Pascal Rossignol / Reuters Candles are displayed in front of the house where the bodies of newborn babies were found in Villers-au-Tertre, France, on July 29, 2010 
 
 The question is as horrifying as it is important to ask: Why are a rising number of French women killing their newborn babies? Finding the answer has become a matter of urgency following the discovery on Wednesday of eight infants allegedly smothered to death and buried by their mother in northern France. And with that case marking at least the fifth instance of multiple infanticide reported in France since 2003, it has become vital for the nation to confront the phenomenon that appears to be behind it all: a mental condition known as pregnancy denial. 
 
 This latest case of newborn murder in France was uncovered in the northern town of Villiers-au-Tertre, after eight tiny bodies were found buried in the gardens of two separate homes. Six of the cadavers were unearthed on July 29 by police at the house of Dominique Cottrez, 45, and her husband Pierre-Marie, 47. Investigators searched their home after the resident of a house previously owned by Dominique's parents turned up two tiny bodies on July 24 while digging a pool in the backyard. According to the French prosecutor leading the inquiry in the town, a short distance south of Lille, Dominique has admitted to hiding her pregnancies  and the killings of her babies  from her husband, whom police describe as being "dumbstruck" by the revelations. Dominique was charged for the murders; Pierre-Marie has been cleared of wrongdoing and released but could yet become a subject of investigation. (See the top 10 crime stories of 2009.) 
 
 The case in Villiers-au-Tertre is only the most recent example of a father of slain babies being apparently unaware of his wife's pregnancies. Four other such cases since 2003 include that of Véronique Courjault, 42, who was convicted in June 2009 of killing three of her newborns  two of whom she hid in a freezer and were later discovered by her husband. And this past March, Céline Lesage, 38, was found guilty of murdering six of her babies after she hid her pregnancies from the men who had fathered them. Both women were sentenced to prison  Courjault for eight years and Lesage for 15. 
 
 Experts explained those cases as resulting from pregnancy denial, an often misunderstood and minimized condition. According to Michel Delcroix, a former gynecologist who served as a court expert in the Courjault trial and others involving pregnancy issues, pregnancy denial is a quasi-schizophrenic condition in which women either don't realize or cannot accept that they are with child  not even enough to have an abortion. Whether these women are afflicted with the condition before they deliver or as they're suddenly giving birth, Delcroix explains, the psychological denial is so strong that they refuse to believe they're pregnant even when the reality confronts them. (See more on pregnancy.) 
 
 "These women are so convinced pregnancy is impossible that once the child they never wanted arrives, they don't accept it as real and get rid of it to restore order to what they believe is nonpregnant reality," Delcroix says. "However terrible its consequences, pregnancy denial acts in infanticide cases much as a psychotic state that drives someone to kill another person does. Yet we still try women for what they do during pregnancy denial when we don't try psychotic killers deemed not responsible for their actions." Delcroix and others who are fighting for pregnancy denial to be medically and legally recognized as an illness argue that improving ways to identify and treat these women makes more sense than simply punishing the crimes they commit as a result of it. 
 
 What causes the condition? Several things, Delcroix says, including previous trauma such as beatings and rape. But other, nonphysical factors can also be involved, and denial can kick in even if a woman has already had and raised children without a problem  Lesage has a 14-year-old son; Dominique Cottrez has two grown daughters. And while pregnancy denial has been around for decades or longer, Delcroix says it's rising in frequency. The probable reason, he says, is changes in wider social factors that have downgraded the value of childhood, parenting and family. 
 
 But in some cases, it can also be a matter of women simply failing to see themselves as mothers. "Some women never manage to update their self-identity during pregnancy, [while others] want to become pregnant without wanting to procreate," psychiatrist Pierre Lamothe told Le Parisien on Thursday. "When the child arrives, it doesn't really exist for them. They don't give it life, in psychological terms. If they saw it as a [real] baby, they wouldn't kill it." (See the top 25 crimes of the past century.) 
 
 Others just never realize  or acknowledge  that they're with child. Experts on pregnancy denial say most sufferers are either sufficiently overweight or experience such little body change that they simply assume they've gained some weight. In France, 230 women a year discover their pregnancy only while giving birth. Though just a fraction resort to infanticide, Delcroix fears there are more of those cases that remain undiscovered than there are ones that come to light, as in Villiers-au-Tertre. And he poses a chilling question: Does anyone really believe that the spreading phenomenon of pregnancy denial  and the infanticide it can lead to  is purely a French problem? ||||| Although infanticide occurs everywhere and at all levels of society, France seems to have been especially afflicted in the past three decades. 
 
 The most notorious case in recent years is that of Vï¿½ronique Courjault, now 41, jailed in Tours last year after admitting murdering three babies and keeping their bodies in the family freezer. 
 
 In November 1984, Jean-Pierre Leymarie and his wife Rolande were jailed for killing seven newborns in Corrèze. Four years later, Rosita Garnier, 38, was jailed by a court in Blois for murdering three newborns. 
 
 Sylvie Coulon, 27, from Limoges, was jailed in 1990 for killing four infants and putting their bodies out with the rubbish. And Cï¿½line Lesage, 34, admitted the murder of seven babies found in a cellar in Normandy in 2007. 
 
 "It's easy to come up with a narrative to explain why it happens in contemporary India or 17th-century Europe, for example, but why is it happening in 21st-century France?" asks Michelle Oberman, author of When Mothers Kill. 
 
 The recent French cases also deviate sharply from the pattern in the US, she said, where the mother is usually very young, not in a relationship and who conceals the pregnancy from her parents, and then kills the child as soon as it is born. 
 
 One of the conditions often offered up to explain infanticide is "pregnancy denial", a psychiatric condition where a woman either doesn't realise or cannot accept she's having a baby, not even enough to consider an abortion. 
 
 "Women can carry on menstruating, they don't put on weight and their breasts don't get bigger because the denial is so strong it overcomes the physical manifestations of pregnancy," explained Anne Carpenter, a consultant forensic clinical psychologist in Glasgow. When the baby arrives, she is forced to confront that reality, and sometimes with catastrophic results. 
 
 "With no sense of the child as an individual being, it is viewed more as an inconvenience, and something to be got rid of in the same way as you get rid of the trash," she added. 
 
 But denial is not the only explanation. Pierre Lamothe, a French psychiatrist, said in many cases he had studied, the women wanted to be pregnant because it made them feel fully feminine, but they did not want children. "When the child appears, it has no real existence," he said. "Mentally, the woman does not accept that it is a living person."
– It's a good question. Why, asks Bruce Crumley in TIME, are French women killing their babies? It may have something to do with a little known, "quasi-schizophrenic" phenomenon called "pregnancy denial," he finds. Women with this condition "either don't realize or cannot accept that they are with child," a doctor says. And, he adds, it's not a French-only thing. Women can become "so convinced pregnancy is impossible that once the child they never wanted arrives, they don't accept it as real and get rid of it," the doctor says. Or, as one psychologist tells the Independent, for some women a baby "is viewed more as an inconvenience, and something to be got rid of in the same way as you get rid of the trash."