Population and data collection
In this epidemiologic, monocentric, observational, longitudinal and
retrospective study, data derive from the administrative and medical
databases of the University Hospital of Martinique, which is the main
obstetric center in Martinique dealing with an average of 3050 births
per year, over an average of 3600 births per year out of a population of
approximately 380 000 inhabitants. Pregnant women residing in
Martinique, a French Caribbean oversea Island were recruited from the
Mother and Child Centre of the University Hospital of Martinique. Mean
age, body mass index (BMI), tobacco use, medical and surgical
information as well as specific information regarding the pregnancy and
obstetrical history and complications of the ongoing pregnancy were
recorded. We restricted the study to those with pregnancy (determined by
ultrasound dating scan before 12 weeks and date of delivery) during the
period from 25/01/2016 to 31/07/2020. To be included in the present
study, the women had to have at least 18 years old, a gestational age of
20 weeks or more, and be registered and followed-up at the CHUM Mother
and Child Centre. From the eligible population, we excluded the women
who were unable or refuse to consent and having pregnancy with more than
two baby at a time. We also excluded those women with moving
geographical location during the pregnancy period, making difficult to
determine the actual exposure to air H2S pollution.