Denial of pregnancy is the fact that a pregnant woman does not become aware of her pregnancy until the second trimester and sometimes only on the day of delivery. The lack of follow-up can then suggest that she and her child are exposed to an increased risk of complications.

The objective was to evaluate the maternal and perinatal morbidities of the denial of pregnancy, compared to women who not deny their pregnancy.

This is a retrospective, observational, case-control type, unicentric study carried out at the University Hospital of Caen from January 1, 2002 to April 30, 2022. The exposure variable was the fact of having denied pregnancy and any woman having had a pregnancy discovered beyond 14 WA and 6 days and giving birth during the study period was included in the group of cases. Twin pregnancies and pregnancy concealed or insufficiently or even not voluntarily supported were excluded.

Were included 137 singleton pregnancies in each group discovered. There is a rate of 1 to 4 denials per 1000 deliveries. There is no increase in maternal or obstetrical morbidity except for a large number of out-of-hospital deliveries (30 % of complete denials) and premature deliveries (16 %, p = 0.04). Fetal morbidity appears to be higher with a rate increased of hypotrophic newborns and hospitalizations in neonatology. The woman denying her pregnancy is rather precarious and heterogeneously adheres to psychosocial support.

Denial of pregnancy seems more morbid for the child than for its mother, if we do not take into account the psychological impact of this extraordinary pregnancy.