Cancer Risk in Women Treated with Fertility Drugs According to Parity Status-A Registry-based Cohort Study

History of Infertility and Risk of Colorectal Cancer

BACKGROUND

There has been limited prior research on the association between infertility and risk of colorectal cancer.

METHODS

Data from postmenopausal women in the Women's Health Initiative were used to estimate the association between self-reported infertility (12 months of trying to get pregnant without achieving a pregnancy) and the risk of colorectal cancer using Cox proportional hazard models.

RESULTS

No association was observed between infertility and risk of postmenopausal colorectal cancer [RR, 0.97; 95% confidence interval (CI), 0.87-1.08], invasive colorectal cancer (RR, 0.99; 95% CI, 0.88-1.10), or colorectal cancer mortality (RR, 0.89; 95% CI, 0.71-1.12).

CONCLUSIONS

Infertility was not found to be associated with colorectal cancer risk among postmenopausal women. Risk did not vary by specific infertility diagnoses.

IMPACT

Infertility may not be associated with colorectal cancer risk.

Bioelectric pharmacology of cancer: A systematic review of ion channel drugs affecting the cancer phenotype

Cancer is a pernicious and pressing medical problem; moreover, it is a failure of multicellular morphogenesis that sheds much light on evolutionary developmental biology. Numerous classes of pharmacological agents have been considered as cancer therapeutics and evaluated as potential carcinogenic agents; however, these are spread throughout the primary literature. Here, we briefly review recent work on ion channel drugs as promising anti-cancer treatments and present a systematic review of the known cancer-relevant effects of 109 drugs targeting ion channels. The roles of ion channels in cancer are consistent with the importance of bioelectrical parameters in cell regulation and with the functions of bioelectric signaling in morphogenetic signals that act as cancer suppressors. We find that compounds that are well-known for having targets in the nervous system, such as voltage-gated ion channels, ligand-gated ion channels, proton pumps, and gap junctions are especially relevant to cancer. Our review suggests further opportunities for the repurposing of numerous promising candidates in the field of cancer electroceuticals.

Risk of borderline ovarian tumors after fertility treatment - Results from a Danish cohort of infertile women

OBJECTIVE

Results from previous studies examining the association between fertility treatment and borderline ovarian tumors are inconsistent. The aim of this study was to investigate the association between fertility treatment and borderline ovarian tumors in a cohort of infertile women.

METHODS

This cohort study was based on the Danish Infertility Cohort and included all infertile women aged 20-45 years living in Denmark between 1 January 1995 and 31 December 2017 (n = 146,891). Information on use of fertility drugs, borderline ovarian tumors and cancer diagnoses, covariates, emigration, and vital status was obtained by linkage to national registers. Cox proportional hazard models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) with adjustment for potential confounders for overall borderline ovarian tumors and for serous- and mucinous borderline ovarian tumors separately.

RESULTS

During a median 11.3 years of follow-up, 144 women developed a borderline ovarian tumor. No marked associations between ever use of clomiphene citrate, gonadotropins, gonadotropin-releasing hormone receptor modulators, human chorionic gonadotropin or progesterone and borderline ovarian tumors were observed, neither overall nor for serous and mucinous borderline ovarian tumors analysed separately. Further, no clear associations with borderline ovarian tumors were found according to cumulative dose, time since first use or parity status for any fertility drugs.

CONCLUSIONS

No marked associations between use of fertility drugs and borderline ovarian tumors were observed. However, the cohort's relatively young age at end of follow-up emphasizes the importance of extending the follow-up period for women who have used fertility drugs.

Infertility and risk of postmenopausal breast cancer in the women's health initiative

PURPOSE

Although infertility (i.e., failure to conceive after ≥ 12 months of trying) is strongly correlated with established breast cancer risk factors (e.g., nulliparity, number of pregnancies, and age at first pregnancy), its association with breast cancer incidence is not fully understood. Previous studies were primarily small clinic-based or registry studies with short follow-up and predominantly focused on premenopausal breast cancer. The objective of this study was to assess the relationship between infertility and postmenopausal breast cancer risk among participants in the Women's Health Initiative (analytic sample = 131,784; > 25 years of follow-up).

METHODS

At study entry, participants were asked about their pregnancy history, infertility history, and diagnosed reasons for infertility. Incident breast cancers were self-reported with adjudication by trained physicians reviewing medical records. Cox proportional hazards models were used to estimate risk of incident postmenopausal breast cancer for women with infertility (overall and specific infertility diagnoses) compared to parous women with no history of infertility. We examined mediation of these associations by parity, age at first term pregnancy, postmenopausal hormone therapy use at baseline, age at menopause, breastfeeding, and oophorectomy.

RESULTS

We observed a modest association between infertility (n = 23,406) and risk of postmenopausal breast cancer (HR = 1.07; 95% CI 1.02-1.13). The association was largely mediated by age at first term pregnancy (natural indirect effect: 46.4% mediated, CI 12.2-84.3%).

CONCLUSION

These findings suggest that infertility may be modestly associated with future risk of postmenopausal breast cancer due to age at first pregnancy and highlight the importance of incorporating reproductive history across the life course into breast cancer analyses.

Clomiphene Citrate Administered in Periconception Phase Causes Fetal Loss and Developmental Impairment in Mice

Clomiphene citrate is a common treatment for ovulation induction in subfertile women, but its use is associated with elevated risk of adverse perinatal outcomes and birth defects. To investigate the biological plausibility of a causal relationship, this study investigated the consequences in mice for fetal development and pregnancy outcome of periconception clomiphene citrate administration at doses approximating human exposures. A dose-dependent adverse effect of clomiphene citrate given twice in the 36 hours after mating was seen, with a moderate dose of 0.75 mg/kg sufficient to cause altered reproductive outcomes in 3 independent cohorts. Viable pregnancy was reduced by 30%, late gestation fetal weight was reduced by 16%, and ∼30% of fetuses exhibited delayed development and/or congenital abnormalities not seen in control dams, including defects of the lung, kidney, liver, eye, skin, limbs, and umbilicus. Clomiphene citrate also caused a 30-hour average delay in time of birth, and elevated rate of pup death in the early postnatal phase. In surviving offspring, growth trajectory tracking and body morphometry analysis at 20 weeks of age showed postweaning growth and development similar to controls. A dysregulated inflammatory response in the endometrium was observed and may contribute to the underlying pathophysiological mechanism. These results demonstrate that in utero exposure to clomiphene citrate during early pregnancy can compromise implantation and impact fetal growth and development, causing adverse perinatal outcomes. The findings raise the prospect of similar iatrogenic effects in women where clomiphene citrate may be present in the periconception phase unless its use is well-supervised.

Outcomes and the effect of PGT-M in women with hormone-related hereditary tumor syndrome

Purpose

To review the outcome of PGT-M in hormone-related hereditary tumor syndrome and evaluate the effect of ovarian induction on tumor growth in those patients.

Methods

Medical records of PGT-M were retrospectively analyzed in patients with hormone-related heritage tumors in our reproductive center. A total of eleven women with hereditary breast and ovarian cancer (HBOC) (including BRCA1/2 mutation carriers), and Lynch syndrome (including MMR gene mutation carriers) were included. Thirteen IVF/PGT-M cycles were performed. Eleven for PGT-M and two for fertility preservation. The ovulation protocol, numbers of oocytes retrieved and two pronuclei (2PN) zygotes, PGT-M results, and clinical outcomes were analyzed. Tumor progression was also estimated by comparing transvaginal ultrasound (TVS), MR, CT, or colonoscopy according to the follow-up requirements of different tumors.

Results

Eleven IVF/PGT-M cycles were performed with an antagonist protocol; Two cycles were performed with a mild stimulation protocol. The total dose of gonadotropin (Gn) was 1827 IU per patient (range from 1200 to 2625 IU). The median number of oocytes retrieved was 13 (range from 4 to 30), and the median number of 2PN zygotes was 8 (range from 2 to 16). A total of 32 embryos underwent PGT-M, and 9 (28.1%) embryos were suitable for transfer. Six transfer cycles were performed, and 5 cycles got clinical pregnancy (83%) with five newborns (83%). The follow-up examinations conducted 10-18 months after PGT-M/delivery revealed no new lesions or tumor progression.

Conclusion

PGT-M results can provide important information for improving the consultation of hormone-related heritage tumor patients regarding their fertility preservation and reproductive options. Ovarian induction for women with hormone-related hereditary tumor syndrome is not associated with tumor progression.

Estimating the impact of bias in causal epidemiological studies: the case of health outcomes following assisted reproduction

Researchers interested in causal questions must deal with two sources of error: random error (random deviation from the true mean value of a distribution), and bias (systematic deviance from the true mean value due to extraneous factors). For some causal questions, randomization is not feasible, and observational studies are necessary. Bias poses a substantial threat to the validity of observational research and can have important consequences for health policy developed from the findings. The current piece describes bias and its sources, outlines proposed methods to estimate its impacts in an observational study, and demonstrates how these methods may be used to inform debate on the causal relationship between medically assisted reproduction (MAR) and health outcomes, using cancer as an example. In doing so, we aim to enlighten researchers who work with observational data, especially regarding the health effects of MAR and infertility, on the pitfalls of bias, and how to address them. We hope that, in combination with the provided example, we can convince readers that estimating the impact of bias in causal epidemiologic research is not only important but necessary to inform the development of robust health policy and clinical practice recommendations.

