delivered the opinion of the court:
The common issue in these consolidated appeals is whether the plaintiffs’ actions arising from medical treatment are barred by the four-year repose period prescribed by statute for bringing such actions. Under that provision, no action concerning medical treatment may be brought against a hospital more than four years after the time of the occurrence on which the cause of action is based. (See Ill. Rev. Stat. 1983, ch. 110, par. 13 — 212.) The four-year repose provision went into effect on September 19, 1976; in both cases here the treatment occurred more than four years before the effective date of the new period and the actions were filed more than four years after that date.
The history of each case may be stated briefly. In cause No. 60027 the plaintiff, Dominic Mega, filed his complaint in the circuit court of Cook County on September 24, 1982. The action arose from a series of X rays administered to the plaintiff at Holy Cross Hospital for several months in 1949 for treatment of an enlarged thymus gland. The plaintiff alleged that as a result of the X-ray treatment tumors developed on his thymus gland, a condition that he discovered in March 1981. The defendant moved to dismiss the complaint as barred by the four-year period of repose, and the trial judge granted the motion. The appellate court reversed that judgment (122 Ill. App. 3d 720), and we allowed the defendant’s petition for leave to appeal (94 Ill. 2d R. 315(a)).
In cause No. 60038 the plaintiff, Michael M. Sieman, filed his action in the circuit court of Cook County on December 8, 1981. The plaintiff alleged that from 1947 through 1954 he underwent a series of X-ray treatments for tonsillitis at Holy Cross Hospital and that as a result of that treatment tumors developed on his thyroid gland, a condition that he discovered on January 8, 1980. Although Sieman’s condition was discovered less than four years after the effective date of the statutory amendment imposing the four-year repose period, the action was filed more than four years after the effective date, and therefore the defendant moved to dismiss the action as untimely; the trial judge granted the motion. The appellate court reversed that judgment (122 Ill. App. 3d 1159 (order under Supreme Court Rule 23 (87 Ill. 2d R. 23))), and we allowed the defendant’s petition for leave to appeal (94 Ill. 2d R. 315(a)). In this court the two appeals were consolidated on motion of the defendant.
When plaintiff Sieman brought his action in December 1981, section 21.1 of the Limitations Act (Ill. Rev. Stat. 1979, ch. 83, par. 22.1) provided in pertinent part:
“No action for damages for injury or death against any physician or hospital duly licensed under the laws of this State, whether based upon tort, or breach of contract, or otherwise, arising out of patient care shall be brought more than 2 years after the date on which the claimant knew, or through the use of reasonable diligence should have known, or received notice in writing of the existence of the injury or death for which damages are sought in the action, whichever of such date occurs first, but in no event shall such action be brought more than k years after the date on which occurred the act or omission or occurrence alleged in such action to have been the cause of such injury or death.” (Emphasis added.)
By the time plaintiff Mega commenced his action in September 1982, section 21.1 had been recodified as section 13 — 212 of the Code of Civil Procedure and also had been amended (Ill. Rev. Stat., 1982 Supp., ch. 110, par. 13 — 212), but the two provisions were identical in all respects relevant here.
Under the general rule, in the wake of a statute shortening a limitations period or providing one where one did not exist previously, a plaintiff whose cause of action arose before that date will be allowed a reasonable period of time in which to bring his action. (Hupp v. Gray (1978), 73 Ill. 2d 78; Meegan v. Village of Tinley Park (1972), 52 Ill. 2d 354; Trustees of Schools v. Batdorf (1955), 6 Ill. 2d 486.) Therefore, if under the new statute a reasonable time remains, the new period can be applied, without more; if a reasonable time would not remain, then one will be allowed. In both cases here the appellate court believed that the reasonable period to which the plaintiffs were entitled could exceed the length of the repose period itself, four years, and the causes were remanded for a determination of whether the actions were timely. Notably, in two other cases involving the four-year repose provision, the appellate court has reached the opposite conclusion. (See Clark v. St. John’s Hospital (1984), 128 Ill. App. 3d 989; Roberson v. Taylor (1983), 115 Ill. App. 3d 587.) In Clark and Roberson the appellate court held that actions based on acts occurring before the four-year repose provision took effect but commenced more than four years after that date must be considered untimely, and the same result is urged here by the defendant. We agree.
