Villard-Mackintosh L, & Vessey, M. (1993). Oral contraceptives and reproductive factors in multiple sclerosis incidence. Contraception, 47(2), 161-168. https://doi.org/10.1016/0010-7824(93)90088-o
Villard-Mackintosh L, Vessey M. Oral contraceptives and reproductive factors in multiple sclerosis incidence. Contraception. 1993;47(2):161-168. doi:10.1016/0010-7824(93)90088-o
Villard-Mackintosh L, and Martin Vessey. "Oral contraceptives and reproductive factors in multiple sclerosis incidence." Contraception, vol. 47, no. 2, 1993, pp. 161-168.
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Department of Public Health and Primary Care, Radcliffe Infirmary, Oxford, England.
Linked to ROR, the Research Organization Registry
Abstract
Data from the Oxford.FPA prospective study show that oral contraceptive use and pregnancy have no discernible effect on the risk of developing multiple sclerosis (MS). Women of parity 0-2 developed MS twice as often as women of parity 3 or more but the difference did not reach statistical significance. Smoking may be a risk factor for developing MS. A nested case-control analysis did not identify any associations between MS onset and preceding illnesses.
There is good evidence that estrogens and progestogens have an important effect on bone metabolism. This article explores the relationship between oral contraceptive (OC) use and fractures occurring at various sites among the 17,032 participants in the Oxford-Family Planning Association contraceptive study, which now includes information accumulated during 310,000 woman-years of observation between 1968 and 1994. In total, 1308 women suffered at least one fracture during the follow-up period, which was largely confined to premenopausal years. When all fractures were combined, there was a modest, but highly significant trend (p < 0.001) of increasing risk with total duration of oral contraceptive use. In addition, there was statistically significant heterogeneity (p < 0.01) when overall fracture rates were examined in relation to recency of oral contraceptive use during the premenopausal lifespan. The highest relative risk (1.3, 95% CI 1.1-1.5) was for current or recent oral contraceptive users; however, viewed as a whole, no clear pattern of risk was apparent. Examination of the data for individual fracture sites (including the lower end of the radius/ulna) did not provide any evidence of a protective effect of oral contraceptive use. These results are closely similar to those reported from the Royal College of General Practitioners Oral Contraception Study in 1993. Estrogens and progestogens have an important effect on bone metabolism. The present study explored the relationship between oral contraceptive (OC) use and bone fractures in the cohort of 17,032 English and Scottish participants in the Oxford-Family Planning Association contraceptive study (1968-94). The analysis was based on the calculation of woman-years of observation terminated by referral for fracture or release from follow-up due to death, emigration, or short-term pill users reaching age 45 years. A total of 1308 women experienced at least one fracture during 310,000 woman-years of observation and there was a significant (p 0.001) positive relationship between age and fracture risk. Most common were fractures of the radius/ulna, tarsal/metatarsal bones, and ankle. When all fractures were combined, there was a significant (p 0.001) increasing risk with total duration of OC use. Also observed was a significant (p 0.01) heterogeneity when overall fracture rates were examined in relation to recency of OC use during the premenopausal lifespan. The highest relative risk (1.3; 95% confidence interval, 1.1-1.5) was recorded among current or recent OC users. There was about a 20% increase in the overall risk of fracture in women who had used OCs at any time compared with never-users. Overall, however, no clear pattern of risk emerged. These results are similar to those reported in the 1993 Royal College of General Practitioners OC Study. It is assumed that the increased fracture risk in OC users results from life-style characteristics of such women rather than a direct effect of OCs on bone.