The risk of breast cancer and gynecologic malignancies after ovarian stimulation: Meta-analysis of cohort study

The effects of ovarian stimulation on breast and gynecological tumor incidence remain controversial. Therefore, the aim of this meta-analysis was to study the risk of cancer in ovarian stimulation. Of the 22713 studies initially identified, 28 were eligible for inclusion. The results revealed that the impact of ovarian cancer (RR = 1.33, [1.05; 1.69]) and cervical cancer (RR = 0.67, [0.46; 0.97]) is significant among the overall effects. In subgroup analysis, in the nulliparous population (RR = 0.81 [0.68; 0.96]) was the protective factor for the breast cancer. In the Caucasians subgroup (RR = 1.45, [1.12; 1.88]), the ovarian cancer incidence was statistically significant. In the Asian subgroup (RR = 1.51, [1.00; 2.28]), the endometrial cancer incidence was statistically significant. In the subgroup of Asians (RR = 0.55 [0.44; 0.68]) and the multiparous population (RR = 0.31, [0.21; 0.46]), them can be the statistically protective factor for the cervical cancer.

Effects of Infertility Drug Exposure on the Risk of Borderline Ovarian Tumors: A Systematic Review and Meta-Analysis

Whether infertility drug exposure increases the risk of borderline ovarian tumors (BOTs) remains controversial. The present study was conducted with a comprehensive search for studies published from January 1990 to December 2021 in the online databases Cochrane Library, PubMed, Web of Science and EMBASE. We considered the first diagnosis of a BOT as the primary outcome. The odds ratio (OR) was calculated with corresponding 95% confidence intervals (CIs) for the risk of BOTs in patients who were treated with infertility drugs. Ten studies, a total of 2,779,511 women, qualified for inclusion in this meta-analysis. The pooled OR of 1.56 (95% CI: 1.09-2.22) revealed a significant positive association between infertility drugs and an increased risk for BOTs, but for specific drugs, only CC plus Gn had statistical significance. No publication bias was detected using the Egger and Begg tests (p > 0.05). A significant difference in BOT incidence was observed among infertile women and nulliparous women who were treated with or without infertility drugs. In conclusion, the use of infertility drugs may increase the risk of BOTs, but a dose-dependent relationship was not observed between the number of assisted reproduction technology cycles and the risk of BOTs, and infertile women who successfully became pregnant might have a reduced risk. Registration: PROSPERO, CRD42022330775.

History of infertility and risk of breast cancer: a prospective cohort study

PURPOSE

Research on infertility and risk of breast cancer has been conflicting, potentially because many well-established breast cancer risk factors, such as pregnancy history, are strongly correlated with infertility.

METHODS

We followed participants in the Nurses' Health Study II from 1989 to 2015 (n = 103,080) for the development of invasive breast cancer and calculated Hazard Ratios (HR) and 95% confidence intervals (CI) using Cox regression. Participants with a self-reported history of infertility (12 months of trying without conception) were compared to gravid women with no history of infertility. We classified breast cancer by menopausal status and investigated mediation by reproductive factors.

RESULTS

Over 26 years of follow-up, 26,208 (25.4%) women reported a history of infertility, and 3,201 women were newly diagnosed with invasive breast cancer. We observed no association between infertility history and risk of overall breast cancer (HR: 1.05, 95% CI: 0.97-1.14) or premenopausal breast cancer (RR: 0.93, 95% CI: 0.83-1.03). However, we observed a modest association between history of infertility and risk of postmenopausal breast cancer (HR: 1.13, 95% CI: 1.00-1.28), approximately 50% of which could be attributed to lower total parity and later age at first birth (95% CI: 8.2%-91.0%).

CONCLUSIONS

Women with a history of infertility were at increased risk of postmenopausal breast cancer. Older age at first birth and lower total parity explained approximately half of the association between infertility and risk of postmenopausal breast cancer.

Risk of ovarian cancer in women who give birth after assisted reproductive technology (ART)-a registry-based Nordic cohort study with follow-up from first pregnancy

BACKGROUND

There is concern that assisted reproductive technology (ART) may increase ovarian cancer risk, but previous studies are inconclusive. We compared ovarian cancer risk for women who gave birth after ART vs natural conception.

METHODS

Through linkage of nationwide registry data, we followed 3,303,880 initially nulliparous women in Denmark (1994-2014), Finland (1990-2014), Norway (1984-2015) and Sweden (1985-2015) from first pregnancy ≥22 weeks to ovarian cancer, emigration, death or end of follow-up (2014/2015). We estimated hazard ratios (HRs), adjusting for age, parity, maternal birth year and country, and for body mass index and smoking in subsamples.

RESULTS

Mean age at first birth was 27.7 years. During a mean follow-up of 14.4 person-years, 2683 participants (0.08%) developed ovarian cancer; 135 after ART and 2548 after natural conception only (incidence rates 11.6 and 5.5 per 100,000 person-years, respectively). The risk was higher for women who ever gave birth after ART (HR 1.70, 95% confidence interval 1.42-2.03) compared to natural conception. Associations were stronger for conventional in vitro fertilisation than for intracytoplasmic sperm injection.

CONCLUSIONS

Among parous women, ART-conception was associated with a higher risk of ovarian cancer than natural conception. Further studies should decipher whether this is causal or confounded by infertility or other factors.

Epidemiological trends and risk factors of gynecological cancers: an update

Gynecological cancers, the most common cancer among women worldwide, disrupt the function of women's reproductive system, significantly impacting the quality of life. The epidemiological patterns of gynecological cancers differ in various regions and alter over time. The main challenge to deal with women's cancers is focusing on potential plans to improve patient outcomes. The epidemiology and general risk elements of gynecological cancers are important in the management of these cancers, so all of the reported risk factors in gynecological cancers have been evaluated in the present review. Due to the role of gynecological cancers in women's health, preventive measures and modifiable lifestyles together with early detection in high-risk groups are effective strategies that can reduce mortality rates. This review summarizes the epidemiology and global risk factors of gynecological cancers alongside others to better management of these malignancies and improve the quality of life in the affected patients.

Ovulation induction drug and ovarian cancer: an updated systematic review and meta-analysis

OBJECTIVE

To explore the association between ovulation induction drugs and ovarian cancer.

DESIGN

Systematic review and meta-analysis.

SETTING

Not applicable.

PATIENT(S)

Women without ovarian cancer who ever or never underwent ovarian induction.

INTERVENTION(S)

An extensive electronic search of the following databases was performed: PubMed, EMBASE, MEDLINE, Google Scholar, Cochrane Library and CNKI, from inception until January 2022. A total of 34 studies fulfilled our inclusion criteria and were included in the final meta-analysis. The odds ratio (OR) and random-effects model were used to estimate the pooled effects. The Newcastle-Ottawa Scale was used to assess the quality of included studies. Funnel plots and Egger tests were used to assess publication bias.

MAIN OUTCOMES

New diagnosed borderline ovarian tumor (BOT) and invasive ovarian cancer (IOC) between ovulation induction (OI) group and control (CT) group considering fertility outcome, OI cycles and specific OI drugs.

RESULTS

Primarily, there was no significant difference in the incidence of IOC and BOT between the OI and CT groups. Secondly, OI treatment did not increase the risk of IOC and BOT in the multiparous women, nor did it increase the risk of IOC in the nulliparous women. However, the risk of BOT appeared to be higher in nulliparous women treated with OI treatment. Thirdly, among women exposed to OI, the risk of IOC and BOT was higher in nulliparous women than in multiparous women. Fourthly, the risk of IOC did not increase with increasing OI cycles. Lastly, exposure to specific OI drugs also did not contribute to the risk of IOC and BOT.

CONCLUSION

Overall, OI treatment did not increase the risk of IOC and BOT in most women, regardless of OI drug type and OI cycle. However, nulliparous women treated with OI showed a higher risk of ovarian cancer, necessitating their rigorous monitoring and ongoing follow-up.

Risk of colorectal cancer after use of fertility drugs-results from a large Danish population-based cohort of women with infertility

OBJECTIVE

To study the association between use of fertility drugs and colorectal cancer among women with infertility.

DESIGN

Population-based cohort study.

SETTING

Not applicable.

PATIENT(S)

The study cohort was obtained from the Danish Infertility Cohort and consisted of all women with infertility aged 20-45 years living in Denmark during 1995-2017.

INTERVENTION(S)

Information on the use of specific types of fertility drugs, colorectal cancer diagnoses, covariates, and vital status were obtained from the Danish Infertility Cohort and Danish national registers.

MAIN OUTCOME MEASURE(S)

Cox proportional hazard models adjusted for potential confounders were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for colorectal cancer overall and rectal and colon cancer separately.

