Título

ORIGINAL ARTICLE

JOURNAL OF THE FACULTY OF HUMAN MEDICINE 2020 - Universidad Ricardo Palma
DOI 10.25176/RFMH.v20i2.2840

RISK FACTORS FOR INFERTILITY IN WOMEN IN A PERUVIAN HOSPITAL

FACTORES DE RIESGO PARA INFERTILIDAD EN MUJERES EN UN HOSPITAL PERUANO

Sheyla B. Villanueva-Ccoyllo1, Luis Roldan-Arbieto2

1Hospital Vitarte, Lima - Perú.
2Escuela de Postgrado en Gestión Pública de la Universidad Tecnológica del Perú, Lima - Perú.

ABSTRACT

Introduction: We can define infertility as the failure to achieve pregnancy after 12 months of unprotected sex, according to the World Health Organization (WHO). Between 60 to 80 million couples annually suffer from this problem. In Peru, there are no updated reports that allow knowing these figures. In addition, few studies allow knowing the causes of this condition Objective: To determine the risk factors associated with infertility in female patients treated in outpatient offices in the Gynecology Service of the Vitarte Hospital, period January 2015 to April 2019. Methods: We conducted an observational, analytical, retrospective case-control study, considering a sample of 82 cases and 82 controls. Clinical, demographic and habits of harmful consumption factors were considered and, to measure the association, the crude and adjusted odds ratios were used, for which the statistical package SPSS was used. Results: Based on the adjusted OR, dyspareunia was identified (OR: 4.16, 95% CI 1.56-11.14), dysmenorrhea, (OR: 4.22, 95% CI 1.79-9.93), pelvic inflammatory disease (OR: 5.59, 95% CI 2.11-14.84), and alcohol consumption (OR: 2.87, 95% CI 1.10-7.49), as statistically significant risk factors for the development of infertility. Conclusion: The factors associated with infertility in the gynecology service of the Vitarte Hospital during the period from January 2015 to April 2019 are dyspareunia, dysmenorrhea, the history of pelvic inflammatory disease and alcohol consumption.
Key words: Infertility; Pelvic Inflammatory Disease; Ectopic pregnancy (source: MeSH NLM).

RESUMEN

Introducción: La infertilidad se define como el no logro del embarazo posterior a 12 meses de relaciones sexuales sin protección, según la Organización Mundial de la Salud (OMS). Entre 60 a 80 millones de parejas anualmente sufren este problema. En el Perú no existen reportes actualizados que permitan conocer estas cifras y hay pocos estudios que permitan conocer las causas de esta afección. Objetivo: Determinar los factores asociados a infertilidad en pacientes mujeres atendidas en consultorios externos en el Servicio de Ginecología del Hospital Vitarte, periodo enero 2015 a abril del 2019. Métodos: Se realizó un estudio observacional, analítico, retrospectivo de casos y controles, considerando una muestra de 82 casos y 82 controles. Se consideraron factores asociados clínico, demográfico y de hábitos de consumo nocivo y, para medir la asociación, se utilizó los odds ratio crudos y ajustados, para lo cual se usó el paquete estadístico SPSS. Resultados: En base a los OR ajustados, se identificó a la dispareunia (OR:4.16, IC95% 1.56- 11.14), dismenorrea, (OR:4.22, IC95% 1.79-9.93), enfermedad pélvica infamatoria (OR:5.59, IC95% 2.11- 14.84), y el consumo de alcohol (OR:2.87, IC95% 1.10-7.49), como factores asociados estadísticamente significativos para el desarrollo de infertilidad. Conclusión: Los factores asociados a la infertilidad en el servicio de ginecología del Hospital Vitarte durante el periodo de enero 2015 a abril 2019 son la dispareunia, dismenorrea, el antecedente de enfermedad pélvica inflamatoria y, el consumo de alcohol.
Palabras clave: Infertilidad, Enfermedad Inflamatoria Pélvica, embarazo ectópico (fuente : DeCS BIREME).

INTRODUCTION

We can define infertility as couple inability, whether one of them or both, to conceive naturally in a certain period. According to American Society for Reproductive Medicine (ASRM)(1), female infertility occurs within a period of 12 months or more in women under 35 years old, or within a period of 6 months in women over 35 years old. Its etiology may be primary when the inability of achieving a spontaneous gestation occurs since the beginning of relationships without contraceptives. Or, it may be secondary, when the inability of achieving a spontaneous gestation occurs after a conception(2).

