LYNCH, Circuit Judge.
This is the government’s appeal from a pre-trial order by a district court excluding from jury consideration three photographs, which the government has charged are child pornography.
In 2004, Rudy Frabizio was indicted on, inter alia, one count of possession of child pornography, in violation of 18 U.S.C. § 2252(a)(4)(B). That statute prohibits the knowing possession of:
1 or more books, magazines, periodicals, films, video tapes, or other matter which contain any visual depiction that has been mailed, or has been shipped or transported in interstate or foreign commerce, or which was produced using materials which have been mailed or so shipped or transported, by any means including by computer, if—
(i) the producing of such visual depiction involves the use of a minor engaging in sexually explicit conduct; and
(ii) such visual depiction is of such conduct....
[82]*8218 U.S.C. § 2252(a)(4)(B). “[S]exually explicit conduct” is, in turn, defined as, inter alia, “lascivious exhibition of the genitals or pubic area of any person.” Id. § 2256(2)(A)(v).1
The government’s filings state that Fra-bizio’s former employer, the Limbach Company, had found certain images on Frabizio’s work computer and had terminated Frabizio for violating company rules concerning internet usage' — in particular, rules prohibiting the viewing of inappropriate websites. FBI examiners then found a number of images on Frabizio’s work computer that formed the basis for his indictment for possession of child pornography. In response to Frabizio’s request for a bill of particulars, the government identified nineteen specific images it intended to introduce at trial.
Frabizio moved to have the district court review the nineteen images before trial and to exclude from evidence those that the court determined would not meet the legal definition of “sexually explicit conduct.”2 The government objected to the procedure, arguing that such a preliminary review of the images interfered with the jury’s function. The government also argued that the standard to be applied if the court were to engage in such a review should be whether a reasonable jury could find that an image depicts “sexually explicit conduct” within the meaning of 18 U.S.C. § 2256(2)(A).
On April 21, 2005, the district court granted Frabizio’s request that it perform a preliminary review of the images in order to determine their admissibility. The court, as the government had urged, adopted the standard of whether a reasonable jury could find that the images depicted “sexually explicit conduct” in the form of “lascivious exhibition of the genitals or pubic area.”
At the hearing before the district court, the government explained that it was prepared to present evidence that three of the images, Exhibits 1, 2, and 3, were of “known child victims.”3 This evidence was significant because “the government must prove that an image depicts actual children to sustain a ... conviction” under the statute. United States v. Hilton, 386 F.3d 13, 18 (1st Cir.2004) (per curiam) (citing Ashcroft v. Free Speech Coal, 535 U.S. 234, 251-56, 122 S.Ct. 1389, 152 L.Ed.2d 403 (2002)). Frabizio focused his challenge on those three images and one other. After examining the images, and eschewing consideration of the circumstances in which the photographs were produced or of any other evidence, the district court issued an order on May 9, 2005, in which it excluded from evidence [83]*83the three images of the putative “known child victims,” Exhibits 1, 2, and 3, but agreed with the government that the fourth challenged exhibit was admissible.
Utilizing the so-called “Dost factors,” see United States v. Dost, 636 F.Supp. 828, 832 (S.D.Cal.1986), aff'd sub nom. United States v. Wiegand, 812 F.2d 1239 (9th Cir.1987), the district court concluded that no reasonable jury could conclude that Exhibits 1, 2, or 3 met the statutory requirement of “lascivious exhibition of the genitals or pubic area.” The court then said it was excluding the images pursuant to Rule 104(a) of the Federal Rules of Evidence.4 In a footnote, the court also said it would use Rule 403 of the Federal Rules of Evidence as an alternate basis for exclusion, because the government could rely on the sixteen other images identified in its bill of particulars, and thus Exhibits 1, 2, and 3 would only be cumulative.
In this interlocutory appeal, over which we have jurisdiction pursuant to 18 U.S.C. § 3731, the government challenges the exclusion of the three images. We reverse, disagreeing both with the district court’s ultimate conclusion and with the methodology of analysis that it used.
I.