RESULTS(S)

Among 148,036 women in the final study cohort, 205 women were diagnosed with colorectal cancer. Ever use of clomiphene citrate (CC) was associated with a lower rate of colorectal cancer (unadjusted HR, 0.67; 95% CI, 0.51-0.89; adjusted HR, 0.68; 95% CI, 0.50-0.93). However, the lower rate was only seen among women who first used CC >8 years ago (unadjusted HR, 0.56; 95% CI, 0.41-0.76; adjusted HR, 0.52; 95% CI, 0.36-0.75). No marked associations were found between the use of any of other types of fertility drugs and colorectal cancer. The results for colon and rectal cancer analyzed separately were similar, except for a suggestion of a decreased risk of rectal cancer associated with the use of gonadotropins (adjusted HR, 0.46; 95% CI, 0.20-1.08).

CONCLUSION(S)

Among women with infertility, the use of most types of fertility drugs was not associated with colorectal cancer. However, CC may decrease the risk of colorectal cancer and gonadotropins might decrease the risk of rectal cancer, but we cannot rule out that these findings may be more related to the underlying conditions in these women or are chance findings. Consequently, the results from this study should be investigated further in large epidemiological studies.

Tumors of the central nervous system among women treated with fertility drugs: a population-based cohort study

PURPOSE

To investigate the association between fertility drugs and tumors of the central nervous system (CNS).

METHODS

This cohort study was based on The Danish Infertility Cohort and included 148,016 infertile women living in Denmark (1995-2017). The study cohort was linked to national registers to obtain information on use of specific fertility drugs, cancer diagnoses, covariates, emigration, and vital status. Cox proportional hazard regression models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for all CNS tumors and separately for gliomas, meningiomas and diverse benign tumors of the brain and other parts of the CNS.

RESULTS

During a median 11.3 years of follow-up, 328 women were diagnosed with CNS tumors. No marked associations were observed between use of the fertility drugs clomiphene citrate, gonadotropins, gonadotropin-releasing hormone receptor modulators and progesterone and CNS tumors. However, use of human chorionic gonadotropin was associated with a decreased rate of meningiomas (HR 0.49 95% CI 0.28-0.87). No clear associations with CNS tumors were observed according to time since first use or cumulative dose for any of the fertility drugs.

CONCLUSION

No associations between use of most types of fertility drugs and CNS tumors were observed. However, our findings only apply to premenopausal women and additional studies with longer follow-up time are necessary.

Pharmacogenetic Review: Germline Genetic Variants Possessing Increased Cancer Risk With Clinically Actionable Therapeutic Relationships

As our understanding of genomics and genetic testing continues to advance, the personalization of medical decision making is progressing simultaneously. By carefully crafting medical care to fit the specific needs of the individual, patients can experience better long-term outcomes, reduced toxicities, and improved healthcare experiences. Genetic tests are frequently ordered to help diagnose a clinical presentation and even to guide surveillance. Through persistent investigation, studies have begun to delineate further therapeutic implications based upon unique relationships with genetic variants. In this review, a pre-emptive approach is taken to understand the existing evidence of relationships between specific genetic variants and available therapies. The review revealed an array of diverse relationships, ranging from well-documented clinical approaches to investigative findings with potential for future application. Therapeutic agents identified in the study ranged from highly specific targeted therapies to agents possessing similar risk factors as a genetic variant. Working in conjunction with national standardized treatment approaches, it is critical that physicians appropriately consider these relationships when developing personalized treatment plans for their patients.

Hospitalizations up to 8 years following delivery in assisted reproductive technology-treated and subfertile women

OBJECTIVE

To investigate hospitalizations up to 8 years after live birth among women who used assisted reproductive technology (ART) or who were subfertile compared with women who conceived naturally.

DESIGN

Retrospective cohort.

SETTING

Deliveries among privately insured women aged ≥18 years between 2004 and 2017 from Massachusetts state vital records were linked to the Society for Assisted Reproductive Technology Clinic Outcome Reporting System and hospital observational/inpatient stays.

PATIENT(S)

We compared patients with ART, medically assisted reproduction (MAR), and unassisted subfertile (USF) delivery with those with fertile delivery.

INTERVENTION(S)

NA.

MAIN OUTCOME MEASURE(S)

Postdelivery hospitalization information was derived from the International Classification of Diseases codes for discharges and combined by type. The relative risks and 95% confidence intervals (CIs) of hospitalization for up to the first 8 years postdelivery were modeled.

RESULT(S)

Among 492,515 deliveries, 5.6% used ART, 1.6% used MAR, and 1.8% were USF. Compared with fertile deliveries, deliveries that used ART or MAR or were USF were more likely to have hospital utilization (inpatient or observational stay) for any reason for up to 8 years of follow-up (USF, adjusted relative risk [aRR], 1.18 [95% CI, 1.12-1.25]; MAR, aRR, 1.20 [1.13-1.27]; and ART, aRR, 1.29 [1.25-1.34]). Assisted reproductive technology deliveries had an increased risk of hospitalization for conditions of the cardiovascular system (aRR, 1.31 [95% CI, 1.20-1.41]), overweight/obesity (aRR, 1.30 [1.17-1.44]), diabetes (aRR, 1.25 [1.05-1.49]), reproductive tract (aRR, 1.62 [1.47-1.79]), digestive tract (aRR, 1.39 [1.30-1.49]), thyroid (aRR, 2.02 [1.80-2.26]), respiratory system (aRR, 1.13 [1.03-1.24]), and cancer (aRR, 1.40 [1.18-1.65]) up to 8 years after delivery. Deliveries with MAR and subfertility had similar patterns of hospitalization as ART deliveries.

CONCLUSION(S)

Women who conceived through fertility treatment or experienced subfertility were at increased risk of subsequent hospitalization resulting from a variety of chronic and acute conditions.

Ovarian stimulation for fertility treatments and risk of breast cancer: a matched cohort study

STUDY QUESTION

Is there a difference in the breast cancer risk among women who underwent ART treatments compared to those who underwent medically assisted reproduction (MAR) infertility treatments or women of reproductive age in the general population?

SUMMARY ANSWER

The risk of breast cancer among women treated by ART was similar to the risk among women treated by MAR and women who did not undergo fertility treatments.

WHAT IS KNOWN ALREADY

Studies investigating breast cancer risk in women who have undergone fertility treatments have provided conflicting results.

STUDY DESIGN, SIZE, DURATION

A retrospective, population-based cohort study included women who underwent ART or MAR treatments and women who did not undergo fertility treatments from 1994 to 2019.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Women who underwent ART were matched one to one with women who underwent MAR treatments and one to one with woman from the general population of reproductive age, by year of birth and year of first delivery or nulliparity status. MAR women were also matched to ART women by treatment initiation calendar year. All included women were members of Maccabi Healthcare Services. Data regarding demographics, fertility treatments, BRCA mutation and possible confounders were obtained from the computerized database of electronic health records. The incidence of breast cancer after fertility treatments was compared to the matched controls.

MAIN RESULTS AND THE ROLE OF CHANCE

Of 8 25 721 women of reproductive age, 32 366 women who underwent ART were matched with patients treated by MAR (n = 32 366) and 32 366 women of reproductive age. A total of 984 women (1.0%) were diagnosed with breast cancer (mean follow-up period, 9.1 ± 6.3 years; interquartile range [IQR], 3.8-13.7 years). The incidence rates of breast cancer per 10 000 person-years were 11.9 (95% CI, 10.7-13.3), 10.7 (95% CI, 9.6-11.9) and 10.7 (95% CI, 9.6-12.0) in the ART group, MAR group and general population, respectively. The crude risk for breast cancer was similar in the ART group compared with the general population (hazard ratio (HR) = 1.10, 95% CI, 0.94-1.28) and in the ART group compared with the MAR group (HR = 1.00, 95% CI, 0.86-1.16). Further adjustment for age, BMI, smoking, socioeconomic status and parity did not substantially impact the hazard rates for breast cancer (ART vs general population: HR = 1.10, 95% CI, 0.94-1.28; ART vs MAR: HR = 0.99, 95% CI, 0.85-1.16). Among women diagnosed with breast cancer, the prevalence of BRCA1/2 mutations and tumour staging did not differ between the ART, MAR and general population groups. Among women who underwent ART, no correlation was found between breast cancer and the number of ART cycles or the use of recombinant medications or urine-derived medications.

LIMITATIONS, REASONS FOR CAUTION

The mean age of women at the end of follow-up was only 42 years thus the study was not powered to detect potential differences in the risk of postmenopausal breast cancer. In addition, we did not sub-classify the exposed patients by the reason for infertility.

WIDER IMPLICATIONS OF THE FINDINGS

Breast cancer incidence following ART was comparable to that in the general population or following MAR. Women undergoing fertility treatments and their clinicians may be reassured about the safety of assisted reproduction technologies in terms of premenopausal breast cancer risk.

STUDY FUNDING/COMPETING INTEREST(S)

No specific funding was used and there are no competing interests.

TRIAL REGISTRATION NUMBER

N/A.

Thyroid nodules and thyroid cancer in women with positive thyroid screening in pregnancy: a double-centric, retrospective, cohort study

OBJECTIVE

Thyroid nodules are a common finding in the general population. The primary aim of the study was to determine the prevalence of thyroid nodules and cancer found by ultrasound (US) in women who underwent screening for thyroid dysfunction during pregnancy.

DESIGN

A double-centric, retrospective, cohort study.

PATIENTS AND METHODS

We searched through medical records, including thyroid ultrasonography, of pregnant women who were positively screened for thyroid disorders (using thyroid-stimulating hormone and thyroid antibodies) from an unselected population ('universal screening group', n = 690) and of women who underwent the testing based on the presence of clinical risk factors defined by American Thyroid Association ('case-finding group', n = 249).