The WHO exhorts to consider infertility as a worldwide health problem(3). Fifteen percent of couples of reproductive age are infertile, worldwide. This represents from 60 to 80 million of infertile couples(3). In Latin America, we notice high rates of secondary infertility. We can explain this due to sexual and reproductive health(4). In Peru, we suspect that the situation is very similar, but there are not any updated reports that allow knowing the number of couples affected with this problem. A 2013 study reported that 4% of women between 15 and 49 years old are infertile, but it did not consider men(5,6).

Factors that lead to infertility are not clearly known. Studies performed in Asia, Latin America and Middle East reveal that the main factors that predispose to infertility are: pelvic factor 35% (includes prior tubal disease and endometriosis), male factor with abnormalities in sperm production 40%, cervical factor 7.5%, and with no known cause 5%(7-10). Besides, in the last years, women have had a change in their outlook on life, thus, they postpone their motherhood due to career goals and evolution in work(11). Regarding this, we carried out the present study, aiming to determine factors associated: demographic, clinical and habits of harmful consumption, associated to female infertility.

METHODS

We conducted an observational, analytical, retrospective case-control stud. We obtained data through reviewing medical records and applying one data collection sheet. This sheet recorded information about demographic aspects, medical history and habits of harmful consumption, which we treated with confidentiality and approval of ethics committees from the hospital and university.

Every women from 18 to 50 years old, who attended gynecology service at Vitarte Hospital for female infertility between January 2015 and April 2019, composed study population. We excluded patients with a history of hysterectomy or bilateral tubular occlusion. Also, patients whose couple has been diagnosed as infertile.

We selected a random simple sample for cases and controls groups. Regarding cases, we included those women with diagnosis of infertility. In controls, we included those women who did not have diagnosis of infertility and puerperal ones.

We registered data collected on a Excel sheet and we analyzed them applying statistical software SPSS 23, considering a significance level of 95%. We employed frequency tables and descriptive statistics.

RESULTS

We reviewed 184 medical records of women who attended to gynecology service from Vitarte Hospital. 82 of them with diagnosis of infertility and 82 without this diagnosis or puerperal ones. Regarding general features: patients from 35 to 50 years old represent 60.9% of total of the cases group’s total. Average age of cases was 35.17 (s=4.96) and of controls, 30.4 (s=6.31). Patients with secondary school completed or higher education represent 75.6% of all cases. Likewise, of all cases, 34.1% presented dyspareunia, 74.4% showed dysmenorrhea, 46.3% submitted pelvic inflammatory disease, 18.3% had ectopic pregnancy and 25.6% showed endometriosis. In addition, 65.9% consume caffeine, 12.2% use tobacco, 39% drink alcohol and 29.3% use pharmaceuticals. See Table 1.

Table 1. General features of female assisted patients at Gynecology Service at Vitarte Hospital because of female infertility.

Factors Infertility (cases) No infertility (controles) Total
  n % n % n %
Age            
>35 – 50 years 50 60.9% 22 26.82% 72 43.90%
≤ 35 years 32 47.6% 60 73.17% 92 56.09%
Media (DE)   35.17 (4.96) 30.4  (6.31)    
Level of education            
Incomplete secondary 20 24.4% 32 39.0% 51 31.70%
Complete secondary or higher education 62 75.6% 50 61.0% 113 68.30%
Dyspareunia            
Yes 28 34.1% 12 14.6% 40 24.4%
No 54 65.9% 70 85.4% 124 75.6%
Dysmenorrhea            
Yes 61 74.4% 33 40.2% 94 57.3%
No 21 25.6% 49 59.8% 70 42.7%
PID            
Yes 38 46.3% 11 13.4% 49 29.9%
No 44 53.7% 71 86.6% 115 70.1%
Ectopic            
Yes 15 18.3% 1 1.2% 16 9.8%
No 67 81.7% 81 98.8% 148 90.2%
Endometriosis            
Yes 21 25.6% 23 28.0% 44 26.8%
No 61 74.4% 59 72.0% 120 73.2%
Caffeine            
Yes 54 65.9% 43 52.4% 97 59.1%
No 28 34.1% 39 47.6% 67 40.9%
Tobacco            
Yes 10 12.2% 2 2.4% 12 7.3%
No 72 87.8% 80 97.6% 152 92.7%
Alcohol            
Yes 32 39.0% 14 17.1% 46 28.0%
No 50 61.0% 68 82.9% 118 72.0%
Pharmaceuticals            
Yes 24 29.3% 15 18.3% 39 23.8%
No 58 70.7% 67 81.7% 125 76.2%
Total 82 100.0% 82 100.0% 164 100.0%