In Moore v. Jackson Park Hospital (1983), 95 Ill. 2d 223, this court considered the application of the four-year repose provision to causes of actions based on acts occurring before the provision went into effect. Moore was a consolidation of three separate actions. In each case suit was commenced within two years of the alleged discovery of the cause of action and within the four-year period of time following September 19, 1976, the effective date of the amendment providing the four-year repose period. The causes of action were based on acts that occurred more than four years before that date, however, and therefore the amendment left no time in which the plaintiffs could commence their actions. In each case the circuit court dismissed the actions as automatically barred by the repose provision. Consistent with the general rule regarding the effect of shortened limitations periods, the court in Moore held that the 1976 provision would not operate as an instantaneous bar and that the plaintiffs were entitled to a reasonable period of time, following the effective date of the provision, in which to bring their actions. Accordingly, the causes there were remanded for a determination of whether the actions had been filed within a reasonable period of time.
As in Moore, the acts involved here occurred more than four years before the effective date of the 1976 amendment, which left no time in which to file the actions; like the plaintiffs in Moore, then, the plaintiffs here were entitled to á reasonable period of time following that date in which to bring their actions. Unlike the plaintiffs in Moore, however, the plaintiffs here did not file their actions until more than four years after the four-year repose provision took effect. We conclude that the reasonable time to which the plaintiffs here were entitled did not extend beyond that provided by the new repose period, computed from its effective date, September 19, 1976. Therefore, the actions must be considered untimely. (See Orlicki v. McCarthy (1954), 4 Ill. 2d 342.) To allow, as a reasonable time for bringing suit, a period greater than the repose period itself would defeat the purpose of the statute. For the plaintiffs here, then, the reasonable period could have ended no later than four years following the effective date of the 1976 amendment. Because the plaintiffs’ actions were filed after that time, they must be considered barred.
We realize that our holding here means that plaintiff Mega’s action was barred before he learned of his injury. That is the effect of the four-year period of repose provided by the 1976 amendment, however, and it will affect acts occurring after September 19, 1976, in the same way that it operates here. The period of repose gives effect to a policy different from that advanced by a period of limitations; it is intended to terminate the possibility of liability after a defined period of time, regardless of a potential plaintiff’s lack of knowledge of his cause of action. (See Gates Rubber Co. v. USM Corp. (7th Cir. 1975), 508 F.2d 603, 611-12 (discussing the separate purposes advanced by “bifurcated” statutes of limitations).) Plaintiff Sieman raises several constitutional objections to this operation of the statute, though his own injury was discovered within four years of the effective date of the 1976 amendment. Plaintiff Mega has been affected in that way, however, and though he has not raised those objections, perhaps because of this court’s decisions in Moore v. Jackson Park Hospital (1983), 95 Ill. 2d 223, and Anderson v. Wagner (1979), 79 Ill. 2d 295, we shall consider the problem here. Sieman argues that barring a cause of action before it is discovered violates principles of due process as well as the provisions in the Illinois Constitution ensuring the existence of a remedy for every wrong and prohibiting the impairment of contracts' (Ill. Const. 1970, art. I, secs. 2, 12, 16; U.S. Const., amend. XIV).
In Anderson this court reviewed, for the first time, the four-year repose provision and in a comprehensive opinion held that it was constitutional. In reaching that conclusion, the court in Anderson recognized that the repose provision could have the effect of barring a cause of action before its discovery. (79 Ill. 2d 295, 311-12.) The constitutionality of the provision seemingly was reaffirmed in Moore. Without reexamining the reasoning of those decisions, we shall address one suggested constitutional basis for the discovery rule. We note that a variety of repose provisions have been found to be invalid under other States’ constitutions. (See, e.g., Kenyon v. Hammer (1984), 142 Ariz. 69, 688 P.2d 961; Daugaard v. Baltic Cooperative Building Supply Association (S.D. 1984), 349 N.W.2d 419.) The provision’s validity depends here, however, on the Illinois Constitution, and not on the constitution of another State.