RESULTS

Prevalence of benign and malignant thyroid nodules was lower in the 'universal screening group' than in the 'case-finding group' (9.9% vs 17.7%, P= 0.002, and 0.9% vs 7.2%, P< 0.001, respectively). Consistently, the thyroid cancer rate was lower among the nodules in the 'universal screening group' than in the 'case-finding group' (8.1% vs 29.0%, P= 0.003). Ultrasound EU-TIRADS (European Thyroid Imaging and Reporting Data System) category ≥4 had a 95.8% sensitivity for thyroid cancer. In palpable nodules, the prevalence of cancer was significantly higher than in the non-palpable ones (44.0% vs 2.2%, P < 0.001). In a multivariate regression analysis, thyroid nodules were associated with a history of infertility and parity.

CONCLUSIONS

Compared to the data from cancer registries, universal screening allowed detecting thyroid cancer in pregnancy three to five times more frequently, but the cancer rate among nodules (8.1%) did not differ from the common population. US had very good sensitivity for thyroid cancer in pregnancy.

Fertility drugs and incidence of thyroid cancer in a Danish nationwide cohort of 146 024 infertile women

STUDY QUESTION

Do fertility drugs increase the risk of thyroid cancer among infertile women?

SUMMARY ANSWER

The use of most types of fertility drugs was not associated with an increased risk of thyroid cancer.

WHAT IS KNOWN ALREADY

The incidence of thyroid cancer is higher for women than men, especially during reproductive years, indicating that reproductive hormones may be involved in the development of thyroid cancer. Only a few previous studies have examined the association between the use of fertility drugs and incidence of thyroid cancer and the results are inconclusive.

STUDY DESIGN, SIZE, DURATION

A retrospective, population-based cohort study including all 146 024 infertile women aged 20-45 years and living in Denmark in the period 1995-2017. The women were followed from the date of entry in the cohort (i.e. date of first infertility diagnosis) until the occurrence of thyroid cancer or any other cancer (except non-melanoma skin cancer), death, emigration, total thyroidectomy or the end of follow-up (31 December 2018), whichever occurred first. The median length of follow-up was 11.3 years.

PARTICIPANTS/MATERIALS, SETTING, METHODS

In total, 167 women were diagnosed with thyroid cancer during the follow-up period. Information on the use of specific fertility drugs (clomiphene citrate, gonadotropins, hCGs, GnRH receptor modulators and progesterone), thyroid cancer, covariates and vital status was obtained from the Danish Infertility Cohort and various Danish national registers. Cox proportional hazard regression models were used to calculate hazard ratios (HRs) and 95% CIs for thyroid cancer overall and for papillary thyroid cancer.

MAIN RESULTS AND THE ROLE OF CHANCE

After adjustment for the calendar year of infertility diagnosis, the highest obtained level of education, parity status, obesity or thyroid disease and mutual adjustment for other registered fertility drugs, no marked associations were observed between the use of clomiphene citrate, hCG, gonadotropins or GnRH receptor modulators and risk of overall or papillary thyroid cancer. However, ever use of progesterone was associated with an increased rate of both overall (HR 1.63; 95% CI 1.07-2.48) and papillary (HR 1.66, 95% CI 1.04-2.65) thyroid cancer after mutual adjustment for other specific fertility drugs. For most specific fertility drugs, we observed a tendency toward higher associations with thyroid cancer within the first 5 years after the start of drug use than after 5 years from the start of use. No marked associations were detected according to the cumulative dose for any of the specific fertility drugs.

LIMITATIONS, REASONS FOR CAUTION

Despite a large study population, the statistical precision in some subgroup analyses may be affected due to the low number of thyroid cancer cases. Although we were able to adjust for a number of potential confounders, residual and unmeasured confounding may potentially have affected the observed associations, as we could not adjust for some factors that may influence the association between fertility drugs and thyroid cancer, including age at menarche and BMI.

WIDER IMPLICATIONS OF THE FINDINGS

Although this study, which is the largest to date, provides reassuring evidence that there is no strong link between the use of fertility drugs and thyroid cancer incidence, we observed a modest increased thyroid cancer incidence after the use of progesterone. However, we cannot rule out that this is a chance finding and the potential association between the use of progesterone and thyroid cancer should therefore be investigated further in large epidemiological studies. The results of the present study provide valuable knowledge for clinicians and other health care personnel involved in the diagnosis and treatment of infertility.

STUDY FUNDING/COMPETING INTEREST(S)

The study was supported by research grants from the Jascha Foundation and the Aase and Ejner Danielsens Foundation. B.N. received honoraria and/or non-financial support by Gedeon Richter Nordics AB, IBSA Nordic APS and Merck KGAA. The remaining authors have no competing interests.

TRIAL REGISTRATION NUMBER

N/A.

Assisted reproductive technology treatment and risk of breast cancer: a population-based cohort study

STUDY QUESTION

Is there an increased risk of breast cancer among women after ART treatment including ovarian hormone stimulation?

SUMMARY ANSWER

The risk of breast cancer was slightly increased among women after ART treatment compared to age-matched, untreated women in the background population, and the risk was further increased among women initiating ART treatment when aged 40+ years.

WHAT IS KNOWN ALREADY

The majority of breast cancer cases are sensitive to oestrogen, and ovarian hormone stimulation has been suggested to increase the risk of breast cancer by influencing endogenous oestrogen levels. Previous studies on ART treatment and breast cancer have varied in their findings, but several studies have small sample sizes or lack follow-up time and/or confounder adjustment. Recent childbirth, nulliparity and higher socio-economic status are breast cancer risk factors and the latter two are also associated with initiating ART treatment.

STUDY DESIGN, SIZE, DURATION

The Danish National ART-Couple II (DANAC II) cohort includes women treated with ART at public and private fertility clinics in 1994-2016.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Women with no cancer prior to ART treatment were included (n = 61 579). Women from the background population with similar age and no prior history of ART treatment were randomly selected as comparisons (n = 579 760). The baseline mean age was 33.1 years (range 18-46 years). Results are presented as hazard ratios (HRs) with corresponding CIs.

MAIN RESULTS AND THE ROLE OF CHANCE

During follow-up (median 9.69 years among ART-treated and 9.28 years among untreated), 5861 women were diagnosed with breast cancer, 695 among ART-treated and 5166 among untreated women (1.1% versus 0.9%, P < 0.0001). Using Cox regression analyses adjusted for nulliparity, educational level, partnership status, year, maternal breast cancer and age, the risk of breast cancer was slightly increased among women treated with ART (HR 1.14, 95% CI 1.12-1.16). All causes of infertility were slightly associated with breast cancer risk after ART treatment. The risk of breast cancer increased with higher age at ART treatment initiation and was highest among women initiating treatment at age 40+ years (HR 1.37, 95% CI 1.29-1.45). When comparing women with a first birth at age 40+ years with or without ART treatment, the increased risk among women treated with ART persisted (HR 1.51, 95% CI 1.09-2.08).

LIMITATIONS, REASONS FOR CAUTION

Although this study is based on a large, national cohort of women, more research with sufficient power and confounder adjustment is needed, particularly in cohorts with a broad age representation.

WIDER IMPLICATIONS OF THE FINDINGS

An increased risk of breast cancer associated with a higher age at ART treatment initiation has been shown. Ovarian stimulation may increase the risk of breast cancer among women initiating ART treatment when aged 40+ years. Age-related vulnerability to hormone exposure or higher hormone doses during ART treatment may explain the increased risk.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by a PhD grant to D.V. from the Faculty of Health and Medical Sciences, University of Copenhagen, Denmark. Funding for establishing the DANAC II cohort was received from the Ebba Rosa Hansen Foundation. The authors report no conflict of interest.

TRIAL REGISTRATION NUMBER

N/A.

The complex relationship between infertility and female genital tract cancer: A review

INTRODUCTION

The link between female infertility and gynecological cancer has always been a debated and challenging topic. Although cervical cancer has the worst impact on female fertility, as it is usually diagnosed in patients of reproductive age, endometrial and ovarian cancer are also diagnosed and treated often in relatively younger patients in which fertility preservation is a relevant issue. The aim of this review is to highlight the correlation between therapy for female infertility and the developing cancer's risk and to describe the fertility sparing treatments in gynecological oncology.

MATERIAL AND METHODS

A systematic review of the literature through the main scientific search engines (PubMed and Google Scholar) was performed. We selected the most relevant articles based on the largest case series and the latest updates. All selected documents have been listed in the references.

RESULTS

Fifty-six relevant articles published between 1996 and 2019 were identified.Results from the available evidence report no significant increased risk of endometrial, cervical, and ovarian cancer in patients having infertility treatments.In young patients diagnosed with gynecological cancer, preservation of fertility is a personalized choice depending on several factors (type, stage, age and desire to conceive, safety of the treatment, and feasibility of fertility sparing surgery). For ovarian cancer FIGO stage IA G1, IA G2 (grade), and IC G1; for endometrial adenocarcinoma grade 1 with no lymphovascular space invasion (LVSI) or myometrial invasion and for early-stage cervical cancer (FIGO stage 2018: IA1-IB1), fertility sparing treatment is possible. The role of fertility sparing treatment with the increase of personalization of therapies therapy is always a theme of discussion and research.

