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 Women who have had their appendix or tonsils removed appear to be more fertile, a 15-year study suggests. 
 
 The researchers, at the University of Dundee, analysed medical records from more than half a million British women. 
 
 They argue the operations could directly affect fertility or there may be a "behavioural" explanation. 
 
 Experts said the findings might lead to new treatments, but advised women not to have their tonsils and appendix taken out unnecessarily. 
 
 The study found that for every 100 pregnancies in women who had had no procedures there were: 
 
 134 pregnancies in women who had had their appendix removed 
 
 149 pregnancies in women who had had their tonsils removed 
 
 and 143 pregnancies in women who had had both removed 
 
 One of the researchers, Dr Sami Shimi, said most doctors were wrongly taught that having an appendix removed damaged fertility. 
 
 'Reassuring' 
 
 He told BBC News: "This [study] is very important in reassuring young women that appendicectomy will not reduce their chances of future pregnancy. 
 
 "More importantly, looking at both the appendix and tonsils together, this study confirms beyond doubt that removal of inflamed organs or organs likely to suffer from repeated inflammation, in women, improves their chances of pregnancy." 
 
 Explaining the findings, published in Fertility and Sterility, is more of a challenge. 
 
 Image copyright PA Image caption Medical records from more than half a million British women were analysed by researchers 
 
 One biological possibility is that regularly infected tonsils or appendixes raise levels of inflammation in the body, which affects the ovaries and womb. 
 
 The Dundee team favour a behavioural explanation such as women enjoying more "liberal sexual activity", being both more likely to get pregnant and have pelvic inflammatory disease, which could lead to an appendix being removed. 
 
 More research is needed to figure this out. 
 
 'Interesting paper' 
 
 Prof Allan Pacey, from the University of Sheffield, told the BBC: "This is an interesting paper which suggests that surgical removal of the appendix or tonsils (or both) in young women is associated with an increase in their fertility later in life. 
 
 "There are several explanations which may account for these observations, one of which is that the removal of these tissues makes an alteration to their immune system which has an impact to some aspect of the reproductive process (such as how their embryos implant in the womb). 
 
 "If true, this may ultimately give doctors and scientists some new ideas for novel drugs or therapies to enhance women's fertility. 
 
 "But to suggest that infertile women have their tonsils or appendix removed as a way of improving their chances is a step too far at this stage." 
 
 Follow James on Twitter. ||||| (CNN) Have you had your tonsils or appendix removed? If you have and you're a woman, you probably weren't told that the surgery may have increased your chances of having a baby. 
 
 In fact, you may have been told the opposite. 
 
 But a new 15-year study found that women who had their tonsils or appendix removed when they were young are more likely to get pregnant -- and to do so earlier in life. 
 
 The reasons behind the link are not fully understood. 
 
 Researchers at the University of Dundee examined the medical records of more than 530,000 women across the United Kingdom and found pregnancy rates to be higher among women who had had their tonsils or appendix removed. Pregnancies were even higher among people missing both. 
 
 Rates of pregnancy among women without an appendix or tonsils were 54% and 53%, respectively, and rates in women lacking both parts of their body were 59%. This was higher than pregnancies among the group representing the rest of the population, which was almost 44%. 
 
 The findings go against previous theories in medicine that these surgeries, particularly appendectomies, reduce chances of fertility due to scar tissue forming around a woman's fallopian tubes, where her eggs travel. 
 
 "The study has challenged the myth that was previously accepted on the deleterious effects of appendectomies," said Dr. Sami Shimi , a consultant surgeon and clinical lecturer in surgery at the University of Dundee who led the study. "Young women should not have any fear or anxiety about an appendectomy (or tonsillectomy) reducing their fertility." 
 
 The current research follows a report in 2012 that linked appendectomies to higher rates of pregnancy. The new study backs this previous insight on a wider scale but added the extra association with tonsillectomies and people who have undergone both surgeries. 
 
 Biology or behavior? 
 
 It's hoped the findings will reassure women who need these surgeries, but the researchers are now eager to understand why fertility was seen to increase. 
 
 "We now need to find the mechanism," Shimi said. He believes there could be either a biological or behavioral reason behind it. "We're not discounting either for now." 
 
 The biological contender is the idea that inflammation within the body from a continually inflamed appendix, or tonsils, puts strain and burden on the body, weakening it and potentially reducing chances of conception. 
 
 Alternatively, Shimi suggests that increased promiscuity among some women, and therefore increased contact and intimacy -- through kissing or sex -- may directly increase chances of tonsillitis or else chances of abdominal infection. The latter would not cause appendicitis as such but could lead to more abdominal infections or pain, which is more likely to lead to hospital referrals and investigations in which an inflamed appendix may be spotted more readily. 
 
 Both options need further investigation. 
 
 "It's a very interesting association they've shown here," said Richard Anderson , professor of clinical reproductive science at the University of Edinburgh, who wasn't involved in the new study. "The issue is that it's purely an association." 
 
