The findings come from the Avon Longitudinal Study of Parents and Children (ALSPAC), which prospectively followed women who became pregnant between 1990 and 1992 (G0) in a region in southwest England.
In the current analysis, the researchers examined 180 daughters of the original participants, or the female partners of male children (G1). They were recruited during a pregnancy that occurred between June 6, 2012, and Dec. 31, 2016, and had to have completed the Edinburgh Postnatal Depression Scale (EPDS) at 18 weeks of the pregnancy. They were compared to G0 mothers who had become pregnant in the same age range as the G1 subjects (age 19-24 years). Because the G1 participants had all been born in the county of Avon, the G0 subjects were also restricted to 2,390 women who were born there, which represented about 50% of the G0 sample.
Seventeen percent of the G0 women had high depression scores (EPDS greater than or equal to 13) at 18 weeks, compared with 25% of the G1 women. After adjustment for age, body mass index, smoking, parity, and education, the risk ratio for prenatal depression in the later generation of women was 1.77 (95% confidence interval, 1.27-2.46).
There was a strong association between prenatal depression in G1 women and their mothers: Fifty-four percent of women whose mothers had experienced prenatal depression also were positive for prenatal depression, compared with 16% of women whose mothers did not have prenatal depression (RR, 3.33; 95% confidence interval, 1.65-6.67).
An increased incidence of prenatal depression has major implications for service providers and public health efforts. The authors of the study call for more research to confirm this increase and identify potential causes.
The study is the first multigenerational cohort look at prenatal depression, but was limited by the much smaller size of the G1 group. The study also may not be generalizable to older women or ethnic groups other than white European individuals, and selection bias is possible.
The Avon Longitudinal Study of Parents and Children was supported by the UK Medical Research Council, the Wellcome Trust, and the University of Bristol. This current study received support from the National Institute for Health Research Biomedical Research Centre at the University Hospitals Bristol National Health Service Foundation Trust and the University of Bristol, the National Institutes of Health, and the European Research Council under the European Union’s Seventh Framework Programme. Dr. Pearson reported no relevant financial disclosures; a number of the other researchers reported support from a variety of grants.
SOURCE: RM Pearson RM et al. JAMA Network Open. 2018;1(3):e180725.