with at least one preschooler (W_KID) and 25 without (W_NOKID). A standard Holter ECG was obtained during a regular working day. Segments of 5000 consecutive RRs were selected during daytime (DAY) and nighttime (NIGHT). Heart rate variability analysis was performed and the following parameters were considered for comparison between the two groups: mean (��RR), variance (��2RR), and the absolute power in high frequency component (HF) of RR (HFRR) series. HFRR was considered as a marker of vagal cardiac modulation. Only ��RR significantly increased from DAY to NIGHT in both groups (699 �� 88 vs 887 �� 140 ms in W_KID and 728 �� 90 vs 942 �� 166 ms in W_NOKID). Instead, ��2RR and HFRR increased from DAY to NIGHT only in W_NOKID (from 3334 �� 2153 to 4816 �� 4063 ms2 and from 356 �� 334 to 1397 �� 1629 ms2, respectively). W_KID showed lower ��2RR and HFRR during NIGHT, compared to W_NOKID (2336 �� 3170 vs 4816 �� 4063 ms2 and 556 �� 950 vs 1397 �� 1629 ms2, respectively). The perceived stress according to the visual analogue scale was similar in the two groups (4.7 �� 2.1 in W_KID, 5.7 �� 2.1 in W_NOKID). The presence of preschoolers lowered nocturnal cardiac vagal modulation in female healthcare professionals. This might represent an adaptation with a finalistic purpose, scilicet the facilitation of a prompt reaction in case of a child's need.