World Health Organization Collaborative Study of Cardiovascular Disease and Steroid Hormone Contarception, 1995·Lancet
The composition and use of oral contraceptives (OCs) have changed since their cardiovascular side-effects were established 20 years ago. This report describes the risk of idiopathic venous thromboembolic (VTE) events (deep vein thrombosis [DVT] and/or pulmonary embolism [PE]) in association with current use of combined OCs among 1143 cases aged 20-44 and 2998 age-matched controls, as evaluated in a hospital-based, case-control study in 21 centres in Africa, Asia, Europe, and Latin America. OC use was associated with an increased risk of VTE in Europe (odds ratio 4.15 [95% CI 3.09-5.57]) and in non-European ("developing") countries (3.25 [2.59-4.08]). Risk estimates were generally higher for DVT than for PE but no consistent trend by certainty of diagnosis (definite, probable, possible) was found. Increased risk was apparent within 4 months of starting OCs, was unaffected by duration of current episode of OC use, and had disappeared within 3 months of stopping OCs. Relative risk estimates of VTE associated with OC use were unaffected by age of user, by history of hypertension (excluding hypertension in pregnancy), or in any consistent way by smoking. However, in both groups of countries increased body mass index (BMI) was an independent risk factor for VTE, and OC-associated odds ratios were higher among those with a BMI above 25 kg/m2 than among those with smaller BMIs. OC-associated risk estimates were high among women in Europe with a history of hypertension in pregnancy. Odds ratios associated with the use of OCs containing a third-generation progestagen were higher than those observed with progestagens of the first (norethindrone type) and second (norgestrel group) generation. Odds ratios associated with first and second generation progestagens tended to be lower, though not significantly, when used in combination with low (< 50 micrograms oestrogen) rather than higher oestrogen doses. This study confirms an association between OC use and VTE in Europe and the developing countries, although overall risk estimates associated with use were lower than demonstrated in most previous studies of non-fatal idiopathic VTE.
Gut and Inflammatory Bowel Disease · Inflammatory Bowel Disease
Vessey M et al., 1986·Br Med J (Clin Res Ed)·Free full text on PubMed Central
Since the start in 1968 of the Oxford Family Planning Association contraceptive study 31 women have developed ulcerative colitis and 18 have developed Crohn's disease, giving incidences of 0.15 and 0.09/1000 woman years respectively. The incidence of ulcerative colitis in women who were non-smokers on entry to the study was 0.17/1000 woman years and the incidence in smokers was 0.11/1000 woman years. The findings for Crohn's disease were entirely different, the corresponding incidences being 0.05 and 0.17/1000 woman years respectively. Both ulcerative colitis and Crohn's disease were more common among women currently using oral contraceptives than among those not doing so. Incidences per 1000 woman years for ulcerative colitis were 0.26 in users and 0.11 in non-users; for Crohn's disease the incidences were 0.13 and 0.07 respectively. Though the association between the use of oral contraceptives and chronic inflammatory bowel disease cannot be regarded as established, the effects of smoking have been shown consistently in many studies. This observation provides an important clue to the aetiology of chronic inflammatory bowel disease.
Comparative Studies · Contraception Versus Fertility Awareness
Summary In 1968, a prospective study was started in collaboration with the Family Planning Association to try to provide a balanced view of the beneficial and harmful effects of different methods of contraception. This investigation is now in progress at seventeen clinics and over 17,000 women are under observation. At the time of recruitment, all these women were married white British subjects, aged 25–39 years, who voluntarily agreed to participate. Fifty-six per cent were using oral contraceptives, 25% were using a diaphragm and 19% were using an intrauterine device (IUD). During follow-up each woman is questioned at return visits to the clinic and a record of pregnancies and their outcome, hospital referrals (inpatient or outpatient), changes in contraceptive methods and the results of cervical smears, is accumulated. Women who default are sent a postal questionnaire and, if this is not