Forty-two patients, 26 controls, and their mothers were included (Table 1).
250 cases were initially recruited, but it was possible to interview the mothers in 42 cases (16.8%). In 208 cases no interview was possible because either the patients were no longer in contact with the service; their mothers were deceased, they were adopted, the mothers were abroad, clinicians did not recommend the interview, or patients and/or their mothers did not consent. The cases included were significantly younger than those not included (28.05 vs 32.65 p =0.006) with no other difference between the two groups.
Sociodemographic characteristics of cases and controls were reported in table 1. Cases were more frequently men (26, 61.9%) than controls (9, 34.6%, c sq = 4.79, P = 0.029), The mean age was 28.07 years (+8.52) at the time of onset. Greater prevalence of high and intermediate social class levels was found among controls (80% vs 56.4%, c sq=3.75, p=0.053). There were no other statistically significant differences among cases and controls.
Table 2 reports characteristics of mothers of cases and controls and frequency of the obstetric complications. The mean age of mothers at delivery was 26.88 years for cases and 28.46 years in controls. The mean paternal age was 31.08 for cases, and 31.81 for controls. Mothers were mostly married, working, homeowners, living with their partner and/or children. A more frequent history of medical disorders and use of drugs (12, 34.3% vs 3, 12.5%), particularly anti-inflammatory drugs (7, 20.6% vs 0, 0.0%), were more frequently found among mothers of cases compared with mothers of controls. Moreover, mother of cases (24, 57.1%) reported more frequently negative memories during pregnancy compared to mothers of controls (2, 7.7%). No other difference was found between mother of cases and mothers of controls.
The following associations were found to be significant by logistic regression analysis adjusted for sex and age:
- highly stressful situations during pregnancy (c sq=16.62, p=0.000), OR=16.0 (95%CI 3.3-76.6; p=0.001); the risk remains significant even when adjusted for age and gender in multivariate logistic regression analysis (OR=23.8, 95% CI 4.2-134.2,p=0.000);
- a lower level of maternal physical health before or during pregnancy (c sq=16.62, p=0.000), OR=16 (95%CI 3.3-76.6; p=0.001); the risk remains significant even when adjusted for age and gender in multivariate logistic regression analysis (OR=16.8,95% CI 3.3-86.0,p=0.001).
- use of anti-inflammatory drugs during pregnancy (c sq=5.61; p=0.018)
- low level of maternal education (c sq=5.49; p=0.019), OR =4.1(95%CI 1.2-14.2; p=0.024); the risk remains significant even when adjusted for age and gender in multivariate logistic regression analysis (OR=5.08,95% CI 1.3-20.5,p=0.023).
Experience of OCs prior to pregnancy was rare without significant differences between cases and controls.
The use alcohol during pregnancy was no different between the groups and there wasn’t any difference in cigarette consumption during pregnancy between cases and controls. Around half of the fathers smoked at home during pregnancy without any statistically difference. No mother admitted to having used any substance during pregnancy.
Most mothers nursed, in similar proportions between cases and controls. Patients' mothers breastfed for longer, for a mean of 6.85 months compared to 4.1 months for controls (t test = 2.083, p = 0.041). Alcohol was the most used substance (5, 14.3% of cases, 4, 17.4% of controls), followed by smoking (3, 8.1% in cases; 1, 4. 3% in controls) and medication (3, 8.8% in cases; 2, 8.7% in controls). The use of potentially risky substances (alcohol, medications and drugs) was not significantly different between cases and controls.
Infections during pregnancy were reported by 3 mothers (11.5%) of controls and 2 (4.9%) of patients. For both cases and controls, urogenital infection and influenza were the most common.
An excessive weight gain was found in 6 (14.6%) mothers of patients and 3 (11.5%) of controls.
There was a slightly higher incidence of OCs in mothers of patients than in those of controls without any statistically significant difference (14, 34.1 %, vs 6, 23.1%; c sq=0.931, p=0.335). Eight out of 14 OCs (19%) among cases and 4 (15%) out of 6 among controls occurred during pregnancy and consisted of a threat of abortion or ante-partum hemorrhage. OCs during delivery and postnatal period numbered 11 in cases and 7 in controls.