Background In the UK the incidence of psychiatric illness in women is increasing. There is limited information on pregnancy outcomes in these women.

Aims To determine the prevalence of psychiatric illness in women who attend for ante-natal care and to examine pregnancy outcomes.

Method Data were collected from 221 women who booked in Ninewells Hospital, Dundee in December 2012. Information on pregnancy outcomes was obtained from the maternity case notes. Outcomes for women with pre-existing psychiatric morbidity were compared to the remaining cohort.

Results Complete data were available for 195/221(88%). 34/195(17%) reported current or past psychiatric history. 28/34(82%) had depression.

10/34(29%) women with pre-existing psychiatric illness had SVD compared to 74/161(46%) in the control group [RR = 0.89, 95% CI = 0.78–1.01, p = N/S]. 13/34(38%) required caesarean section compared to 42/161(26%) [RR = 1.1, 95% CI = 0.95–1.31, p = N/S]. 11/34(32%) required operative vaginal delivery compared to 45/161(28%) [RR = 1.04, 95% CI = 0.89–1.21, p = N/S].

For women with psychiatric illness, median gestation at delivery was 39 weeks (Range = 24–41 weeks). 13/34(38%) had induction of labour (IOL) compared to 32/161(20%) [RR = 1.21, 95% CI = 1.0–1.47, p = 0.03]. The median birth weight for women with psychiatric illness was 3115g (Range = 910–4320 g).

There were no differences in the rates of pre-term birth, stillbirth, perineal trauma and post-partum haemorrhage, and no differences in perinatal morbidity.

Conclusions Almost 1 in 5 women attending for ante-natal care has a history of psychiatric illness. There was a high rate of obstetric interventions, but other than IOL, none reached statistical significance. It is reassuring to note that women with pre-existing psychiatric morbidity do not appear to be at risk of adverse perinatal outcome.