returned, are telephoned or visited in their homes to collect the necessary information. So far, data obtained during 56,000 woman-years of observation are available for analysis. Follow-up has been maintained with an annual lapse rate of about 0.3%due to withdrawal of co-operation or loss of contact; adherence to the method of contraception in use at recruitment has been reasonably good, and the reporting of pregnancies and hospital admissions appears to have been both reliable and unbiased. The present data include only 24 deaths, so the mortality associated with different contraceptive methods cannot yet be estimated. With regard to morbidity, however, our preliminary results closely resemble those obtained in the prospective study carried out by the Royal College of General Practitioners (1974) and in the principal retrospective studies carried out in Britain and the United States. Women who used oral contraceptives at the start of the study experienced a deficiency of hospital referrals for cancer, benign lesions of the breast, menstrual disorders other than amenorrhoea, duodenal ulcer, and retention cysts of the ovary; they showed an excess of referrals for cerebrovascular disease, cervical erosion, skin disorders, self-poisoning, migraine, venous thrombosis and embolism, hayfever, gallbladder disease, amenorrhoea, and sterility. Women who used a diaphragm showed a deficiency of hospital referrals for carcinoma-in-situ and dysplastic lesions of the cervix uteri and accidental injury; and an excess of referrals for haemorrhoids and cystitis. Women who used an IUD experienced an excess of hospital referrals for anaemia, varicose veins and salpingitis. About half of these differences (12 out of 23) were predicted from other studies while some suggestive evidence already existed for a further five. Of the remaining six, some probably reflect the influence of selective factors or chance. Multiple pregnancies, stillbirths, malformations, the sex ratio and birthweight showed no consistent relationship to method of contraception. The outcome of unplanned pregnancies occurring in women using an IUD, however, was remarkably unfavourable both in terms of ectopic gestation and miscarriage. Clear evidence was found of impairment of fertility after discontinuation of oral contraceptives. Whether this is likely to lead to permanent sterility in some women is uncertain. The study has provided data on the efficacy of a wide variety of contraceptive methods. In general the failure rates are in keeping with those obtained in other large-scale studies, save that those for the diaphragm and the sheath are much lower than those usually quoted. The available evidence does not yet allow a final balance to be struck between the benefits and risks associated with the new methods of contraception that have become widely used during the last two decades. It seems clear, however, that there are no material risks associated with the use of the diaphragm apart from the risk of pregnancy and that there may be some unintended benefits.
Experimental and clinical data suggest a protective effect of estrogens on the development and progression of MS. We assessed whether MS incidence was associated with oral contraceptive use or parity in two cohort studies of U.S. women, the Nurses' Health Study (NHS; 121,700 women aged 30 to 55 years at baseline in 1976) and the Nurses' Health Study II (NHS II; 116,671 women aged 25 to 42 years at baseline in 1989). Participants with a diagnosis of MS before baseline were excluded. Oral contraceptive history and parity were assessed at baseline and updated biennially. During follow-ups of 18 years (NHS) and 8 years (NHS II) we documented a total of 315 definite or probable cases of MS. Neither use of oral contraceptives nor parity were significantly associated with the risk of MS. As compared with women who never used oral contraceptives, the age-adjusted relative risk (95% CI) was 1.2 (0.9, 1.5) for past users, and 1.0 (0.6, 1.7) for current users. Similar results were obtained after adjustment for latitude, ancestry, and other potential confounding factors. There was no clear trend of MS risk with either increasing duration of use or time elapsed since last use. Age at first birth was also not associated with the risk of MS. These prospective results do not support a lasting protective effect of oral contraceptive use or pregnancy on the risk of MS. The decision to use hormonal contraception should not be affected by its effects on the risk of MS.