CONCLUSION

At present data regarding the risk of gynecological cancers after infertility treatments are reassuring. Careful evaluation of female fertility-sparing options in young women interested by ovarian, endometrial, or cervical tumors should be carried out involving a multidisciplinary team and ensuring safety and efficacy.

Fertility treatment and cancers-the eternal conundrum: a systematic review and meta-analysis

STUDY QUESTION

Does fertility treatment (FT) significantly increase the incidence of breast, ovarian, endometrial or cervical cancer?

SUMMARY ANSWER

Overall, FT does not significantly increase the incidence of breast, ovarian or endometrial cancer and may even reduce the incidence of cervical cancer.

WHAT IS KNOWN ALREADY

Infertility affects more than 14% of couples. Infertility and nulliparity are established risk factors for endometrial, ovarian and breast cancer, yet the association with FT is more contentious.

STUDY DESIGN, SIZE, DURATION

A literature search was carried out using Cochrane Library, EMBASE, Medline and Google Scholar up to December 2019. Peer-reviewed studies stating cancer incidence (breast, ovarian, endometrial or cervical) in FT and no-FT groups were identified. Out of 128 studies identified, 29 retrospective studies fulfilled the criteria and were included (n = 21 070 337).

PARTICIPANTS/MATERIALS, SETTING, METHODS

In the final meta-analysis, 29 studies were included: breast (n = 19), ovarian (n = 19), endometrial (n = 15) and cervical (n = 13), 17 studies involved multiple cancer types and so were included in each individual cancer meta-analysis. Primary outcome of interest was cancer incidence (breast, ovarian, endometrial and cervical) in FT and no-FT groups. Secondary outcome was cancer incidence according to specific fertility drug exposure. Odds ratio (OR) and random effects model were used to demonstrate treatment effect and calculate pooled treatment effect, respectively. A meta-regression and eight sub-group analyses were performed to assess the impact of the following variables, maternal age, infertility, study size, outliers and specific FT sub-types, on cancer incidence.

MAIN RESULTS AND THE ROLE OF CHANCE

Cervical cancer incidence was significantly lower in the FT group compared with the no-FT group: OR 0.68 (95% CI 0.46-0.99). The incidences of breast (OR 0.86; 95% CI 0.73-1.01) and endometrial (OR 1.28; 95% CI 0.92-1.79) cancers were not found to be significantly different between the FT and no-FT groups. Whilst overall ovarian cancer incidence was not significantly different between the FT and no-FT groups (OR 1.19; 95% CI 0.98-1.46), separate analysis of borderline ovarian tumours (BOT) revealed a significant association (OR 1.69; 95% CI 1.27-2.25). In further sub-group analyses, ovarian cancer incidence was shown to be significantly higher in the IVF (OR 1.32; 95% CI 1.03-1.69) and clomiphene citrate (CC) treatment group (OR 1.40; 95% CI 1.10-1.77), respectively when compared with the no-FT group. Conversely, the incidences of breast (OR 0.75; 95% CI 0.61-0.92) and cervical cancer (OR 0.58; 95% CI 0.38-0.89) were significantly lower in the IVF treatment sub-group compared to the no-FT group.

LIMITATIONS, REASONS FOR CAUTION

The large, varied dataset spanning a wide study period introduced significant clinical heterogeneity. Thus, results have to be interpreted with an element of caution. Exclusion of non-English citations, unpublished work and abstracts, in order to ensure data accuracy and reliability was maintained, may have introduced a degree of selection bias.

WIDER IMPLICATIONS OF THE FINDINGS

The results for breast, ovarian, endometrial and cervical cancer are reassuring, in line with previously published meta-analyses for individual cancers but the association between IVF and CC treatment and an increase in ovarian cancer incidence requires additional work to understand the potential mechanism driving this association. In particular, focusing on (i) discriminating specific treatments effects from an inherent risk of malignancy; (ii) differential risk profiles among specific patient sub-groups (refractory treatment and obesity); and (iii) understanding the impact of FT outcomes on cancer incidence.

STUDY FUNDING/COMPETING INTEREST(S)

This study did not receive any funding. The authors have no financial, personal, intellectual and professional conflicts of interest to declare.

PROSPERO REGISTRATION NUMBER

CRD42019153404.

A Potential Pathogenic Link Between Cancer of Female Reproductive System and Infertile Women Treated With Assisted Reproduction Techniques

Prevention and treatment of infertility remains a priority for developed countries where a large proportion of women undergo in vitro fertilization (IVF) after ovarian stimulation. Latest data suggest that, in the USA alone, almost eight million women of fertile age will have sought medical advice for fertility problems by 2025. However, over the last years, attention has been increasingly focused, and questions have risen, on the long-term health effects in women who underwent assisted reproductive technologies (ARTs). Since the emergence of ART, reports highlight a possible connection of ovarian stimulation and several types of gynaecological cancer, including ovarian, endometrial and cervical types, but due to limited scientific evidence, such a speculation is still under investigation. The objective of this review is to summarize the latest data of ovarian hyperstimulation and IVF, associated with the risk of gynecological tract cancer development.

Validation of Assisted Reproductive Technology in the Medical Birth Registry of Norway Versus the Norwegian Prescription Database

BACKGROUND

Increasing attention has been given to the long-term effects of assisted reproductive technology (ART). This study assessed the validity and completeness of ART as registered in the Medical Birth Registry of Norway (MBRN) using drug prescription data from the Norwegian Prescription Database (NorPD) as reference.

METHODS

In this nationwide registry validation study, we included all pregnancies recorded in the MBRN between 2005 and 2017. We estimated sensitivity, specificity, and positive and negative predictive value (PPV and NPV) of the MBRN, using data from the NorPD as reference. We obtained the total percentage of ART pregnancies that could be identified (completeness) from both registries using the capture-recapture method. We analyzed subgroups by maternal age, gestational length, mode of ART treatment, health region, and mode of registration of ART (ART institution or birth notification form).

RESULTS

Twenty-three thousand seven hundred eighteen of a total 765,789 pregnancies were registered as ART pregnancies through the MBRN and 20,807 as ART pregnancies through the NorPD. The sensitivity of the MBRN was 85.1% (95% confidence interval [CI] = 84.7, 85.6) and the PPV was 74.7% (74.1-75.2). Sensitivity declined with increasing maternal age: 71.5% (69.4-73.7) in the age group 40-44 years, and 40.7% (22.2-59.3) in the ages above 45 years. Completeness when combining data was 96.2% (96.0-96.5).

CONCLUSIONS

Our analysis shows that, when identifying women pregnant through ART, NorPD data complemented MBRN data to obtain a more complete count of all women giving birth after ART in Norway.

Use of Fertility Drugs and Risk of Malignant Melanoma: Results from a Large Danish Population-Based Cohort Study

Fertility drugs have not definitively been linked to malignant melanoma. By the use of data from a large nationwide cohort of women aged 20.0-45.0 years and living in Denmark between January 1, 1995 and December 31, 2011, we assessed the association between the use of fertility drugs and the risk of malignant melanoma. Information on fertility status and the use of fertility drugs was obtained from the population-based Danish Infertility Cohort. Cox proportional hazard regression models were applied to estimate hazard ratios and 95% confidence intervals with adjustment for potential confounders. The study population comprised 1,330,954 women, of whom 86,231 (6.5%) were treated with fertility drugs. During a median follow-up of 21.0 years, 6,139 women were diagnosed with malignant melanoma. Compared with fertile women, women with fertility challenges who had used any fertility drugs had an increased risk of malignant melanoma (hazard ratio = 1.14; 95% confidence interval = 1.02-1.27). Furthermore, the use of specific types of fertility drugs (clomiphene, gonadotropins, human chorionic gonadotropin, gonadotropin-releasing hormone preparations, and progesterone) was also associated with an increased risk of malignant melanoma, with hazard ratios ranging between 1.09 and 1.13; however, the association did not reach statistical significance. Our findings indicate that the use of fertility drugs was associated with a modestly increased risk of malignant melanoma.

Long-Term Risk of Ovarian Cancer and Borderline Tumors After Assisted Reproductive Technology

BACKGROUND

Long-term effects of assisted reproductive technology (ART) on ovarian tumor risk are unknown.

METHODS

This nationwide cohort study comprises 30 625 women who received ovarian stimulation for ART in 1983-2000 and 9988 subfertile women not treated with ART. Incident invasive and borderline ovarian tumors were ascertained through linkage with the Netherlands Cancer Registry and the Dutch Pathology Registry until July 2018. Ovarian tumor risk in ART-treated women was compared with risks in the general population and the subfertile non-ART group. Statistical tests were 2-sided.

RESULTS

After a median follow-up of 24 years, 158 invasive and 100 borderline ovarian tumors were observed. Ovarian cancer risk in the ART group was increased compared with the general population (standardized incidence ratio [SIR] = 1.43, 95% confidence interval [CI] = 1.18 to 1.71) but not when compared with the non-ART group (age- and parity-adjusted hazard ratio [HR] = 1.02, 95% CI = 0.70 to 1.50). Risk decreased with higher parity and with a larger number of successful ART cycles (resulting in childbirth, Ptrend = .001) but was not associated with the number of unsuccessful ART cycles. Borderline ovarian tumor risk was increased in ART-treated women compared with the general population (SIR = 2.20, 95% CI = 1.66 to 2.86) and with non-ART women (HR = 1.84, 95% CI = 1.08 to 3.14). Risk did not increase with more ART cycles or longer follow-up time.

