Should a pregnancy test be required before scuba diving?

In recent years, scuba diving has become accessible worldwide. The average age of female scuba divers is similar to their window of fertility, and many women dive annually without knowing their pregnancy status. These women seek advice concerning the potential teratogenicity of diving, and whether they can continue the pregnancy. Nevertheless, little is known about the consequences of scuba diving on pregnancy, and the scientific literature is poor (old studies, 3 no controls, 4 few participants). Adverse pregnancy outcomes were observed in animal models, but were only conducted in late gestation. As a precaution principle, all international diving and medical organisations recommend avoiding scuba diving activity during pregnancy at any period of gestation. The aim of our study is to report on prenatal and postnatal characteristics of female scuba divers and pregnancy outcomes. We conducted a retrospective observational survey, including female members of different diving insurances and training organisations. A secured electronic questionnaire assessing sociodemographical and scuba diving data, general health and obstetrical history was sent to scuba diving women. Female divers were allocated to three different groups: womenwho (A) have never been pregnant; (B) had children but never dived while pregnant and (C) dived while pregnant. Pregnancy outcomes were compared between the last two groups. A total of 2239 scuba diving women answered our online survey; 1186 of them had never been pregnant (A), 587 had children but never dived while pregnant (B) and 466 dived while pregnant (C; table 1). Sociodemographical data and diving profiles were similar between groups (table 1). There was no difference observed in the miscarriage and premature birth rates between women who dived or did not dive during their pregnancy. There was, however, a significant difference identified in the rate of offspring malformations between women who dived (6 children affected), and those who did not dive during their pregnancy (none had malformation, p<0.01). All malformations, specifically heart, kidney and brain malformations, were derived from scuba dives during the first trimester of pregnancy. Multivariate analysis, power calculation and strengths and limitations are described in the web appendix. Despite precaution principles from all international diving and medical Table 1 Sociodemographic, diving and medical data of women who (A) have never been pregnant; (B) had children but never dived while pregnant; and (C) dived while pregnant