Asthma, anxiety and depression in pregnancy : the impact on pregnancy, delivery and perinatal outcomes

Abstract

Asthma and mood disorders such as anxiety or depression are associated with adverse pregnancy, delivery, and perinatal outcomes. There is an association between mood disorders and asthma and there may be common mechanisms on how the conditions affect pregnancy outcomes. For example, some of the associations may be explained by genetic or environmental factors, familial confounding. In this thesis we have investigated how asthma and anxiety or depression complicates pregnancy and delivery outcomes in a combination of large population-based registers and smaller clinical cohorts, using family design methods to adjust for possible shared genetic and environmental factors.

In Study I and II we studied the associations between maternal asthma and adverse pregnancy outcomes, such as preeclampsia, placental abruption, mode of delivery, birth weight, and gestational age, using Swedish population-based cohorts. For Study II we identified cousins and siblings who were pregnant and gave birth during the same study period. We found that maternal asthma was associated with many of the adverse outcomes, such as preeclampsia (Study I, II), and that the associations were not confounded by factors shared within families (Study II). There were also increased risks for some adverse outcomes based on asthma severity and control (Study I).

For Study III we investigated the impact of maternal asthma on early foetal growth, assessed by routine ultrasound scan in second trimester. The study population originated from the MAESTRO study of 1693 women prospectively followed during pregnancy. We did not find any significant effect of maternal asthma on early foetal growth. There was also no difference between women with and without asthma for birth weight and gestational age.

In Study IV, we estimated the association between maternal anxiety or depression and pregnancy outcomes using a population-based cohort. We found that maternal anxiety or depression was associated with several adverse pregnancy outcomes and that the associations were not confounded by familial factors shared by cousins and siblings. There was no interaction between asthma and anxiety or depression for any of the outcomes except for elective caesarean section. There were also higher odds for elective caesarean section in women with anxiety or depression diagnosis without medication compared to those with medication.

In conclusion, maternal asthma as well as maternal anxiety or depression were associated with several serious pregnancy complications and adverse perinatal outcomes. Familial confounding did not explain the observed associations. Apart from elective caesarean section, we did not see any interaction between maternal asthma and anxiety or depression on the studied adverse pregnancy outcomes. This means that targeting the asthma disease as well as anxiety/depression in the pregnant woman will continue to be important in reducing risks for adverse outcomes in pregnancy. Greater awareness and proper management would most likely improve outcomes