The discovery rule is not required by the “certain remedy” provision of the Illinois Constitution (Ill. Const. 1970, art. I, sec. 12). The corresponding provision in the previous constitution (see Ill. Const. 1870, art. II, sec. 19) was interpreted as “an expression of a philosophy and not a mandate that a ‘certain remedy’ be provided in any specific form or that the nature of the proof necessary to the award of a judgment or decree continue without modification” (Sullivan v. Midlothian Park District (1972), 51 Ill. 2d 274, 277), and that interpretation has been given to the current provision as well (People v. Dowery (1975), 62 Ill. 2d 200, 207-08; see Pierce v. Board of Education (1977), 69 Ill. 2d 89, 92-93). Although the “certain remedy” provision has been held to prohibit the abolition by the legislature of a particular cause of action (Heck v. Schupp (1946), 394 Ill. 296 (holding unconstitutional a statute barring civil actions based on alienation of affections, criminal conversation, and breach of promise to marry)), it has not been held to prohibit statutes that restrict the amount or type of damages recoverable (Siegall v. Solomon (1960), 19 Ill. 2d 145; Smith v. Hill (1958), 12 Ill. 2d 588) or that require proof of wilful and wanton misconduct rather than simple negligence (Sullivan v. Midlothian Park District (1972), 51 Ill. 2d 274, 277-78; Clarke v. Storchak (1943), 384 Ill. 564).
The repose provision at issue here does not have the drastic effect prohibited by Heck. It restricts the time within which an action must be brought, but it does not eliminate an entire category or type of action. That the repose provision may, in a particular instance, bar an action before it is discovered is an accidental rather than necessary consequence. Moreover, various circumstances may ameliorate its operation. The repose provision now is expressly subject to section 13 — 215 of the Code of Civil Procedure (Ill. Rev. Stat. 1983, ch. 110, par. 13— 215), which extends the time in which to bring a cause of action if the cause has been fraudulently concealed. Also, principles of equitable estoppel may prevent a defendant from invoking the four-year repose period as a bar. Witherell v. Weimer (1981), 85 Ill. 2d 146.
Notably, the “certain remedy” provision has not played a role in the development of the discovery rule in the decisions of this court. Application of the discovery rule in Illinois, a recent phenomenon, has depended primarily on “balancing the increase in difficulty of proof which accompanies the passage of time against the hardship to the plaintiff who neither knows nor should have known of the existence of his right to sue” (Rozny v. Marnul (1969), 43 Ill. 2d 54, 70). The balance described in Rozny, which involved a surveyor’s error, has been struck as well in other fields in determining the application of the discovery rule. (See, e.g., Nolan v. Johns-Manville Asbestos (1981), 85 Ill. 2d 161, 167-68 (products liability); Tom Olesker’s Exciting World of Fashion, Inc. v. Dun & Bradstreet, Inc. (1975), 61 Ill. 2d 129, 133 (defamation).) In Williams v. Brown Manufacturing Co. (1970), 45 Ill. 2d 418, 432, in a discussion of the discovery rule, the court said, “As pointed out in Rozny v. Marnul (1969), 43 Ill. 2d 54, the constitutionally established policy of providing a remedy for every wrong inflicted is tempered by the policy of the statute of limitations which bars actions brought after the period of time which the legislature has determined makes the problems of proof so difficult as to pose a danger of injustice.” The philosophy expressed in the “certain remedy” provision is similarly tempered by the legislature’s choice of a period of repose.
As Anderson recounted, until 1965 the limitations period that governed all actions for medical malpractice was the two-year period for personal injuries. (Anderson v. Wagner (1979), 79 Ill. 2d 295, 306-07; see Ill. Rev. Stat. 1963, ch. 83, par. 15; Mosby v. Michael Reese Hospital (1964), 49 Ill. App. 2d 336.) In Mosby, an action for medical malpractice, the appellate court refused to apply the discovery rule in conjunction with the two-year period. The cause of action there arose from the failure to remove a surgical needle following an operation on the plaintiff; the action was commenced within two years of the discovery of the needle but almost six years after the surgery. The court held that the action was barred and, in the absence of express approval by the legislature, refused to apply the discovery rule to an action for medical malpractice.
Legislative approval came a year later, in 1965, when section 21.1 of the Limitations Act (Ill. Rev. Stat. 1965, ch. 83, par. 22.1) took effect. Addressing the situation involved in Mosby, section 21.1 provided that in an action based on the negligent failure to remove a foreign substance, other than flesh, blood, or bone, introduced into the body in the course of treatment or operation, the period of limitations did not begin to run until the plaintiff knew or should have known of the injury; the statute also provided an outside limit of 10 years, measured from the treatment or operation, for bringing the action.
In 1970 application of the discovery rule to cases of medical malpractice was broadened considerably by this court’s decision in Lipsey v. Michael Reese Hospital (1970), 46 Ill. 2d 32. The basis for the cause of action there was the failure to diagnose a malignant tumor; the action was filed more than three years after the misdiagnosis but within less than a year of the plaintiff’s discovery of the mistake. The court held that the action was not barred by the two-year period for bringing actions for personal injuries (see Ill. Rev. Stat. 1969, ch. 83, par. 15). Rather, the court held that “in medical malpractice cases as this, the cause of action accrues when the person injured learns of his injury or should reasonably have learned of it.” (46 Ill. 2d 32, 40.) The court did not believe that by enacting section 21.1 the legislature had intended to limit application of the discovery rule, in the area of medical malpractice, to the narrow category of cases falling within the scope of that statute. The court considered that application of the discovery rule was appropriate in the absence of the expression of a contrary intent by the legislature. 46 Ill. 2d 32, 39.
There matters stood until 1975, when section 21.1 was amended to provide that an action for medical malpractice could be brought within two years of its discovery but not later than five years of the occurrence; the provision in that section regarding foreign substances was left intact (see Ill. Rev. Stat. 1975, ch. 83, par. 22.1) . Thus, the legislature codified the rule in Lipsey but restricted its operation by imposing a five-year period of repose. These amendments were part of an attempt by the legislature to address the crisis in medical malpractice. Certain aspects of that program later were declared unconstitutional in Wright v. Central Du Page Hospital Association (1976), 63 Ill. 2d 313; the amendments to section 21.1 were not at issue there.
Section 21.1 was amended again in 1976. The legislature shortened the repose period to four years and deleted the separate provision regarding foreign substances (see Ill. Rev. Stat., 1976 Supp., ch. 83, par. 22.1) . The four-year repose provision has been a part of the statute since that time. In later amendments, the statute was expressly made subject to the separate provision regarding fraudulent concealment, and dentists and registered nurses were added to its scope. See Ill. Rev. Stat. 1983, ch. 110, par. 13—212; Ill. Rev. Stat., 1982 Supp., ch. 110, par. 13—212; Ill. Rev. Stat. 1981, ch. 83, par. 22.1.
In Illinois, then, the history of the discovery rule in the area of medical malpractice has been directed and shaped largely by the legislature. A repose period of one length or another has always limited application of the discovery rule in cases involving foreign objects, from its initial application in 1965. The discovery rule was not applied to other forms of medical malpractice until 1970, and in those cases was without restriction only until 1975, when a five-year repose period was added to section 21.1; the next year that was shortened to four years. The repose periods reflect the legislature’s balancing of an individual’s interest in recovery against the problems and costs perceived in medical malpractice actions and the public’s interest in having available to it affordable health care (see Anderson v. Wagner (1979), 79 Ill. 2d 295; Wright v. Central Du Page Hospital Association (1976), 63 Ill. 2d 313).
The discovery rule may be applied by the court in the absence of the expression of a contrary intent by the legislature. (Lipsey v. Michael Reese Hospital (1970), 46 Ill. 2d 32; Mosby v. Michael Reese Hospital (1964), 49 Ill. App. 2d 336.) That a contrary intent has been expressed here is apparent in the repose period itself. A later contrary intent was implicit in the amendment expressly providing an exception to the repose period in cases involving fraudulent concealment of the cause of the action; general application of the discovery rule would render the exception meaningless (see Gates Rubber Co. v. USM Corp. (7th Cir. 1975), 508 F.2d 603, 612). Our limited role in these circumstances was noted and defined in People ex rel. Difanis v. Barr (1980), 83 Ill. 2d 191, 201, where the court said:
“It should be emphasized that it is not the province of this court to pass on the wisdom or desirability of legislation. (Garcia v. Tully (1978), 72 Ill. 2d 1, 10.) As long as the means chosen by the legislature to achieve a desired end are lawful and inoffensive to the State and Federal constitutions, our inquiry may proceed no further.”
Having determined that the repose provision is constitutional (see Moore v. Jackson Park Hospital (1983), 95 Ill. 2d 223; Anderson v. Wagner (1979), 79 Ill. 2d 295), we conclude that the plaintiffs’ actions were barred by the period of repose.
For the reasons stated, we reverse- the judgments of the appellate court and affirm the judgments of the circuit court.
Appellate court reversed; circuit court affirmed.
"WARD and SIMON, JJ., took no part in the consideration or decision of this case.