CONCLUSIONS

Increased ovarian cancer risk in ART-treated women compared with the general population is likely explained by nulliparity rather than ART treatment. The increased risk of borderline ovarian tumors after ART must be interpreted with caution because no dose-response relationship was observed.

Endocrine Risk Factors of Endometrial Cancer: Polycystic Ovary Syndrome, Oral Contraceptives, Infertility, Tamoxifen

Endometrial cancer is the most common gynecologic cancer and is predominantly endocrine-related. The role of unopposed estrogen in the development of endometrial cancer has been investigated in numerous studies. Different reproductive factors such as younger age at menarche, late age at menopause, infertility, nulliparity, age of birth of the first child, and long-term use of unopposed estrogens during hormone replacement therapy have been associated with an increased risk of endometrial cancer. In contrast, there is a growing body of evidence for a protective role of oral contraceptives. Most of the published data on the association between infertility and polycystic ovary syndrome are inconclusive, whereas the effect of tamoxifen on the risk of endometrial cancer has been well established. With this review, we aim to summarize the evidence on the association between infertility, polycystic ovary syndrome, oral contraceptives, and tamoxifen and the development of endometrial cancer.

Cancer in IVF patients treated at age 40 years and older: long term follow-up

RESEARCH QUESTION

Current knowledge of cancer risk among women who undergo IVF is based mainly on studies of women treated in their thirties, frequently with short follow-up periods. Therefore, information about cancer risk among infertile menopausal women is limited. We aimed to evaluate the risk of cancer among IVF patients treated at age 40 years and older, followed up for an extended period.

DESIGN

Historical cohort study of all IVF patients treated at the age of 40 years or older at two university-affiliated IVF units in Jerusalem, Israel, between 1994 and 2002. Data were cross-linked with the Israel National Cancer Registry to 2016. Standardized incidence ratios (SIR) and 95% confidence intervals were computed by comparing the observed number of cancer cases with the expected cancer rate in the general Israeli population adjusted for age and year of birth. In addition, Kaplan-Meier analysis was conducted to account for the length of follow-up.

RESULTS

A total of 501 patients were included in the analysis, with mean follow-up of 16.7 ± 3.7 years (range 2-22 years). Mean age at first IVF cycle was 42.3 years (±2.1). Mean number of IVF cycles was 3.2 ± 2.6 (range 1-15). Thirty-six women (7.2%) developed invasive cancer, compared with 47.2 expected cases; SIR 0.76 (95% CI 0.53 to 1.06); 22 women were diagnosed with invasive breast cancer, compared with 19.84 expected; SIR 1.11 (95% CI 0.69 to 1.68).

CONCLUSIONS

Older women undergoing IVF treatment were not significantly associated with an excess risk of cancer at long-term follow up. Further studies, however, are needed to confirm these findings.

Phosphodiesterase 8B Polymorphism rs4704397 Is Associated with Infertility in Subclinical Hypothyroid Females: A Case-Control Study

BACKGROUND

Subclinical hypothyroidism (SCH) remains largely unnoticed as a major cause of infertility due to asymptomatic. Polymorphisms of phosphodiesterase 8B gene (PDE8B) have been linked with various diseases, including female infertility. Hence, we aimed to study prevalence of SCH, in infertile females, explore association of PDE8B rs4704397 A/G and rs6885099 G/A polymorphisms with infertility in females suffering from SCH and genotype-phenotype correlation of the polymorphisms with thyroid stimulating hormone (TSH) levels in Gujarat population.

MATERIALS AND METHODS

In this retrospective study, TSH level was estimated from plasma of 230 infertile and 100 control females by enzyme-linked fluorescence immunoassay (ELFA) to find out the prevalence of SCH. Further, based on TSH levels, thyroid function test (TFT) was performed in controls and infertile females with subclinical hypothyroidism (IF-SCH). PDE8B rs4704397 and rs6885099 polymorphisms were genotyped by PCR-RFLP and ARMS-PCR, respectively in 74 controls and 60 IF-SCH females.

RESULTS

We observed i. significantly high prevalence of SCH (32%) in the infertile females, ii. significantly lower frequency of 'G' allele (P=0.006), while the frequency of 'A' allele (P<0.0001) was higher in IFSCH females, compared to the controls, for rs4704397 A/G SNP, iii. no significant difference in the genotype (P=0.214; OR=2.51; CI=0.74-8.42) and the allele frequency (P=0.129; OR=1.51; CI=0.92-2.47) of rs6885099 G/A SNP, iv) low linkage disequilibrium for the polymorphisms, v. significantly higher frequency of 'AA' haplotype (P=0.0001; OR=3.84; CI=1.86-8.01),while the 'GG' haplotype (P=0.0023; OR=0.33; CI=0.16-0.69) was significantly lower in IF-SCH females and vi. no significant difference in the TSH level of IF-SCH females with respect to the genotypes.

CONCLUSION

The present study reports an association of PDE8B rs4704397 polymorphism with infertility in SCH females. The study categorically shows a higher prevalence of SCH in infertile females of Gujarat and advocates the importance of screening for SCH in infertility management.

Ovarian cancer stem cells and targeted therapy

BACKGROUND

Ovarian cancer has the highest ratio of mortality among gynecologic malignancies. Chemotherapy is one of the most common treatment options for ovarian cancer. However, tumor relapse in patients with advanced tumor stage is still a therapeutic challenge for its clinical management.

MAIN BODY

Therefore, it is required to clarify the molecular biology and mechanisms which are involved in chemo resistance to improve the survival rate of ovarian cancer patients. Cancer stem cells (CSCs) are a sub population of tumor cells which are related to drug resistance and tumor relapse.

CONCLUSION

In the present review, we summarized the recent findings about the role of CSCs in tumor relapse and drug resistance among ovarian cancer patients. Moreover, we focused on the targeted and combinational therapeutic methods against the ovarian CSCs.

Strong Evidences of the Ovarian Carcinoma Risk in Women after IVF Treatment: A Review Article

BACKGROUND

In-vitro fertilization (IVF) has been very popular since the birth of the first "test-tube" baby. This method is the last hope and the most serious solution for couples with infertility problems. Although childbearing is a concern of many couples, it must always be noted that any method can also have disadvantages. Thus, many studies have been done on the problems encountered by this method.

METHODS

We searched for relevant articles in Pub Med, Springer, Elsevier, and Google Scholar databases, and studied more than 70 papers. Keywords used included ovarian cancer, in vitro fertilization, gonadotropin hormone, clomiphene citrate, and infertility.

RESULTS

Due to the large number of studies, high doses of the ovulation-stimulating drugs and their repeated use in this method can increase the risk of the ovarian hyper stimulation syndrome (OHSS), and ovarian cysts, which can lead to ovarian cancer. Also, an increase in the risk of developing ovarian cancer can be due to the increased duration of treatment for up to 12 months and the high doses of medications that are followed by defecation and failure of this treatment.

CONCLUSION

Due to the increase in the rates of infertility treatments and the incidence of gynecological cancers, especially ovarian cancer, this method need to be used with caution. IVF clients and candidates should be informed about potential future risks. People should be evaluated genetically for their history of ovarian cancer and be more aware of the importance of "Personalized medicine".

A Cohort Study of Breast Cancer Risk after 20 Years of Follow-Up of Women Treated with Fertility Drugs

BACKGROUND

Using a nationwide cohort of Danish women, we investigated the association between use of fertility drugs and risk of breast cancer.

METHODS

The study cohort included women ages 20 to 44 years and living in Denmark between January 1, 1995 and December 31, 2011. Information on fertility status, use of fertility drugs, breast cancer, covariates, and vital status was obtained from the Danish Infertility Cohort and various Danish national registers. Cox proportional hazard regression models were applied to estimate hazard ratios (HR) and 95% confidence intervals (CI), adjusted for potential confounders.

RESULTS

Of the 1,330,852 women included, 96,782 (7.3%) were infertile, and 20,567 (1.5%) were diagnosed with breast cancer during a median follow-up of 20.9 years. Compared with fertile women, infertile women who had used any fertility drugs did not have an increased hazard for breast cancer overall (HR = 1.02; 95% CI, 0.95-1.10), or for any of the histologic types (ductal, lobular, or mucinous) of breast cancer. Furthermore, no associations were observed between use of specific types of fertility drugs and breast cancer.

CONCLUSIONS

No convincing associations between use of fertility drugs and breast cancer were observed after two decades of follow-up.

IMPACT

Our results do not support a marked association between fertility drugs and breast cancer and are therefore reassuring for infertile women treated with fertility drugs.