Exclusion of the Exhibits Under Fed.R.Evid. 104(a)
The question before us, as framed by the parties, is whether a reasonable jury reviewing the three photographs could have concluded that they met the statutory requirement of “lascivious exhibition of the genitals or pubic area.”5 No deference is owed to the district court’s resolution of this question. Indeed, this question, like one arising in the context of a challenge to the sufficiency of evidence supporting a jury’s verdict, is one of which we engage in de novo review. Cf. United States v. Rayl, 270 F.3d 709, 712 (8th Cir.2001) (reviewing a sufficiency challenge to a jury verdict of guilty in a child pornography case); cf. also United States v. Rivera Rangel, 396 F.3d 476, 482 (1st Cir.2005) (engaging in de novo review of sufficiency challenge); United States v. Pimental, 380 F.3d 575, 583 (1st Cir.2004) (same). Also, our review of the meaning of the statute is de novo. See In re Pharmatrak, Inc., 329 F.3d 9, 19 (1st Cir.2003); United States v. Horn, 187 F.3d 781, 789 (8th Cir.1999).
The statutory question before us must be placed in the context of the Supreme Court’s decision in New York v. Ferber, 458 U.S. 747, 102 S.Ct. 3348, 73 L.Ed.2d 1113 (1982), which upheld against a First Amendment challenge a New York statute criminalizing the distribution of child pornography. In Ferber, the Court held that the New York statute served the purpose of “prevention of sexual exploitation and abuse of children,” which was “a government objective of surpassing importance.” [84]*84Id. at 757, 102 S.Ct. 3348. The Court recognized that “the use of children as subjects of pornographic materials is harmful to the physiological, emotional, and mental health of the child[ren].” Id. at 758, 102 S.Ct. 3348. The distribution of child pornography, the Court reasoned, “is intrinsically related to the sexual abuse of children in at least two ways”: “First, the materials produced are a permanent record of the children’s participation and the harm to the child[ren] is exacerbated by their circulation. Second, the distribution network for child pornography must be closed if the production of material which requires the sexual exploitation of children is to be effectively controlled.” Id. at 759, 102 S.Ct. 3348 (footnote omitted); see also Osborne v. Ohio, 495 U.S. 103, 110-11, 110 5.Ct. 1691, 109 L.Ed.2d 98 (1990) (upholding the prohibition on private possession of child pornography for these same reasons, among others).
Because of the “particular and more compelling interest in prosecuting those who promote the sexual exploitation of children,” the Court held that all child pornography' — even that which is not obscene under the standard set forth in Miller v. California, 413 U.S. 15, 93 S.Ct. 2607, 37 L.Ed.2d 419 (1973) — is outside the scope of the First Amendment and can be banned. Ferber, 458 U.S. at 761, 102 S.Ct. 3348; see also Free Speech Coal., 535 U.S. at 240, 122 S.Ct. 1389 (“As a general rule, pornography can be banned only if obscene, but under Ferber, pornography showing minors can be proscribed whether or not the images are obscene.... ”).
Importantly for our case, the Supreme Court also held in Ferber that laws banning child pornography withstand First Amendment scrutiny so long as “the conduct to be prohibited [is] adequately defined by the applicable ... law, as written or authoritatively construed”; the material prohibited “involvefs] live performance or photographic or other visual reproduction of live performances”; and “criminal responsibility [is not] imposed without some element of scienter on the part of the defendant.” Ferber, 458 U.S. at 764-65, 102 S.Ct. 3348. The Court then looked to the New York statute, which prohibited the distribution of material depicting “sexual conduct,” which was statutorily defined as, inter alia, “lewd exhibition of the genitals.” The Court concluded this was a definition which did not offend the First Amendment. See id. at 765, 773-74, 102 S.Ct. 3348.
The Supreme Court went beyond that. It also observed that the term “lewd exhibition of the genitals” was a known quantity in this area of law, and that it “was given in Miller as an example of a permissible regulation.” Id. at 765, 102 S.Ct. 3348 (citing Miller, 413 U.S. at 25, 93 S.Ct. 2607); see also Osborne, 495 U.S. at 114, 110 S.Ct. 1691.