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 Anderson warns that people may believe that the two factors -- the surgeries and fertility -- are causally linked, but "there's no evidence of that here." He added that the real question now is whether women who undergo these surgeries are more fertile or whether they are more likely to get pregnant at a younger age. 
 
 "Tonsillectomies are rare these days," he added. "It's whether women who chose to have their tonsils removed (rather than ongoing rounds of antibiotics) are also choosing to fall pregnant more often." 
 
 Both Anderson and Shimi agree that the findings should instead be used to reassure women who need the surgeries and that those wanting to improve their fertility should not request to have them. 
 
 "Young women should not seek appendectomies or tonsillectomies to increase their chances of pregnancy," Shimi said. "But if they need one, the operation will not reduce their future chances of pregnancy." ||||| The findings are surprising as most doctors believe that an appendectomy can damage fertility by blocking the fallopian tubes. The researchers warn that many women who sought fertility help may have been wrongly told their failure to get pregnant was down to having their appendix removed. 
 
 “For many years medical students were taught that appendectomy had a negative effect on fertility and young women often feared that having their appendix removed threatened their chances of later becoming pregnant,” said Sami Shimi, Clinical Senior Lecturer in the School of Medicine at the University of Dundee and a consultant surgeon with NHS Tayside. 
 
 “We have found that women who have had an appendectomy or tonsillectomy, or even more particularly both, are more likely to become pregnant, and sooner than the rest of the general population. 
 
 “This scientifically challenges the myth of the effect of appendectomy on fertility. What we have to establish now is exactly why that is the case.” 
 
 Mr Shimi said it was possible that women who suffered from appendix problems may simply have more sexual intercourse, which can cause pelvic inflammation. But reducing inflammation in the pelvis through an appendectomy could reverse any problems, making pregnancy easier. ||||| OBJECTIVE: 
 
 To study pregnancy rates after appendectomy and/or tonsillectomy. 
 
 DESIGN: 
 
 Population-based cohort study using the United Kingdom (U.K.) primary health care-based Clinical Practice Research Datalink (CPRD). 
 
 SETTING: 
 
 Not applicable. 
 
 PATIENT(S): 
 
 Female patients who underwent appendectomy, tonsillectomy, or both from 1987 to 2012 and appropriate comparators. 
 
 INTERVENTION(S): 
 
 Timed follow-up until first pregnancy after surgery. The association between prior surgery and subsequent pregnancy was determined with the use of Cox regression models. 
 
 MAIN OUTCOME MEASURE(S): 
 
 Pregnancy rate and time to first pregnancy after surgery. 
 
 RESULT(S): 
 
 The analyses included 54,675 appendectomy-only patients, 112,607 tonsillectomy-only patients, 10,340 patients who had both appendectomy and tonsillectomy, and 355,244 comparators matched for exact age and practice from the rest of female patients in the database. There were 29,732 (54.4%), 60,078 (53.4%), and 6,169 (59.7%) pregnancies in the appendectomy-only, tonsillectomy-only, and both appendectomy tonsillectomy cohorts, respectively versus 155,079 (43.7%) in the comparator cohort during a mean follow-up of 14.7 ± 9.7 years. Adjusted hazard ratios (HRs) for subsequent birth rates were 1.34 (95% confidence interval [CI] 1.32-1.35), 1.49 (95% CI 1.48-1.51), and 1.43 (95% CI 1.39-1.47), respectively. Time to pregnancy was shortest after both appendectomy and tonsillectomy followed by appendectomy only and then tonsillectomy only compared with the rest of the population. 
 
 CONCLUSION(S): 
 
 Appendectomy and/or tonsillectomy was associated with increased subsequent pregnancy rates and shorter time to pregnancy. The effect of the surgical procedures on the pregnancy outcome was cumulative. 
 
 Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
– Having their tonsils or appendix removed might result in an unexpected benefit for young women who hope to become pregnant someday: New research suggests they might be more fertile as a result. A 15-year study of half a million British women finds that a woman who has undergone a tonsillectomy or appendectomy has a 49% and 34% higher chance of getting pregnant, respectively, than a woman with her appendix and tonsils intact, reports the Telegraph. A woman who's had both procedures has a 43% higher chance of getting pregnant. One of the researchers says the study "confirms beyond doubt that removal of inflamed organs or organs likely to suffer from repeated inflammation, in women, improves their chances of pregnancy" rather than reduces those chances, as some doctors believe. It isn't clear why the procedures are linked to increased fertility—doctors previously suggested scar tissue around the fallopian tubes after an appendectomy reduced the chance of pregnancy—but it may simply be that women who have more sex are more likely to develop an infection. However, inflammation in the body can affect a woman's ovaries and womb, per the BBC, and it's possible that "the removal of these tissues makes an alteration to their immune system" that affects reproduction, says a scientist not involved in the study. "If true, this may ultimately give doctors and scientists some new ideas for novel drugs or therapies to enhance women's fertility." The researchers stress they're not advocating that otherwise healthy women have the procedures, notes CNN. (This procedure may double a woman's chance of conception.)