Infant Suffocation Incidents Related to Co-Sleeping or Breastfeeding in the Side-Lying Position in Japan.

Co-sleeping and breastfeeding in the side-lying position have recently been pointed out as risk factors for suffocation in sleeping infants; however, there is no actual report on an "incident." "Incident" is defined as a tense or sobering experience without a consequential fatal suffocation accident. It is important to understand infant suffocation incidents to prevent accidents during co-sleeping and breastfeeding in the side-lying position. We investigated factors and frequency of infant suffocation incidents associated with co-sleeping and breastfeeding in the side-lying position using a self-administered questionnaire survey of 895 mothers during their infant's 1-, 4-, or 10-month health checkups. Co-sleeping and breastfeeding in the side-lying position were practiced by 28.3% and 56.0% of mothers, respectively; thus, 84.3% of the mothers surveyed were practicing either co-sleeping or breastfeeding in the side-lying position. Of those who received guidance from a medical professional, 36.1% practiced only co-sleeping while 60.1% practiced only side-lying breastfeeding. In the co-sleeping group, 10.6% had faced infant suffocation incidents, while 13.2% in the breastfeeding in the side-lying position group had faced similar incidents. Regarding factors associated with suffocation incidents while co-sleeping, the frequency of occurrence was significantly more in mothers of 1-month and 4-month-old infants compared with those of 10-month-old infants. Of mothers who faced suffocation incidents while breastfeeding in the side-lying position, 45% also had faced similar incidents while co-sleeping. These results demonstrate the importance of thoroughly educating mothers about the risks associated with co-sleeping and breastfeeding in the side-lying position for preventing infant suffocation.

The Current Status of Postpartum Menstrual Resumption Delay and Associated Risk Factors in Japanese Women: An Adjunct Study of the Japan Environment and Children's Study.

Background: Prolonged postpartum amenorrhea is a sign of secondary infertility. However, there are no reports on postpartum menstrual resumption delay in Japanese women. We conducted an Adjunct Study of the Japan Environment and Children's Study (JECS) to elucidate the actual state of postpartum menstrual resumption delay in Japan and related factors. Methods: An Adjunct Study questionnaire was sent to 2,729 mothers who participated in the study of Shinshu Subunit Center in the JECS, and 762 mothers were included in the analysis. The participants were categorized into the normal and delayed groups based on the weeks of postpartum menstrual resumption. To investigate the factors associated with postpartum menstrual resumption delay, a multiple logistic regression analysis was conducted with the weeks of postpartum menstrual resumption as the dependent variable. Results: The study included 762 women, of which 61 (8.0%) had delayed menstruation, not occurring until 72 weeks postpartum. The multivariate analysis revealed a significant correlation between postpartum menstrual resumption delay and age at delivery, past history of irregular menstruation, history of taking oral contraceptives, breastfeeding at 18 months, and the level of satisfaction with the husband's participation in childcare. Conclusion: Postpartum menstruation in Japanese women occurred later than before. In addition to previous findings, another factor was the husband's satisfaction with his participation in childcare. We should not only focus on the physical aspects of mothers, but also provide midwifery care that proposes and supports family planning suitable for each family.