The language of the federal statute under consideration in this case is virtually the same as that upheld in Ferber as an adequate definition in light of First Amendment concerns.6 In 18 U.S.C. § 2256(2)(A), the word “lascivious” replaces the word “lewd,” as was used by the New York statute upheld in Ferber. Moreover, the federal prohibition extends beyond “the genitals” to the “pubic area.”7 [85]*85The Courts of Appeals have uniformly treated the terms “lewd” and “lascivious” as materially equivalent. See, e.g., United States v. Adams, 343 F.3d 1024, 1035 (9th Cir.2003) (“We hold that the statute at issue in Ferber is legally indistinguishable from 18 U.S.C. § 2256(2)(A).... [T]his court has equated ‘lascivious’ with ‘lewd.’ ” (citing Wiegand, 812 F.2d at 1243)); United States v. Reedy, 845 F.2d 239, 241 (10th Cir.1988). The Supreme Court has itself endorsed this position. See United States v. X-Citement Video, Inc. (X-Citement Video II), 513 U.S. 64, 78-79, 115 S.Ct. 464, 130 L.Ed.2d 372 (1994) (approving of United States v. X-Citement Video, Inc., 982 F.2d 1285, 1288 (9th Cir.1992), rev’d on other grounds, X-Citement Video II, 513 U.S. 64, 115 S.Ct. 464, 130 L.Ed.2d 372). The addition of the term “pubic area” has independent significance in that it broadens the class of exhibitions that may be .prohibited.
“Lascivious” is a “commonsensical term,” and whether a given depiction is lascivious is a question of fact for the jury. Wiegand, 812 F.2d at 1243; see also Rayl, 270 F.3d at 714 (“[T]he question whether materials depict ‘lascivious exhibition of the genitals,’ an element of the crime, is for the finder of fact.”); Reedy, 845 F.2d at 241 (“This [cjourt agrees ... that ‘lascivious’ is ... a commonsensical term .... ” (internal quotation mark omitted) (quoting Wiegand, 812 F.2d at 1243)). Indeed, “[tjhere is a consensus among the courts that whether the item to be judged is lewd, lascivious, or obscene is a determination that lay persons can and should make.”8 United States v. Arvin, 900 F.2d 1385, 1390 (9th Cir.1990); see also id. (citing cases). The courts are also in agreement that the term “lascivious” is sufficiently well defined to provide persons “of reasonable intelligence, guided by common understanding and practices,” notice of what is permissible and what is impermissible. United States v. Freeman, 808 F.2d 1290, 1292 (8th Cir.1987) (rejecting vagueness challenge); accord, e.g., X-Citement Video II, 513 U.S. at 78-79, 115 S.Ct. 464 (endorsing circuit court’s conclusion that “lascivious” was a constitutionally permissible standard and was neither overbroad nor vague); Adams, 343 F.3d at 1035-36 (rejecting argument that “lascivious” is “too subjective” and “not susceptible to a common understanding”); cf. Ferber, 458 U.S. at 765, 102 S.Ct. 3348 (holding that the New York statute was not unconstitutionally underinclusive, because it “sufficiently describes a category of material the production and distribution of which is not entitled to First Amendment protection”).
Subject to motions under Rule 29 of the Federal Rules of Criminal Procedure, it is up to the jury to determine whether the images identified in the bill of particulars as a basis for an indictment under 18 U.S.C. § 2252(a)(4)(B) constitute visual depictions of “sexually explicit conduct,” defined as “lascivious exhibition of the genitals or pubic area” under 18 U.S.C. § 2256(2)(A)(v). In making this determination, the standard to be applied by the jury is the statutory standard. The statutory standard needs no adornment. The Supreme Court has made clear that the [86]*86Constitution does not require additional glossing or narrowing of the standard, see Ferber, 458 U.S. at 765, 102 S.Ct. 3348; cf. id. at 764, 102 S.Ct. 3348 (“A trier of fact need not find that the material appeals to the prurient interest of the average person; it is not required that sexual conduct portrayed be done so in a patently offensive manner; and the material at issue need not be considered as a whole.”), and Congress has chosen not to employ any additional glossing. Further definitional guides are not required and, indeed, would be prohibited if they functioned to narrow the statutory definition.9
Using the statutory standard and asking whether a reasonable jury could conclude that Exhibits 1, 2, and 3 met the standard, this panel has reviewed the disputed images and has concluded that a reasonable jury could decide that the three photographs constitute lascivious exhibitions of the genitals or pubic area within the meaning of the statute.
