Shift work, fetal development and course of pregnancy

Area of Science:

• Occupational Health
• Reproductive Epidemiology
• Perinatal Studies

Background:

• Shift work is prevalent, raising concerns about potential adverse effects on maternal and infant health.
• Previous research on shift work and pregnancy outcomes has yielded mixed results, necessitating further investigation.

Purpose of the Study:

• To investigate the association between rotating shift work and adverse pregnancy outcomes, including congenital malformations.
• To explore the impact of shift work, noise exposure, and their interaction on pregnancy complications and infant size.

Main Methods:

• A case-control study involving 1475 mothers of infants with structural malformations and 1475 mothers of normal infants.
• Data collection included the Finnish Register of Congenital Malformations and detailed interviews on maternal work conditions, including shift schedules and noise exposure.

Main Results:

• No evidence of a teratogenic risk associated with shift work was found.
• Rotating shift work alone was not linked to threatened abortion or pregnancy-induced hypertension, but moderate risks were observed in noisy environments.
• A slight excess of babies small for gestational age was associated with rotating shift work, independent of noise.

Conclusions:

• Rotating shift work may pose a slight risk for delivering babies small for gestational age.
• The combination of rotating shift work and noisy environments may increase the risk of threatened abortion and pregnancy-induced hypertension.
• Further research into the effects of various work schedules on pregnancy outcomes is warranted.