Exogenous estrogens affect the onset and clinical course of experimental allergic encephalomyelitis. Oral contraceptives, a frequent source of exogenous estrogens in humans, could have a role in the development of multiple sclerosis (MS). To examine whether recent oral contraceptive use and pregnancy history are associated with the risk of MS. DESIGN AND A case-control study nested in the General Practice Research Database. This database contains prospective health information (drug prescriptions and clinical diagnoses) on more than 3 million Britons who are enrolled with selected general practitioners. One hundred six female incident cases of MS, younger than 50 years, with at least 3 years of continuous recording in the General Practice Research Database before the date of first symptoms (index date), identified between January 1, 1993, and December 31, 2000, and 1001 controls matched on age, practice, and date of joining the practice. Main Outcome Measure Incidence of first symptoms of MS, confirmed through medical records. The incidence of MS was 40% lower (odds ratio, 0.6; 95% confidence interval, 0.4-1.0) in oral contraceptive users compared with nonusers during the previous 3 years. The risk of MS increased in the 6 months after pregnancy (odds ratio, 2.9, 95% confidence interval, 1.2-6.6), but it was not otherwise related to parity. The hormonal changes that occur during oral contraceptive use and pregnancy may be associated with a short-term reduction in the risk of MS, and the postpartum period may be associated with a short-term increase in the risk of MS.
To examine the risk of multiple sclerosis in users of combined oral contraceptives.
Cohort study conducted between 1968 and 1996 using diagnostic data supplied by general practitioners General practices throughout the United Kingdom. Royal College of General Practitioners' Oral Contraception Study cohort of initially 46,000 women recruited during the late 1960s. Directly standardised incidence rates of multiple sclerosis were calculated for current, former and never-users of oral contraceptives using first ever cases of multiple sclerosis reported by the general practitioners. The standardisation variables were age, parity, social class and smoking history. Five-year survival rates in the different contraceptive groups were calculated using standard life table techniques. One hundred and fourteen first ever cases of multiple sclerosis had been reported by November 1996 during 564,000 woman-years of observation. The incidence rate in both current and former users was not materially different to that in never-users. Although based on limited evidence there was no suggestion that the five-year survival was affected by a woman's use of combined oral contraceptives. These findings do not suggest a greatly elevated risk of multiple sclerosis during, or after, use of combined oral contraceptives.
Hellwig K et al., 2016·PLoS One·Free full text on PubMed Central
The incidence of multiple sclerosis (MS) is rising in women. To determine whether the use of combined oral contraceptives (COCs) are associated with MS risk and whether this varies by progestin content. We conducted a nested case-control study of females ages 14-48 years with incident MS or clinically isolated syndrome (CIS) 2008-2011 from the membership of Kaiser Permanente Southern California. Controls were matched on age, race/ethnicity and membership characteristics. COC use up to ten years prior to symptom onset was obtained from the complete electronic health record. We identified 400 women with incident MS/CIS and 3904 matched controls. Fortypercent of cases and 32% of controls had used COCs prior to symptom onset. The use of COCs was associated with a slightly increased risk of MS/CIS (adjusted OR = 1.52, 95%CI = 1.21-1.91; p<0.001). This risk did not vary by duration of COC use. The association varied by progestin content being more pronounced for levenorgestrol (adjusted OR = 1.75, 95%CI = 1.29-2.37; p<0.001) than norethindrone (adjusted OR = 1.57, 95%CI = 1.16-2.12; p = 0.003) and absent for the newest progestin, drospirenone (p = 0.95). Our findings should be interpreted cautiously. While the use of some combination oral contraceptives may contribute to the rising incidence of MS in women, an unmeasured confounder associated with the modern woman's lifestyle is a more likely explanation for this weak association.
PMID 8449016 8449016 DOI 10.1016/0010-7824(93)90088-o 10.1016/0010-7824(93)90088-o Villard-Mackintosh et al. 1993, Villard-Mackintosh 1993
Cite this article
Villard-Mackintosh L, & Vessey, M. (1993). Oral contraceptives and reproductive factors in multiple sclerosis incidence. Contraception, 47(2), 161-168. https://doi.org/10.1016/0010-7824(93)90088-o
Villard-Mackintosh L, Vessey M. Oral contraceptives and reproductive factors in multiple sclerosis incidence. Contraception. 1993;47(2):161-168. doi:10.1016/0010-7824(93)90088-o
Villard-Mackintosh L, and Martin Vessey. "Oral contraceptives and reproductive factors in multiple sclerosis incidence." Contraception, vol. 47, no. 2, 1993, pp. 161-168.