We describe how a reasonable jury could view the three exhibits under consideration, with full recognition that a thousand words are not necessarily worth a picture. Each of the three photographs depicts a nude girl, who is posed alone and who is looking directly at the camera. Each girl appears on the cusp of puberty, either prepubescent or adolescent. The subjects of the photographs, who are of an age when girls normally are clothed even when in nature or in a stream, are completely unclothed (except for some jewelry), and the settings of the photographs provide no ready explanation that makes the nudity indisputably innocent. Moreover, in each photograph, a jury could reasonably conclude that there was an “exhibition” of the “pubic area”: each of the girls’ legs are parted and the pubic area is plainly visible. Indeed, the photos could reasonably be seen as focusing on or particularly drawing attention to the girls’ pubic areas and, specifically, to their vaginas. A jury could reasonably conclude that none of the girls’ postures were natural or spontaneous, that each girl was deliberately posed to exhibit her pubic area, and that the posture in which each was posed was not a comfortable one. As a jury will consider the images, we think the wisest course is to avoid more detailed description of them.
In light of the criteria under the statute and the constitutional limits set by Ferber, and our own review of the exhibits, we conclude that a reasonable jury could find that the three photographs constitute “lascivious exhibitions of the genitals or pubic area” within the meaning of the statute, and that the district court erred in taking the evidence away from the jury.
II.
Difficulties with the Analytical Methodology and the Use of the Dost Factors
Having held that the district court erred in its determination, under Rule 104(a), that no reasonable jury could find these images to be a lascivious display of the genitals or pubic area, we also express [87]*87concern about the approach that the district court took in reaching its decision— an approach that, we recognize, was urged upon the court by the parties. In excluding the three exhibits, the court analyzed the question of whether to exclude the evidence almost exclusively in terms of the Dost factors, and, in our view, overemphasized those factors in a way which raised the risk of inappropriately limiting the statute.
This court has described the Dost factors as follows:
(1) whether the genitals or pubic area are the focal point of the image; (2) whether the setting of the image is sexually suggestive (i.e., a location generally associated with sexual activity); (3) whether the child is depicted in an unnatural pose or inappropriate attire considering her age; (4) whether the child is fully or partially clothed, or nude; (5) whether the image suggests sexual coyness or willingness to engage in sexual activity; and (6) whether the image is intended or designed to elicit a sexual response in the viewer.
United States v. Amirault, 173 F.3d 28, 31 (1st Cir.1999) (citing Dost, 636 F.Supp. at 832).
In Amirault, this court gave a qualified endorsement of the Dost factors, stating that they are “generally relevant and provide some guidance.” Id. at 32. We did not, however, suggest that the Dost factors were the equivalent of — or established the limits of — the statutory term “lascivious.” Indeed, we reached the opposite eonclusion: “[w]e emphasize[d] ... that these factors are neither comprehensive nor necessarily applicable in every situation” and that “[t]he inquiry will always be case-specific.” Id.; see also United States v. Hilton, 257 F.3d 50, 57 (1st Cir.2001) (warning that the Dost factors, “although ‘generally relevant,’ are not eomprehen-sive[,] and each determination of whether an image contains a lascivious display is necessarily case specific” (quoting Amirault, 173 F.3d at 32)).
In this case, the district court’s analysis, although reciting the above language, in fact gave the Dost factors greater weight than warranted. The court appeared to treat the Dost factors as exhaustive and to use them to set the boundaries of the statutory term “lascivious.” The court thus applied the six Dost factors in a way that accorded to them the same status as the statutory definition itself.
The consequence of the district court’s unqualified application of the Dost factors was to take the issue of the lasciviousness of the three images away from a jury. None of the cases in which this court has referred to the Dost factors raised such a prospect.10 In Amirault, for example, the issue on appeal was whether the district court had properly increased the sentence, under the U.S. Sentencing Guidelines, of a defendant who had pleaded guilty to one count of possession of child pornography, by applying a cross-reference that resulted in a higher base-offense level if the crime involved trafficking in visual depictions of lascivious exhibition of the genitals or pubic area of a minor. 173 F.3d at 30-31. [88]*88In Amirautt, the task of interpreting and applying the Sentencing Guidelines was for the court, and any close “judgment calls” — and we noted that there were some — were the court’s to make. Id. at 35. Indeed, the particular image on which the trafficking cross-reference was predicated was not one that had formed the basis of the conviction. Id. at 30.
No other circuit court, as best we can tell, has ever approved the use of the Dost factors in a pretrial proceeding to remove the consideration of the lasciviousness of an image from a jury.11
There are many reasons for the need for caution about the use of the Dost factors, particularly in this way. First is the fact that the Dost factors have fostered myriad disputes that have led courts far afield from the statutory language. One dispute is, for example, how many of the factors must be present in an image for it to qualify as “lascivious.”12 Compare, e.g., United States v. Wolf, 890 F.2d 241, 245 & n. 6 (10th Cir.1989) (“We do not hold that more than one Dost factor must be present .... ”), with United States v. Villard, 885 F.2d 117, 122 (3d Cir.1989) (“Although more than one factor must be present in order to establish ‘lasciviousness,’ all six factors need not be present.”). Another dispute is about what the specific factors mean. See, e.g., Amirault, 173 F.3d at 34 (cataloging disagreement about what the sixth Dost factor means). As one commentator observed, “the Dost test has produced a profoundly incoherent body of case law.” A. Adler, Inverting the First Amendment, 149 U. Pa. L.Rev. 921, 953 (2001). There is every reason to avoid importing unnecessary interpretive conundrums into a statute, especially where the statute employs terms that lay people are perfectly capable of understanding.
Even more significantly, there is a risk that the Dost factors will be used to inappropriately limit the scope of the statutory definition.13 That is impermissible. We offer two examples in which such a risk has been raised.
The first example is one that was noted by the Ninth Circuit when affirming one of the convictions in the Dost case. In United States v. Wiegand, 812 F.2d 1239, the Ninth Circuit noted that the Dost factors were “over-generous to the defendant.” Id. at 1244. Specifically, the court took issue with the fifth factor articulated by the district court: “whether the visual depiction suggests sexual coyness or a willingness to engage in sexual activity.” Dost, 636 F.Supp. at 832. The appellate court expressed disapproval at “[t]he standard employed by the district court[, which] ... implied] ... that the pictures would not be lascivious unless they showed [89]*89sexual activity or willingness to engage in it.” Wiegand, 812 F.2d at 1244. Emphasizing that “[t]he offense defined by the statute is depiction of a ‘lascivious exhibition of the genitals,’ ” the appellate court held that it was enough that “the pictures were an exhibition,” “[t]he exhibition was of the genitals,” and “[e]ach of the pictures featured the child photographed as a sexual object.” Id.
It is obvious that if an image does depict a sexually alluring look from the minor, it will be easier to show that the image is lascivious. The absence of a sexual come-on, though, does not mean that an image is not lascivious, as Wiegand and other cases have noted. See, e.g., United States v. Knox, 32 F.3d 733, 747 (3d Cir.1994) (“Children posing for pornographic pictures may suffer dramatic harm regardless of whether they have an ‘adult’ look of sexual invitation or coyness on their face.”); Wolf, 890 F.2d at 247 (noting that “a sexually exploitative photograph of a child need not portray the victim in a pose that ‘depicts lust, wantonness, sexual coyness or other inappropriate precocity’ ”). Children do not characteristically have countenances inviting sexual activity, and the statute does not presume that they do. By suggesting that the child subject must exhibit sexual coyness in order for an image to be lascivious, the district court in Dost ran the risk of limiting the statute.
A second example of how the Dost factors may risk limiting the statute manifested itself in this case. In its order, the district court overread Amirault as holding that a jury, in determining whether a given image constitutes a “lascivious exhibition of the genitals or pubic area,” is limited to considering “the objective criteria of the photograph’s design,” Amirault, 173 F.3d at 35 — what the district court called “the four corners of the image”— and nothing else.14 The district court erred in stating that this court has adopted a general “four corners rule.” Amirault did not adopt such a rule,15 and the text of the statute itself does not require it.
The issue of the four corners rule, and even of what it means, has not been decided by this circuit, and we do not decide it here. The issue is complicated, and there are arguments going different ways. For example, it is clear that the jury may hear evidence about the circumstances of the production of an image in determining [90]*90whether the child depicted therein is real. It is arguable that a jury should not be precluded from considering such evidence on the question of lasciviousness as well. The laws prohibiting possession of child pornography are constitutional because the government has a compelling interest in preventing sexual exploitation of children; it is not obvious that a jury cannot consider evidence of exactly that exploitation in evaluating the lasciviousness of the materials. Cf. Free Speech Coal., 535 U.S. at 254, 122 S.Ct. 1389 (“In the case of the material covered by Ferber, the creation of the speech is itself the crime of child abuse .... ”); see also id. at 250, 122 S.Ct. 1389 (noting that “speech [that] had what the Court in effect held was a proximate link to the crime from which it came” was not constitutionally protected). But there are also arguments, usually made in the context of the very different question of whether the subjective reaction or intent of the viewer should be taken into account when determining whether an image is lascivious, that lasciviousness should be determined from the image alone. Cf. Villard, 885 F.2d at 125 (holding, in the context of a sufficiency-of-the-evidence challenge to a jury verdict, that in evaluating the question of an image’s lasciviousness, “[w]e must ... look at the photograph, rather than the viewer,” because if “we were to conclude that the photographs were lascivious merely because Villard found them sexually arousing, we would be engaging in conclusory bootstrapping”).
The issue, however, has not been squarely presented to us in this case.16 We flag it only to express concern that in deriving such a prohibition from Dost or from a misunderstanding of our case law, the district court ran the risk of impermis-sibly narrowing the scope of the statute by imposing upon the statute a limitation that was in no way compelled by the statutory text itself.
We stress that our holding today is limited: We do not hold that the Dost factors may never be used. We hold only that they are not the equivalent of the statutory standard of “lascivious exhibition” and are not to be used to limit the statutory standard.17
III.
Exclusion of Exhibits Under Fed.R.Evid. 403
In a footnote, the district court alternatively excluded the three exhibits pursuant to Fed.R.Evid. 403, holding that the three images were cumulative in that the government could rely on the sixteen other images identified in its bill of particulars.
Although Rule 403 “enables a trial judge to exclude needlessly cumulative evidence,” it also “requires a balance of probative value against the negative consequences of using a particular piece of evidence.” Sec’y of Labor v. DeSisto, 929 F.2d 789, 794-95 (1st Cir.1991). We review the district court’s application of Rule 403 deferentially, but will overturn the district court’s ruling if there is an abuse of discretion. United States v. Gilbert, 229 F.3d 15, 20-21 (1st Cir.2000). [91]*91“[A]n abuse of discretion occurs ‘when a relevant factor deserving of significant weight is overlooked, or when an improper factor is accorded significant weight, or when the court considers the appropriate mix of factors, but commits a palpable error of judgment in calibrating the deci-sional scales.’ ” Id. at 21 (quoting United States v. Roberts, 978 F.2d 17, 21 (1st Cir.1992)).
Here, the district court abused its discretion by failing, as required by Rule 403, to properly weigh its concerns about cumulativeness against the probative value of the evidence. In fact, the court did not even comment directly on the probative value of the three exhibits; it merely quoted the conclusion of the district court in United States v. Dean, 135 F.Supp.2d 207 (D.Me.2001), that the “four nonessential, questionable photos [in that case were] not particularly probative.” Id. at 211. The three images at issue in this case were the only ones for which the government was prepared to introduce evidence that the girls depicted therein were known child victims; to satisfy its burden to show that the sixteen other images were of real minors, the government would have to call on experts to testify.
Having failed to undertake properly the balancing required by Rule 403, the district court abused its discretion in excluding the images under that rule.
IV.
We reverse the district court’s exclusion of the three images; we hold they are admissible in evidence. The case is remanded for further proceedings consistent with this opinion.