Exposure in Health Care: Pregnancy Outcome and Fertility Marja-Liisa Lindbohm Finnish Institute of Occupational Health

Health care work: exposures Chemicals: anesthetic gases, antineoplastic agents, sterilizing agents, solvents, mercury Radiation Biological agents Physical strain Irregular working hours

Reproductive effects of anesthetic gases in several human studies exposure related to spontaneous abortions congenital malformations reduced fertility in women in some studies exposure related to reduced birth weight increased risk of small for gestational age spontaneous abortion among the wives of exposed men and malformations in their offspring

Anesthetic gases and spontaneous abortions: a meta-analysis (Boivin 1997) 19 studies published in 1971 – 95 Relative risk 1.48 (95% CI 1.4 – 1.58) Analysis limited to 6 most valid studies: relative risk 1.9 (95% CI 1.72 – 2.09) Conclusion: the available data suggest that a real risk may be present

A study of dental assistants exposed to nitrous oxide (Rowland et al 1992, 1995) 7000 dental assistants Telephone interview, 69% responded Reduced fertility in women exposed to  5 hours per week to unscavenged nitrous oxide Increased risk of spontaneous abortion among women exposed  3 hours per week to unscavenged nitrous oxide

A study of midwives exposed to nitrous oxide (Ahlborg et al 1996, Bodin et al 1999) 3985 midwives A mailed questionnaire, 84% responded Reduced fertility in women assisting >30 deliveries/month (FR 0.63, 95%CI 0.43 – 0.94) No increased risk of spontaneous abortion Reduced birth weight (-77 gm, 95%CI –129,-24) and increased risk of infants being small for gestational age (OR 1.8, 95%CI 1.1 – 2.8)

Enflurane, etomidate, fentanyl, halothane, isoflurane, propofol, sevoflurane, thiopental Data limited and no human studies on the effects of occupational exposure to these agents Halothane: increased frequency of developmental delay in some experimental studies, but not all, and behavioral abnormalities among the offspring Enflurane and isoflurane evaluated: animal data show that no classification for toxic to reproduction is indicated Thiopental: no increased risk of malformations in women treated during pregnancy

Suggested new guidelines for concentrations of anesthetic gases during pregnancy in Finland Nitrous oxide10 ppm (TLV for all:100 ppm) Halothane0,1 ppm (TLV for all: 1 ppm) Desflurane10 ppm Enflurane10 ppm Isoflurane10 ppm Sevoflurane10 ppm

Anesthetic gases: exposure assessment Exposure may be high in: operating rooms with poor ventilation or no efficient scavenging equipment delivery rooms administration of anesthesia to small children in arms veterinary operating rooms dental offices

Antineoplastic agents and reproductive health increased risk of malformations and reduced probability of live births in treated patients teratogenic in animal experiments occupational exposure related to: menstrual dysfunction infertility spontaneous abortions congenital malformations

Maternal occupational exposure to antineoplastic agents and spontaneous abortion StudyNumber of exposed pregnancies RR or OR95% CI Selevan et al / Stücker et al Valanis et al Skov et al

Antineoplastic agents: hazard assessment Exposure may be high in: dilution and preparation of the solutions cleaning of the preparation room injection/infusion of the drugs handling of the excreta of patients Guideline: a pregnant worker should not do these jobs

Ethylene oxide and adverse pregnancy outcome Used as a sterilant in hospitals, and in medical and dental offices Mutagenic, teratogenic and carcinogenic agent Increased risk of spontaneous abortion in exposed hospital sterilising staff and dental assistants Increased risk of preterm and postterm birth Exposure should be avoided

Maternal exposure to solvents in laboratories or health care sector and spontaneous abortion

Ionizing radiation and pregnancy outcome High doses known to be harmful to reproductive health Findings on the reproductive effects of occupational exposure are contradictory increased risk of spontaneous abortion reported among veterinarians and radiology technicians no excess of malformations or cancer in children of radiographers, but a slight increase of chromosomal anomalies other than Down

Ionizing radiation: exposure assessment The protection of the fetus must be comparable with that provided to the members of the public The equivalent dose of radiation should not exceed 1 mSv during the remainder of the pregnancy Recommendation: a pregnant worker should not hold patients during x-ray or give regularly isotope treatment

Non-ionizing radiation and adverse pregnancy outcome Physiotherapists may be exposed to short-waves, microwaves and ultrasound MRI technologists may be exposed to strong static magnetic fields Evidence on their adverse reproductive effects is inconclusive Increased risk of spontaneous abortion and low birth weight related to use of short-wave equipment EU guideline: exposure to short waves should be minimised

References on exposures in health care and reproductive health Figà-Talamanca I. Reproductive problems among women health care workers: epidemiologic evidence and preventive strategies. Epidemiologic Reviews 2000;22: Boivin J-F. Risk of spontaneous abortion in women occupationally exposed to anesthetic gases: a meta- analysis. Occup Environ Med 1997;54: Ahlborg G, Hemminki K. Reproductive effects of chemical exposures in health professions. J Occup Environ Med 1995;37: