
408 Mass. 204 (1990)
557 N.E.2d 739
ALICE BOWEN
vs.
ELI LILLY & CO., INC.
Supreme Judicial Court of Massachusetts, Worcester.
April 2, 1990.
August 6, 1990.
Present: LIACOS, C.J., WILKINS, LYNCH, O'CONNOR, & GREANEY, JJ.
John F. Keenan, for the plaintiff.
Loretta M. Smith (Marshall Simonds with her) for the defendant.
WILKINS, J.
The defendant argues that the plaintiff's negligence claim is barred because she commenced this action more than three years after her cause of action accrued. G.L.c. 260, § 2A (1988 ed.). A judge in the Superior Court agreed and allowed the defendant's motion for summary *205 judgment. We transferred the plaintiff's appeal here on our own motion and now affirm the judgment.[1]
We summarize the undisputed record facts. During her pregnancy with the plaintiff, the plaintiff's mother took the prescription drug diethylstilbestrol (DES) to prevent a threatened miscarriage. The plaintiff was born on April 14, 1948. In 1969 the plaintiff underwent an operation for a malignant vaginal tumor, during which a colostomy was performed as well as a radical hysterectomy. The complaint in this action was filed approximately fourteen years later on March 23, 1983. The question is whether, on the summary judgment record, there is a dispute of material fact as to whether the three-year statute of limitations had run before this action was commenced.[2]
This court has recognized the unfairness of a rule that holds that the statute of limitations has run even before a plaintiff knew or reasonably should have known that she may have been harmed by the conduct of another. We, therefore, have developed (in the absence of a governing statute) a discovery rule for the purpose of determining when a cause of action accrues, and thus when the statute of limitations starts to run. This rule prescribes as crucial the date when a plaintiff discovers, or any earlier date when she should reasonably *206 have discovered, that she has been harmed or may have been harmed by the defendant's conduct.
We first adopted the discovery rule in Hendrickson v. Sears, 365 Mass. 83, 83-84 (1974). There we held that, if an attorney's negligent title search overlooked an easement of record and the title defect was, in the circumstances, inherently unknowable by his clients, their cause of action against him did not accrue until they discovered or should reasonably have discovered the attorney's misrepresentation concerning the record title. Id. at 90-91. We declined to apply the rule, then applicable to medical malpractice claims, that the statutory period began to run when the negligent act occurred, even if the plaintiff could not reasonably ascertain the harm until later. Id. at 86, citing Capucci v. Barone, 266 Mass. 578, 581 (1929). Two years after the Hendrickson case, we applied the discovery rule to claims of fraudulent misrepresentations in the sale of real estate. Friedman v. Jablonski, 371 Mass. 482, 485 (1976). We recognized that, when the plaintiffs claimed a misrepresentation concerning the existence of a right of way over other property, the plaintiffs had certain obligations of reasonable inquiry and that the decision whether any misrepresentation should reasonably have been uncovered had to be made in light of what reasonable inquiry would have disclosed. Id. at 485-486. We concluded that by the time the plaintiffs took title to the property, reasonable inquiry would have shown that there was no right of way, and thus the statute of limitations began to run at that time. Id.
We extended the discovery rule to medical malpractice actions, thus overruling Capucci v. Barone, supra, in Franklin v. Albert, 381 Mass. 611, 618-619 (1980). We said that medical malpractice "causes of action accrue when the plaintiff learns, or reasonably should have learned, that he has been harmed by the defendant's conduct." Id. at 619. The principle thus stated does not require that the plaintiff know or have reason to know that the defendant violated a legal duty to the plaintiff, but only that she knew or had reason to know that she had been harmed by the defendant's conduct. *207 See White v. Peabody Constr. Co., 386 Mass. 121, 130 (1982) ("The `notice' required is not notice of every fact which must eventually be proved in support of the claim"); Fidler v. Eastman Kodak Co., 714 F.2d 192, 198-199 (1st Cir.1983) (Massachusetts law). The plaintiff need not know the full extent of the injury before the statute starts to run. Olsen v. Bell Tel. Laboratories, Inc., 388 Mass. 171, 175 (1983). The important point is that the statute of limitations starts to run when an event or events have occurred that were reasonably likely to put the plaintiff on notice that someone may have caused her injury. See Franklin v. Albert, supra at 618.
This case presents an aspect of the discovery rule with which this court has not previously been confronted. Our prior cases have focused on the question whether, in given circumstances, the plaintiff's should reasonably have discovered that they had been harmed. In each of these cases, there was no significant doubt concerning the cause of the harm once the plaintiffs discovered it. In this case, on the other hand, the plaintiff was always well aware that she had sustained substantial physical harm. The question is whether she was sufficiently on notice as to the cause of her physical harm.
Construing Massachusetts law, the Court of Appeals for the First Circuit in 1983 faced the question of the level of notice of causation a plaintiff must have to trigger the running of the statute of limitations. Fidler v. Eastman Kodak Co., 714 F.2d 192, 199 (1st Cir.1983). The Court of Appeals said: "Defining how much notice of cause is enough notice is inherently problematic where, as here, establishment of actual causation is itself an issue to be resolved at trial on the merits. If cause were defined in its strictest sense, a cause of action would never accrue for purposes of the statute until cause, when at issue, had been resolved at trial. See Dawson v. Eli Lilly Co., 543 F. Supp. 1330, 1334 (D.D.C. 1982). Such a definition would entirely defeat the purposes of a statute of limitations in this class of cases, and we know of no court which has gone so far." Id. at 198. The court concluded *208 "that under Massachusetts law notice of likely cause is ordinarily enough to start the statute running. Thus on notice, the potential litigant has the duty to discover from the legal, scientific, and medical communities whether the theory of causation is supportable and whether it supports a legal claim." Id. at 199.
The plaintiff argues that the reference to "notice of likely cause" in the quoted language means that a plaintiff must have probable cause to believe that the defendant's acts were the cause of her physical injuries before the statute begins to run. There is no Massachusetts case law in support of this view. The Court of Appeals opinion does not adopt that position. Our Appeals Court did not read the Court of Appeals opinion as the plaintiff claims when it said: "Massachusetts does not require discovery of each of the elements of the cause of action  duty, breach, causation, and damages before the limitation clock in G.L.c. 260, § 4 starts ticking.... Rather, the three-year limitations period commences to run when a reasonably prudent person (in the tort claimant's position), reacting to any suspicious circumstances of which he might have been aware (what the Court of Appeals in Fidler called `likely cause'), should have discovered that he had been harmed by his physician's treatment." (Citations and footnote omitted.) Malapanis v. Shirazi, 21 Mass. App. Ct. 378, 382-383 (1986). We do not require that a plaintiff have notice of a breach of a duty before a cause of action may accrue, but we do require that a plaintiff have (1) knowledge or sufficient notice that she was harmed and (2) knowledge or sufficient notice of what the cause of harm was.
We shall now turn to the summary judgment record to see whether a reasonable person in the position of the plaintiff would have been on notice that her mother's ingestion of DES may have caused the plaintiff's cancer. Whether in a given case there was significant notice of causation depends on the facts. We conclude that the plaintiff had such direct information bearing on the cause of her cancer that the statute of limitations ran before this action was commenced.
*209 After the 1969 operation on the plaintiff, at the request of the operating surgeon, the plaintiff and her mother met with Dr. Arthur L. Herbst, a medical researcher. Dr. Herbst asked them many questions, including questions about what medication the plaintiff's mother may have taken during pregnancy. Her mother told Dr. Herbst in the plaintiff's presence that she had taken DES. On April 15, 1971, Dr. Herbst wrote a letter to the plaintiff's mother, which the plaintiff, then twenty-three years old, read. In that letter, Dr. Herbst stated that as a result of the study of women with vaginal tumors "we have found an important association" between the ingestion of DES by pregnant women and vaginal tumors in their daughters but it was "certainly not the sole cause" of the kind of cancer the plaintiff had had.[3]
In 1971, an article by Dr. Herbst and two other physicians was published stating that there was a statistically significant association between the ingestion of DES by pregnant women and the appearance of clear cell adenocarcinoma of the vagina in a small number of their daughters.[4] The article *210 states that maternal ingestion of DES during early pregnancy "appears to have enhanced the risk of vaginal adenocarcinoma developing years later in the offspring exposed." Dr. Herbst sent a copy of the article to the plaintiff's mother in 1971, and the plaintiff read it. She knew the article was "about me."
In 1972 the plaintiff began to keep a file of magazine articles that discussed the DES controversy. Among those articles was one dated February, 1976, written by a physician and read at the time by the plaintiff, which stated that "[a]s dozens of similar cases were reported, it became clear that the culprit [i.e., the cause of the exceedingly rare vaginal cancer] was [DES]."
We conclude that, on the summary judgment record, the prospect of a significant causal connection between DES and the plaintiff's cancer was brought to the plaintiff's attention more than three years before this action was commenced. The fact it was not until June, 1982, that the plaintiff believed that DES caused her cancer does not aid her because we test the accrual of her cause of action by what a reasonable person in her position would have known or on inquiry would have discovered at the various relevant times. In this case, the plaintiff was aware not only of numerous articles published in the popular media but also she knew of scientific opinion, based in part on the plaintiff's own circumstances, stating that there was the prospect of a causal link between DES and the rare vaginal cancer from which she suffered.
Reasonable notice that a particular product or a particular act of another person may have been a cause of harm to a plaintiff creates a duty of inquiry and starts the running of the statute of limitations. On the undisputed facts, the plaintiff was on notice more than three years before this action was begun in 1983 that DES consumed by her mother may *211 have caused her cancer. The evidence shows the plaintiff's firsthand knowledge of significant information from knowledgeable sources bearing on causation.
It is true that the record does not show uncontrovertibly that the plaintiff learned more than three years before this action was commenced that the defendant was the manufacturer of the DES that her mother ingested. Evidence of the manufacturer's identity, however, had been readily available at all times through the pharmacist who sold the DES to the plaintiff's mother. It is a fact as to which the plaintiff had a duty of inquiry based on the information concerning causation that she had.
Judgment affirmed.
NOTES
[1]  A separate claim based on breach of warranty was also decided against the plaintiff in part because there was no privity of contract between the plaintiff and the defendant. At the time of the plaintiff's injuries, lack of privity was a defense to a breach of warranty claim. See Hoffman v. Howmedica, Inc., 373 Mass. 32, 34-36 (1977). The plaintiff has not appealed from that ruling.
[2]  We treat as properly part of the summary judgment record documents that the plaintiff produced in response to a court order erroneously entered and later revoked. The judge who decided the summary judgment question was asked to reconsider the question and implicitly ruled that the documents were a proper subject of a motion to produce. He was correct.

The claim, raised for the first time on appeal, that an affidavit referring to attached documents, signed by an attorney for the defendant, failed to comply with Mass. R. Civ. P. 56 (e), 365 Mass. 824 (1974), lacks merit. The attached documents were portions of deposition transcripts and documents produced by the plaintiff.
[3]  The substance of the letter states: "As I recently told you over the telephone, our study of girls with vaginal tumors has been completed. The results show that among the eight mothers of girls who developed this tumor, seven took the hormone, stilbestrol, starting early in pregnancy. It is important to realize that one mother took no hormones during pregnancy, and her daughter still developed a tumor. In summary, we have found an important association, but this is certainly not the sole cause of these tumors."
[4]  The article, published in the New England Journal of Medicine, was entitled "ADENOCARCINOMA OF THE VAGINA" and subtitled "Association of Maternal Stilbestrol Therapy with Tumor Appearance in Young Women." An abstract of the article, appearing in bold print below its heading, reads as follows: "Adenocarcinoma of the vagina in young women had been recorded rarely before the report of several cases treated at the Vincent Memorial Hospital between 1966 and 1969. The unusual occurrence of this tumor in eight patients born in New England hospitals between 1946 and 1951 led us to conduct a retrospective investigation in search of factors that might be associated with tumor appearance. Four matched controls were established for each patient: data were obtained by personal interview. Results show maternal bleeding during the current pregnancy and previous pregnancy loss were more common in the study group. Most significantly, seven of the eight mothers of patients with carcinoma had been treated with diethylstilbestrol started during the first trimester. None of the control group were so treated (p less than 0.00001). Maternal ingestion of stilbestrol during early pregnancy appears to have enhanced the risk of vaginal adenocarcinoma developing years later in the offspring exposed." Herbst, A.L., & others, ADENOCARCINOMA OF THE VAGINA, 284 New Eng. J. Medicine 878 (April 22, 1971).
