The defendant, Defabian Shannon, pleaded guilty in 1995 to being a felon in possession of a firearm, in violation of 18 U.S.C. § 922(g)(1). He was sentenced to 115 months in prison, and challenges the sentence on several grounds. The panel before which his appeal was argued found merit in only one of his challenges, 94 F.3d 1065 (7th Cir.1996), and we reject the others on the basis of the panel’s opinion. By a vote of 2 to 1, the panel held that the district judge had erred in enhancing the defendant’s base offense level because of a previous conviction for sexual assault, which the judge classified as a crime of violence. We decided to rehear the case en banc in order to consider the important question of the circumstances in *384which a sexual offense against a minor not involving the use of force is nevertheless a crime of violence within the meaning of the sentencing guidelines.
The normal base offense level for the crime of being a felon in possession of a firearm is 14, but if the defendant has a “prior felony conviction of ... a crime of violence,” the base offense level rises to 20. See U.S.S.G. §§ 2K2.1(a)(4)(A), (6). The guidelines define a crime of violence as a state or federal offense punishable by imprisonment for more than a year that either “(i) has as an element the use, attempted use, or threatened use of physical force against the person of another, or (ii) is burglary of a dwelling, arson, or extortion, involves use of explosives, or otherwise involves conduct that presents a serious potential risk of physical injury to another.” U.S.S.G. § 4B1.2(1).
In 1992 Shannon had been charged with second-degree sexual assault of a child, a felony under Wisconsin law committed by anyone who “has sexual contact or sexual intercourse with a person who has not attained the age of 16.” Wis.Stat. § 948.02(2). The criminal complaint alleged facts that if believed showed that Shannon had committed a forcible rape. But the information filed against him omitted all these facts except the name and the date of birth of the girl and that he had indeed had sexual intercourse (not mere “sexual contact”) with her. Shannon was permitted to plead guilty to the information, which means that he admitted only the facts contained in it — intercourse with a girl who we know from the date of birth in the information was 13 years 10 months old at the time of the act. Shannon was 17 years 10 months old when the crime was committed and 19 when he was sentenced to three years in prison for the offense. The maximum sentence for second-degree sexual assault in Wisconsin is 10 years.
Forcible rape is of course a crime of violence, so that if we were permitted to peek behind the information and credit the allegations in the complaint we could affirm the sentence without difficulty. But this course is not open to us. There has never been a judicial finding that the sexual act that Shannon perpetrated upon the 13 year old was forcible rape. The use of force is not an element of second-degree sexual assault, so no finding on the question was necessary for conviction. Nor was there a finding of forcible rape when Shannon was sentenced for sexual assault — on the contrary, the judge said at the sentencing hearing that “you haven’t pled to a crime here that requires ... use of force or anything like that.” In his federal criminal proceeding Shannon has vigorously contested the allegation of forcible rape and has offered to present evidence that it is false. An evidentiary hearing would be necessary to determine the nature of the rape.
The district judge refused to hold such a hearing. He considered himself bound by the principle, recognized in most circuits including our own, that the characterization of a previous conviction offered to enhance the defendant’s federal sentence is to be based on the facts charged in the indictment (or, as here, the information), without a deeper inquiry into the circumstances of the offense. E.g, United States v. Lee, 22 F.3d 736 (7th Cir.1994); United States v. Palmer, 68 F.3d 52 (2d Cir.1995). We are not disposed to abandon this principle, which is contained in the guideline commentary itself, U.S.S.G. § 4B1.2(1), Application Note 2, and which is necessary to avoid greatly complicating sentencing hearings with little offsetting gain. We have deviated from this principle only when it was otherwise impossible to determine the proper classification of the offense under the sentencing guidelines and — a critical condition not satisfied here — the deviation did not require a hearing to resolve contested factual issues. United States v. Sebero, 45 F.3d 1075, 1078 (7th Cir.1995); see also United States v. Spell, 44 F.3d 936, 939 (11th Cir.1995); United States v. Smith, 10 F.3d 724, 733-34 (10th Cir.1993).
It is true that an evidentiary hearing on a defendant’s previous conduct is often a part of the sentencing process under the guidelines. We need look no further than the present ease; the district judge further increased the sentence after a hearing in which he found that Shannon had committed a murder for which he had not been charged. But in dealing with uncharged conduct there is no *385charging document on which the judge can rely; an evidentiary hearing is unavoidable. Allowing the parties to go behind a charging document could result in an evidentiary hearing in most federal sentencing proceedings— not merely in those in which previous uncharged conduct is brought in to enhance the sentence — because most federal criminal defendants have a criminal record and consideration of that record is a mandatory part of sentencing under the guidelines.
Current uncharged conduct, it is true, is typically rather than just occasionally involved in federal sentencing, because the charge is typically limited to a subset of the defendant’s criminal conduct that gave rise to the charge — for example, an ounce of cocaine when he’s actually sold a kilo. See U.S.S.G. § 1B1.3 (relevant conduct). But criminal history deals with old, not current, conduct. If the district judge were required to go behind the charging document to determine the defendant’s criminal history, the eviden-tiary burden of exploring the circumstances of old crimes would potentially be borne in every ease in which the defendant had a criminal history. It would be a heavy burden not only because of the frequency with which it would have to be borne but also because of the unusual evidentiary difficulties and uncertainties involved in exploring criminal conduct that may have occurred many years ago and in jurisdictions remote from that of the current sentencing. It is not surprising that the guidelines direct the judge, in computing a defendant’s criminal history, to give primary attention to his previous convictions. See U.S.S.G. § 4A1.1.
Of course, just as with the uncharged murder, the judge could have based an upward departure on the uncharged forcible rape. U.S.S.G. § 4A1.3(e); United States v. Ruffin, 997 F.2d 343 (7th Cir.1993). But upward departures are exceptional; enhancement on the basis of the defendant’s criminal history is automatic. (And under section 4Al.l(f), a prior sentence for a crime of violence is one of the grounds for a mandatory enhancement.) Limiting judicial inquiry in the computation of the defendant’s criminal history to the formal charging document thus saves the district judge considerable time in the majority of cases.
The criminal complaint that touched off the sexual-assault proceeding against Shannon might be thought a charging document. The critical difference between it and the information, however, is that the information was the basis of the conviction and sentence and all its allegations were admitted and must be deemed established, while the complaint contains factual allegations that are contested and would require an evidentiary hearing to confirm. We are told that in some states the criminal complaint may be the only charging document. When that is so, the judge might have to determine disputed facts alleged in it, although probably the better alternative, by analogy to the doctrine of collateral estoppel, would be for the judge to consider only the minimum facts required to support the conviction — the facts that must have been found (or admitted) in the earlier proceeding.
Confined as we are to the information, we must decide whether sexual intercourse, not shown or conceded to be forcible, with a 13 year old is a crime of violence within the meaning of the guidelines, an issue of federal law even though the crime is one defined by state law. United States v. Phipps, 68 F.3d 159, 161 (7th Cir.1995). The government argues that any felonious sexual act with a minor should be deemed either to involve force, because the minor is incapable of giving legally recognized consent, or to involve conduct that presents a serious risk of physical injury. (A “risk” is by definition probable not certain, hence potential rather than actual; “potential risk” appears to be a redundancy in the guideline.) An inference of violence from mere unconsented-to physical contact, the government’s first reason for arguing that every felonious sexual act with a minor is per se a crime of violence, would not wash in this circuit. It would transform any uneonsented-to touching that the law has made a felony into a crime of violence, including picking a person’s pocket, a crime that we have held is not a crime of violence, United States v. Lee, supra, 22 F.3d at 740-41; Lowe v. United States, 923 F.2d 528, 530 (7th Cir.1991); see also United States v. *386Mathis, 963 F.2d 399, 406-10 (D.C.Cir.1992), though some courts disagree with us on this. E.g., United States v. Mobley, 40 F.3d 688, 696 (4th Cir.1994); United States v. McVicar, 907 F.2d 1 (1st Cir.1990).
As for ruling that any felonious sexual act with a minor creates a “serious potential risk of physical injury,” this suggestion was undermined at oral argument when the government’s lawyer conceded that the goals behind laws forbidding sex with minors are various and need not include the goal of protecting the minor from a serious risk of physical injury. This concession implies, correctly in our view, that these laws must be considered one by one to see whether the conduct punished by the particular law under which the defendant was convicted involves a serious risk of physical injury. In some states, such as Illinois, it is a felony to have sex with a person under the age of 18 (under 17 if there are no aggravating factors, such as a substantial discrepancy in ages). 720 ILCS 5/12-15, 5/12-16. Yet persons can marry in Illinois at the age of 16 with parental approval. 750 ILCS 5/203. It is unlikely therefore that the age of consent in the Illinois statute was chosen with the purpose in mind of protecting minors from the physical consequences of sex. We cannot be certain about this because the requirement of surrogate consent by the minor’s parents might be thought adequate to protect those teenagers for whom sex might be physically injurious whether because of medical conditions or sheer immaturity that would make pregnancy at once unlikely to be averted by contraception and physically hazardous to mother or fetus. But the point is only that a concern with physical injury cannot be read off automatically from a statute punishing sex with minors.
Another reason for this conclusion is the wide variance in the age above which sex with a minor is not made felonious in the absence of any aggravating factors. In Iowa, for example, the minor need only have reached the age of 14, Iowa Stat. § 702.5, and in Pennsylvania she need only have turned 13. Pa.CSA 18 § 3121(6). The U.S. population is biologically homogeneous; if sex does not create a serious risk of physical injury to a 13 year old in Pennsylvania, it does not create a serious such risk to a 13 year old in Illinois. The states with very low ages of consent are in a distinct minority. They may simply be wrong in their assessment of the risks; they may be less averse to risk than other states; they may be less child-protective; or they may consider felony statutes an inapt instrument for regulating teenage sex. No inference can be drawn that these states consider sex with a 13 year old or a 14 year old to be harmless to the girl or that if they do they are right. Our point is only, once again, that a serious risk of physical injury cannot be automatically inferred from the existence of a statutory-rape law. To make the answer to the question whether felonious sex with a minor is a crime of violence a mechanical function of the laws of the different states would be arbitrary because it would make distinctions unsupportable on the basis of the risk of physical injury, that risk being a constant across states and the only relevant criterion (once the use of force is set to one side) in the guideline; would undermine the guidelines’ goal of bringing about a reasonable uniformity in federal sentencing; and would treat “crime of violence” as á question of state rather than federal law.
Some eases from other circuits might be read as taking the approach suggested by the government and thus deeming any felonious sex act with a minor a per se crime of violence. Most of them can be distinguished, however, as involving a prepubeseent child, incest, or other aggravating factors and in none, so far as appears from the court’s factual recitation, was the minor at the top of the relevant age range with no aggravating factor present. See United States v. Velazquez-Overa, 100 F.3d 418, 422 (5th Cir.1996); United States v. Taylor, 98 F.3d 768, 774 (3d Cir.1996); United States v. Bauer, 990 F.2d 373 (8th Cir.1993) (per curiam); United States v. Rodriguez, 979 F.2d 138 (8th Cir.1992); United States v. Wood, 52 F.3d 272 (9th Cir.1995); United States v. Reyes-Castro, 13 F.3d 377 (10th Cir.1993); United States v. Passi, 62 F.3d 1278, 1282 (10th Cir.1995); Ramsey v. INS, 55 F.3d 580 (11th Cir.1995) (per curiam).
*387A modification of the government’s suggested approach would be for the sentencing judge to decide whether the particular state’s statutory-rape law that the defendant had violated was based on a concern with the risk of physical injury and if it was to classify any violation of that law as a crime of violence. Wisconsin has made 16 the age below which sexual activity with a minor is felonious. The likelihood of physical injury as a consequence of sex is greater with a 15 year old than with a 17 year old. The younger child is likely to have poorer judgment, less knowledge about sex, and less money, all of which deficits will make it less likely that she will use or insist that her partner use effective measures to prevent pregnancy and disease. She is also less likely to be a responsible expectant mother, so there is danger to her fetus. These are grounds for thinking that the Wisconsin statute may be concerned with risk of serious injury after all, but against this it can be argued that the fixing of a lower age of consent than 16 by a number of states is evidence that the danger to a 15 year old of physical injury from sex is not great. Wisconsin’s second-degree sexual-assault statute, moreover, is not limited to sexual intercourse; it includes sexual contact, which can be as noninvasive as fondling a breast or buttock through clothing for the purpose of arousing the fondler sexually. Wis.Stat. § 948.01(5)(a). Such contact might disturb a young person, but it would be highly unlikely to cause physical injury. From the fact that the statute seems to equate mere sexual contact to sexual intercourse it could be argued that the animating concern is not with physical injury incident to sex.
A further complication, so far as characterizing the purpose behind a particular state’s statutory-rape law is concerned, lies in the origins of these laws. Their original purpose was to protect the virginity of female minors in order, in turn, to protect their marriageability, viewed as a girl’s or a woman’s most precious asset and one gravely impaired by loss of virginity. Comment, “Adolescents in Jeopardy: An Analysis of Texas’ Promiscuity Defense for Sexual Assault,” 29 Houston L.Rev. 583, 586-87 (1992); Michelle Ober-man, “Turning Girls Into Women: Re-evaluating Modem Statutory Rape Law,” 5 J.Crim.L. & Criminology 15, 26 (1994). Only recently has the focus of governmental concern with teenage sex shifted to the protection of young girls from pregnancy, sexually transmitted diseases, possible psychological harms incident to early commencement of sexual activity, and possible adverse social and economic consequences of teenage pregnancy and births out of wedlock. The extraordinary variety of state statutory-rape laws and the well-known failure of state legislatures to keep their sex laws up to date with the changing sexual mores of the American people make it difficult to impute a single goal to statutory-rape laws, let alone a goal centering on the risk of physical injury.
To decide this case, however, we need not characterize the goals or grounds of the Wisconsin statute or for that matter of any other specific law punishing sex with minors. All that the crime of violence guideline requires is that the defendant’s offense “involves” a serious potential risk of physical injury, United States v. Wood, supra, 52 F.3d at 276, not that that risk be the concern that animates the statute creating the offense. And it is common ground between the parties that in deciding just what the defendant’s offense was we are free to look at the facts charged in the indictment or information; we are not confined to the minimum conduct that would create the offense. (The issue discussed earlier was whether we can go deeper into the facts, not whether we can go that far.) Those facts are that the defendant had sexual intercourse, not just sexual contact, with a 13 year old, not a 15 year old. The Wisconsin statute covers a lot of ground, and some of it may not be crime of violence ground. But sexual intercourse with a 13 year old is in our view a crime of violence within the meaning of the guidelines, because it does present a serious risk of physical injury. A 13 year old is unlikely to have a full appreciation of the disease and fertility risks of intercourse, an accurate knowledge of contraceptive and disease-preventive measures, and the maturity to make a rational comparison of the costs and benefits of premarital intercourse. See, e.g., Mark A. Schuster et al., “Communication Between Adolescents and Physicians About Sexual Be*388havior and Risk Prevention,” 150 Archives of Pediatrics & Adolescent Medicine 906 (1996); Linda A. Webster, Stuart A. Berman & Joel R. Greenspan, “Surveillance for Gonorrhea and Primary and Secondary Syphilis Among Adolescents, United States — 1981-1991,” 42 Morbidity & Mortality Wkly.Rep. No. SS-3, p. 1 (Aug. 13, 1993). Furthermore, a very young girl who becomes pregnant is quite likely not to take good care of herself and her fetus, and so the pregnancy will be more dangerous to both than if she were older. For this reason and possibly for biological reasons as well, the pregnancy of a 13 year old is considered a high-risk pregnancy — and the risk is a risk of physical injury to the mother as well as to the fetus or baby. See, e.g., Alison M. Fraser, John E. Broeker & R.H. Ward, “Association of Young Maternal Age With Adverse Reproductive Outcome,” 332 N.Eng.J.Med. 1113 (1995); Nelson W. Davidson & Marianne E. Felice, “Adolescent Pregnancy,” in Comprehensive Adolescent Health Care 1026, 1035-36 (Stanford B. Friedman, Martin Fisher & S. Kenneth Schonberg eds. 1992).
The medical complications of pregnancy are plainly a form of physical injury. What about the pregnancy itself? Pregnancy resulting from rape is routinely considered a form of grave bodily injury. E.g., United States v. Yankton, 986 F.2d 1225, 1230 (8th Cir.1993); Fenelon v. State, 629 So.2d 955, 956 (Fla.App.1993); People v. Sargent, 86 Cal.App.3d 148, 150 Cal.Rptr. 113 (1978). Apart from the nontrivial discomfort of being pregnant (morning sickness, fatigue, edema, back pain, weight gain, etc.), giving birth is intensely painful; and when the pregnancy is involuntary and undesired, the discomfort and pain have no redemptive features and so stand forth as a form of genuine and serious physical injury, just as in the ease of an undesired surgical procedure (a pertinent example being involuntary sterilization). Most surgical procedures cause discomfort and pain; we bear these by-products to cure or avert a greater injury or illness; when there is no greater injury or illness to avert, the by-products become pure injury. No one doubts that a person who is operated on by mistake can recover damages for the pain and suffering inflicted by the operation, which he could not do if he had consented to it.
To the extent that a 13 year old is incapable of appreciating the full risk and consequences of sexual intercourse, her ensuing pregnancy and parturition (or abortion) must be considered at least quasi-involuntary and could well be considered, therefore, a physical injury even if the pregnancy is normal. And sex with a 13 year old creates a significant risk of pregnancy. Indeed, the risk appears to have materialized here. Shannon’s victim became pregnant, she believes as the result of the statutory rape, and gave birth. By the age of 19, when Shannon was sentenced for that rape, he had fathered five children, of whom a second also appears to be the product of a statutory rape. The pregnancy of a 13 year old is arguably a physical injury in itself and clearly creates a substantial risk of secondary physical injury to mother or fetus from complications of the pregnancy (there is no information in the presentence investigation report, from which the facts about Shannon’s having fathered children are taken, about the health of the child of his 13 year old victim); and the guideline does not grade physical injury by gravity.
It is true that the only class of sex offenses to which the guideline commentary refers in a list of examples of crimes of violence is “forcible sex offenses.” All forcible sex offenses are crimes of violence; it does not follow that no nonforcible ones are. Many states still criminalize fornication and adultery; these adult nonforcible sex offenses could not plausibly be thought crimes of violence. It does not follow that sexual intercourse with a 13 year old is not a crime of violence. The guideline itself lists burglary of a home, arson, extortion, and crimes involving the use of explosives as crimes that create a serious risk of personal injury. Arson and especially crimes involving explosives may be more dangerous to physical safety than a 13 year old’s having intercourse; but burglary and extortion may be less dangerous. Most burglars take pains to avoid an encounter with the occupant of the burgled dwelling, see, e.g., United States v. King, 62 F.3d 891, 896 (7th Cir.1995), and *389much extortion involves blackmail or trolling for bribes rather than any threat, let alone actuality, of violence — yet all extortion is classified as a “crime of violence.” United States v. DeLuca, 17 F.3d 6, 10 (1st Cir.1994). The examples given in the guideline thus suggest a liberal test for serious risk of personal injury (as we have held in classifying attempted burglary as a crime of violence, United States v. Sandies, 80 F.3d 1145, 1150 (7th Cir.1996); United States v. Davis, 16 F.3d 212 (7th Cir.1994)), and it is a test that intercourse with a 13 year old passes.
We are mindful that statutory rape is more often thought of as a “morals offense” than as a “crime of violence”; and it might well be doubted whether being guilty of a morals offense would make one a more dangerous possessor of a firearm than a person who had never committed such an offense. But neither the lay classification of statutory rape nor our opinion concerning the soundness of the penological judgment that the commission of such an offense should result in a punishment bonus for a felon in possession of a firearm is relevant to our decision. By defining crime of violence (so far as relevant here) as a crime that “involves conduct that presents a serious potential risk of physical injury to another,” the Sentencing Commission made the term one of art, superseding its lay meaning. And by making classification turn entirely on the risk of physical injury, the Commission withdrew from the courts discretion to base enhancement of the punishment of a felon in possession on a judgment of the soundness, as a matter of penological theory or policy, of basing such an enhancement on a particular type of crime. Judicial sentencing discretion is not extinguished, but it is confined to the decision whether to depart upward or downward from the sentence computed in accordance with the guidelines.
Shannon’s lawyer asks us to limit “crime of violence” to those sex offenses (other than rape) that involve incest or prepubescent children (pedophilia). These are crimes of peculiar horror in our society. But the only added risk of physical injury in cases of incest is the risk of deformed offspring should pregnancy ensue, and while sex with a prepubescent child involves a greater risk of physical injury to the child’s sexual organs if there is penetration, it creates no pregnancy risk; and much, perhaps most, pedophilia does not involve penetration. So Shannon’s suggested test is arbitrary. We need not adopt a comprehensive test. It is enough that any reasonable test would classify sexual intercourse with a 13 year old as conduct that creates a serious risk of physical injury and hence as a crime of violence within the meaning that the sentencing guidelines give the term.
From the length of this opinion and the contrary judgment of the panel majority, it should be apparent that the interpretive issue is a difficult one. We cannot be certain that we have gotten it right. The difference in punishment between level 14 and level 20 can, depending on the defendant’s criminal history, be great. For example, for a defendant in Criminal History Category IV, the difference is between a sentencing range of 27 to 33 months and one of 51 to 63 months. U.S.S.G. ch. 5, pt. A (Sentencing Table). So it is important that the issue be resolved correctly. We urge the Sentencing Commission to clarify the crime of violence guideline — more particularly as our decision leaves unresolved the proper treatment of cases in which the victim of the statutory rape is above the age of 13.
Affirmed.