Assisted reproductive technology and risk of ovarian cancer and borderline tumors in parous women: a population-based cohort study

The study aimed to investigate if assisted reproductive technology (ART) treatment or a diagnosis of infertility were associated with the risk of ovarian cancer or borderline ovarian tumors (BOT) in parous women. In a population-based register study of 1,340,097 women with a first live birth in Sweden 1982–2012, the relationship between ART treatments, infertility and incidence of ovarian cancer or BOT were investigated using Cox regression analysis. In the cohort, 38,025 women gave birth following ART, 49,208 following an infertility diagnosis but no ART and 1,252,864 without infertility diagnosis or ART. During follow-up, 991 women were diagnosed with ovarian cancer and 747 with BOT. Women who gave birth following ART had higher incidence of both ovarian cancer (adjusted hazard ratio [aHR] 2.43, 95% confidence interval [CI] 1.73–3.42) and BOT (aHR 1.91, 95% CI 1.27–2.86), compared to women without infertility. Compared to women with infertility diagnoses and non-ART births, women with ART births also had a higher incidence of ovarian cancer (aHR 1.79, 95% CI 1.18–2.71) and BOT (aHR 1.48, 95% CI 0.90–2.44). Our results suggest that women who have gone through ART have a higher risk of ovarian cancer and BOT. At least part of that risk seems to be due to the underlying infertility and not the treatment per se, since the increased risk was smaller when comparing to other infertile women. As ART treatments are becoming more common and ovarian cancer usually occur in women of advanced age, larger studies with longer follow-up are needed in order to confirm or refute our findings.

Risk of ovarian cancer in women treated with ovarian stimulating drugs for infertility

BACKGROUND

This is an updated version of the original Cochrane Review published in the Cochrane Library in 2013 (Issue 8) on the risk of ovarian cancer in women using infertility drugs when compared to the general population or to infertile women not treated. The link between fertility drugs and ovarian cancer remains controversial.

OBJECTIVES

To evaluate the risk of invasive ovarian cancer and borderline ovarian tumours in women treated with ovarian stimulating drugs for subfertility.

SEARCH METHODS

The original review included published and unpublished observational studies from 1990 to February 2013. For this update, we extended the searches from February 2013 to November 2018; we evaluated the quality of the included studies and judged the certainty of evidence by using the GRADE approach. We have reported the results in a Summary of findings table to present effect sizes across all outcome types.

SELECTION CRITERIA

In the original review and in this update, we searched for randomised controlled trials (RCTs) and non-randomised studies and case series including more than 30 participants.

DATA COLLECTION AND ANALYSIS

At least two review authors independently conducted eligibility and 'Risk of bias' assessments and extracted data. We grouped studies based on the fertility drug used for two outcomes: borderline ovarian tumours and invasive ovarian cancer. We conducted no meta-analyses due to expected methodological and clinical heterogeneity.

MAIN RESULTS

We included 13 case-control and 24 cohort studies (an additional nine new cohort and two case-control studies), which included a total of 4,684,724 women.Two cohort studies reported an increased incidence of invasive ovarian cancer in exposed subfertile women compared with unexposed women. One reported a standardised incidence ratio (SIR) of 1.19 (95% confidence interval (CI) 0.54 to 2.25) based on 17 cancer cases. The other cohort study reported a hazard ratio (HR) of 1.93 (95% CI 1.18 to 3.18), and this risk was increased in women remaining nulligravid after using clomiphene citrate (HR 2.49, 95% CI 1.30 to 4.78) versus multiparous women (HR 1.52, 95% CI 0.67 to 3.42) (very low-certainty evidence). The slight increase in ovarian cancer risk among women having between one and three cycles of in vitro fertilisation (IVF) was reported, but this was not clinically significant (P = 0.18). There was no increase in risk of invasive ovarian cancer after use of infertility drugs in women with the BRCA mutation according to one cohort and one case-control study. The certainty of evidence as assessed using GRADE was very low.For borderline ovarian tumours, one cohort study reported increased risk in exposed women with an SIR of 3.61 (95% CI 1.45 to 7.44), and this risk was greater after treatment with clomiphene citrate (SIR 7.47, 95% CI 1.54 to 21.83) based on 12 cases. In another cohort study, the risk of a borderline ovarian tumour was increased, with an HR of 4.23 (95% CI 1.25 to 14.33), for subfertile women treated with IVF compared with a non-IVF-treated group with more than one year of follow-up. A large cohort reported increased risk of borderline ovarian tumours, with HR of 2.46 (95% CI 1.20 to 5.04), and this was based on 17 cases. A significant increase in serous borderline ovarian tumours was reported in one cohort study after the use of progesterone for more than four cycles (risk ratio (RR) 2.63, 95% CI 1.04 to 6.64). A case-control study reported increased risk after clomiphene citrate was taken, with an SIR of 2.5 (95% CI 1.3 to 4.5) based on 11 cases, and another reported an increase especially after human menopausal gonadotrophin was taken (odds ratio (OR) 9.38, 95% CI 1.66 to 52.08). Another study estimated an increased risk of borderline ovarian tumour, but this estimation was based on four cases with no control reporting use of fertility drugs. The certainty of evidence as assessed using GRADE was very low.However, although some studies suggested a slight increase in risks of ovarian cancer and borderline ovarian tumour, none provided moderate- or high-certainty evidence, as summarised in the GRADE tables.

AUTHORS' CONCLUSIONS

Since the last version of this review, only a few new relevant studies have provided additional findings with supporting evidence to suggest that infertility drugs may increase the risk of ovarian cancer slightly in subfertile women treated with infertility drugs when compared to the general population or to subfertile women not treated. The risk is slightly higher in nulliparous than in multiparous women treated with infertility drugs, and for borderline ovarian tumours. However, few studies have been conducted, the number of cancers is very small, and information on the dose or type of fertility drugs used is insufficient.

Ovarian cancer in the world: epidemiology and risk factors

Aim: Ovarian cancer is one of the most common gynecologic cancers that has the highest mortality rate. Considering the fact that knowledge on the incidence, mortality of ovarian cancer, as well as its risk factors is necessary for planning and preventing complications, this study was conducted with the aim of examining the epidemiology and risk factors of ovarian cancer in the world.

Materials and methods: In order to access the articles, Medline, Web of Science Core Collection, and Scopus databases were searched from their start to the year 2018. Full-text, English observational studies that referred to various aspects of ovarian cancer were included in the study.

Results: In total, 125 articles that had been published during the years 1925–2018 were entered into the study. Ovarian cancer is the seventh most common cancer among women. Increased risk factors of cancer have led to an upward trend in the incidence of cancer around the world. In 2018, 4.4% of entire cancer-related mortality among women was attributed to ovarian cancer. Although the incidence of cancer is higher among high Human Development Index (HDI) countries, the trend of mortality rate tends to be reversing. Various factors affect the occurrence of ovarian cancer, from which genetic factor are among the most important ones. Pregnancy, lactation, and oral contraceptive pills play a role in reducing the risk of this disease.

Conclusion: This study provides significant evidence about ovarian cancer. Considering the heavy burden of ovarian cancer on women's health, preventive measures as well as health education and early detection in high risk groups of women are highly recommended. Although some risk factors cannot be changed, a focus on preventable risk factors may reduce the risk of ovarian cancer. More studies are needed to explore the role of unclear risk factors in ovarian cancer occurrence.

Long-term effect of pregnancy-related factors on the development of endometrial neoplasia: A nationwide retrospective cohort study

Objective

By identifying pregnancy-related risk factors for endometrial neoplasia, women’s risk of developing this disease after childbirth can be predicted and high-risk women can be screened for early detection.

Methods

Study data from women who gave birth in Korea in 2007 were collected from the Korea National Health Insurance (KNHI) claims database between 2007 and 2015. The adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for the development of endometrial neoplasia were estimated by multivariate Cox proportional hazards models.

Results

Data from 386,614 women were collected for this study. By 2015, 3,370 women from the initial cohort had been diagnosed with endometrial neoplasia secondary to delivery. Multivariate Cox proportional hazards regression revealed that preeclampsia (HR 1.55, 95% CI 1.29, 1.86), advanced maternal age (≥ 35; HR 1.52, 95% CI 1.39, 1.66), multifetal pregnancy (HR 1.81, 95% CI 1.46, 2.23), multiparity (HR 1.16, 95% CI 1.08, 1.24), cesarean section (HR 1.15, 95% CI 1.07, 1.23) and delivery of a large-for-gestational-age infant (HR 1.19, 95% CI 1.02, 1.39) were independent risk factors for future endometrial neoplasia. The risk for endometrial neoplasia increased as the number of risk factors increased (risk factors ≥3: HR 2.11, 95% CI 1.86–2.40).

Conclusion

This study showed that six pregnancy-related factors—advanced maternal age, multiparity, multifetal pregnancy, cesarean section, delivery of a large-for-gestational-age infant, and preeclampsia—are positively correlated with future development of endometrial neoplasia, including endometrial hyperplasia or cancer. Close observation and surveillance are warranted to enable early diagnosis of endometrial diseases, including endometrial cancer after pregnancy in high-risk women. However, due to unavailability of clinical information, many clinical/epidemiological factors can become confounders. Further research is needed on factors associated with the risk of endometrial neoplasia.

Fertility treatment is associated with multiple meningiomas and younger age at diagnosis

PURPOSE

Meningiomas are more common in females and 70-80% express the progesterone receptor, raising the possibility that high-dose exogenous estrogen/progesterone exposure, such as occurs during fertility treatments, may increase the risk of developing a meningioma. The goal of this study was to report the incidence of prior fertility treatment in a consecutive series of female meningioma patients.

METHODS

A retrospective review (2015-2018) was performed of female patients with meningioma, and those with prior fertility treatment were compared to those without fertility treatment using standard statistical methods.

RESULTS

Of 206 female patients with meningioma, 26 (12.6%) had a history of fertility treatments. Patients underwent various forms of assisted reproductive technology including: in vitro fertilization (50.0%), clomiphene with or without intrauterine insemination (34.6%), and unspecified (19.2%). Median follow up was 1.8 years. Tumors were WHO grade I (78.6%) or grade II (21.4%). Patients who underwent fertility treatments presented at significantly younger mean age compared to those who had not (51.8 vs. 57.3 years, p = 0.0135, 2-tailed T-test), and on multivariate analysis were more likely to have multiple meningiomas (OR 4.97, 95% CI 1.4-18.1, p = 0.0154) and convexity/falx meningiomas (OR 4.45, 95% CI 1.7-11.5, p = 0.0021).

CONCLUSIONS

Patients in this cohort with a history of fertility treatment were more likely to present at a younger age and have multiple and convexity/falx meningiomas, emphasizing the importance of taking estrogen/progesterone exposure history when evaluating patients with meningioma. Future clinical studies at other centers in larger populations and laboratory investigations are needed to determine the role of fertility treatment in meningioma development.

Do the Fertility Drugs Increase the Risk of Cancer? A Review Study

Aim: All over the world, many couples cannot conceive a child and have problems with pregnancy. Ovulation-inducing drugs are among the most important drugs used for the treatment of infertility. In recent years, there have been many debates about the relationship between fertility medication and cancer. Due to the lack of comprehensive study of this matter, and as understanding the relationship between the use of fertility drugs and cancer is of importance, the present study was conducted to investigate the relationship between infertility drugs and cancer in women. Materials and Methods: To determine the relationship between infertility treatment and cancer, a comprehensive search was carried out in databases such as; Medline, Web of Science Core Collection, and Scopus using keywords words; "infertility," "ovulation induction," "cancer," "infertility treatment," "ART," "tumor," "controlled ovarian stimulation," "fertility agents," and "neoplasms." Full-text, English language, and original articles were included in this study. Results: In total, 81 articles were entered into the study. The relationship between fertility medications and breast, ovary, endometrial, uterus, colon, thyroid, skin, cervical, and non-Hodgkin's lymphoma cancers were studied. Although the relationship between fertility medications and cancer is theoretically justifiable, most studies have shown that risk of cancer will not increase after fertility treatment. Conclusion: The results of this study did not show that fertility medications increase the risk of cancer among users. In summary, the relationship between infertility treatment and cancer incidence remains an open question.

Risks of ovarian, breast, and corpus uteri cancer in women treated with assisted reproductive technology in Great Britain, 1991-2010: data linkage study including 2.2 million person years of observation

OBJECTIVE

To investigate the risks of ovarian, breast, and corpus uteri cancer in women who have had assisted reproduction.

DESIGN

Large, population based, data linkage cohort study.

SETTING AND PARTICIPANTS

All women who had assisted reproduction in Great Britain, 1991-2010, as recorded by the Human Fertilisation and Embryology Authority (HFEA).

INTERVENTIONS

HFEA fertility records for cohort members were linked to national cancer registrations.

MAIN OUTCOME MEASURES

Observed first diagnosis of ovarian, breast, and corpus uteri cancer in cohort members were compared with age, sex, and period specific expectation. Standardised incidence ratios (SIRs) were calculated by use of age, sex, and period specific national incidence rates.

RESULTS

255 786 women contributed 2 257 789 person years' follow-up. No significant increased risk of corpus uteri cancer (164 cancers observed v 146.9 cancers expected; SIR 1.12, 95% confidence interval 0.95 to 1.30) was found during an average of 8.8 years' follow-up. This study found no significantly increased risks of breast cancer overall (2578 v 2641.2; SIR 0.98, 0.94 to 1.01) or invasive breast cancer (2272 v 2371.4; SIR 0.96, 0.92 to 1.00). An increased risk of in situ breast cancer (291 v 253.5; SIR 1.15, 1.02 to 1.29; absolute excess risk (AER) 1.7 cases per 100 000 person years, 95% confidence interval 0.2 to 3.2) was detected, associated with an increasing number of treatment cycles (P=0.03). There was an increased risk of ovarian cancer (405 v 291.82; SIR 1.39, 1.26 to 1.53; AER 5.0 cases per 100 000 person years, 3.3 to 6.9), both invasive (264 v 188.1; SIR 1.40, 1.24 to 1.58; AER 3.4 cases per 100 000 person years, 2.0 to 4.9) and borderline (141 v 103.7; SIR 1.36, 1.15 to 1.60; AER 1.7 cases per 100 000 person years, 0.7 to 2.8). Increased risks of ovarian tumours were limited to women with endometriosis, low parity, or both. This study found no increased risk of any ovarian tumour in women treated because of only male factor or unexplained infertility.

CONCLUSIONS

No increased risk of corpus uteri or invasive breast cancer was detected in women who had had assisted reproduction, but increased risks of in situ breast cancer and invasive and borderline ovarian tumours were found in this study. Our results suggest that ovarian tumour risks could be due to patient characteristics, rather than assisted reproduction itself, although both surveillance bias and the effect of treatment are also possibilities. Ongoing monitoring of this population is essential.

Fertility Drugs Associated with Thyroid Cancer Risk: A Systematic Review and Meta-Analysis

Associations have been demonstrated between fertility drugs and a variety of hormone-sensitive carcinomas. The purpose of this study was to determine the relationship between fertility drugs used in the treatment of female infertility and the risk of thyroid cancer. To investigate the clinical significance of fertility drugs used for the treatment of female infertility and the risk associated with thyroid cancer, we performed a literature search using PubMed, MEDLINE, the Cochrane Library, the Web of Science, and EBSCOHOST for comparative studies published any time prior to July 21, 2017. The studies included women who were treated for infertility with fertility drugs, such as clomiphene citrate, gonadotropins, or other unspecified fertility agents, which reported the incidence of thyroid cancer as the main outcome. Eight studies were included in the meta-analyses. Among women with infertility, there was a significant positive association between thyroid cancer risk and the use of fertility drugs (relative risk [RR] = 1.35; 95% confidence interval [CI] 1.12–1.64; P = 0.002). Additionally, among women with infertility, the use of clomiphene citrate was associated with an increased risk of thyroid cancer compared to women who did not use fertility drugs (RR = 1.45; 95% CI 1.12–1.88; P = 0.005). After pooling results, we found that the parity status of infertile women using fertility drugs was not associated with thyroid cancer risk (RR = 0.99; 95% CI 0.61–1.58, P = 0.95). In summary, clomiphene citrate (the most commonly used fertility drug) and other fertility drugs are associated with an increased risk of thyroid cancer.

Use of fertility medications and cancer risk: a review and update

PURPOSE OF REVIEW

There is increasing use of fertility medications for ovulation induction and ovarian stimulation for in-vitro fertilization in the treatment of female infertility. In this review, recent literature regarding the association between fertility medication and cancer risk is reviewed.

RECENT FINDINGS

Several important publications have recently addressed the relationship between use of fertility medications and cancer risk. There are methodological limitations to many of these studies, including unique challenges in studying rare cancers that often develop several years after the time of fertility medication exposure. Although infertility per se is a risk factor for some female cancers, including breast, endometrial and ovarian cancer, most studies do not show a significant risk of these cancers with the use of fertility medications. Some studies, however, have shown a possible increased relative risk of borderline ovarian cancer, although the increased absolute risk is small without a clear causal relationship.

SUMMARY

The collective data regarding the risk of developing cancer from use of fertility medications are reassuring, although several methodological issues in these studies limit definitive conclusions.

Ovarian cancer stem cells more questions than answers

Epithelial ovarian cancer is a highly lethal disease, which is usually diagnosed at a late stage with extensive metastases in the abdominal cavity. Ovarian cancer either develops from the ovarian surface epithelium (OSE) or from serous intra-epithelial carcinoma (STIC). Primary therapy consists of debulking surgery and platinum based chemotherapy. The success of debulking surgery depends on surgical skills but also on the gene signature of the tumour. Debulking surgery combined with first line platinum based chemotherapy, frequently leads to complete remission. However, most ovarian cancers relapse. Once the disease has relapsed, the interval between subsequent therapies decreases steadily due to rapid progression and therapy resistance. Research on therapy resistance of ovarian cancer is frequently devoted to genetic alterations in cancer cells, leading to drug inactivation, enhanced DNA repair mechanisms and intracellular pathway derangements. However the knowledge of ovarian cancer stem cells (OCSC) and the role they play in the development of cancer and therapy resistance is sparse. In this review current knowledge on the characteristics of OCSCs and the micro environmental mechanisms leading to the development or activation of OCSCs resulting in ovarian cancer is reviewed. Moreover the role of OCSC in both surgical and systemic therapy resistance and the relation with epithelial mesenchymal transformation (EMT) is discussed, as are micro-environmental signals leading to OCSC or EMT activation.