We noted that the factors associated were maternal age over 35 years old; dyspareunia, dysmenorrhea; history of pelvic inflammatory disease; alcohol consumption. Although, it is true that we found statistically significant association with ectopic pregnancy, described by a p value <0.01, we do not consider it a risk factor associated to infertility due to low amount of sample from patients. We can observe this in so wide confidence interval (95%) that ranges from 2.33 to 140.8. The same happens with tobacco use: it has a p value = 0.02, and a risk quantified by an OR 5.56 and a confidence interval (95%) that ranges from 1.18 to 26.2. In a similar way, we display adjusted OR, result of the binary logistic regression model. In this one, we identified as factors statistically significant for infertility development the following ones: dyspareunia (OR: 5.64, CI95% 2.01- 17.32), dysmenorrhea (OR: 8.55, CI95% 3.44-23.77), pelvic inflammatory disease (OR: 10.07, CI95% 3.75- 30.75) and alcohol consumption (OR: 4.39, CI95% 1.64-12.67). (Table 2) (Figure 1).

Table 2. Factors associated to infertility in patients treated in Gynecology Service at Vitarte Hospital.

Factors associated   P value/1 OR OR CI95% Adjusted OR Adjusted OR CI95%
Age >35 – 50 years old 0.001 4.21 2.11-8.38 3.56 1.44-9.32
≤ 35 years old          
Level of education Incomplete secondary 0.064 0.53 0.27-1.04 0.35 0.13-0.88
Complete secondary or higher education          
History of Dyspareunia Yes 0.004 4.16 1.40-6.49 5.64 2.01-17.32
No          
Hystory of Dysmenorrhea Yes 0.001 4.21 2.22-8.37 8.55 3.44-23.77
No          
History of Pelvic inflammatory disease Yes <0.01 5.57 2.58-12.03 10.07 3.75-30.75
No          
History of Ectopic pregnancy/2 Yes <0.01 18.13 2.33 -140.8 - -
No          
History of Endometriosis Yes 0.6 0.83 0.41-1.65 0.79 0.29-2.15
No          
Caffeine consumption Yes 0.11 1.66 0.88-3.12 2.05 0.87-5.03
No          
Tobacco use/2 Yes 0.016 5.56 1.18- 26.2 - -
No          
Use of pharmaceuticals Yes 0.1 1.84 0.88-3.85 1.27 0.47-3.51
No          
Alcohol consumption Yes 0.002 3.1 1.50-6.42 4.39 1.64-12.67
No          
/1 Level of significance obtained through chi square of association.
/2 Due to low simple for its calculation, we omitted it from the logistic regression model and, only for-profit, we show raw OR.

Figure 1. Adjusted Odds Ratio for infertility in patients treated in Gynecology Service at Vitarte Hospital.



DISCUSSION

This study has great relevance in both clinical-practical field and theoretical field, since because of this we have better vision regarding determinants associated to infertility. We discovered significant association in women over 35 years old. Similar result to research by Ramos et al(12) with OR = 1.9, CI 95%: 1.3-4.1, p<0.001 and research by Cabrera(13) who also found association between these two variables. Martínez(14) determined that 67% of people with infertility were between 30 and 39 years old. Likewise, Malo and Marín(15) identified that age was a risk factor associated to infertility given by a p value <0.05. Finally, Toledo(16) in his study established that patients who most attended to examination were 39-year-old women. Regarding level of education, we did not statistically significant association in our sample. However, He X et al(17) in their study identified that high level of education was a protector factor in women with infertility (OR = 0.522, IC 95%: 0.391-0.696). Moreover, Toledo(16) states that most women who attended to examination due to infertility had a complete academic level. On the other side, we discovered statistically significant association with dyspareunia. These results confirm the findings by HE X(17), who also identified association with these two variables (OR = 2.447, CI 95%: 1.201-4.986). Mayhuasca(18) did not find any association between dyspareunia and infertility in his retrospective descriptive study. In addition, we discovered statistically significant association between dysmenorrhea and infertility. We confirm this thanks to the study by Mallikarjuna et al(19) with a (OR: 6.08, p=0.009). HE X(17) on his own, also discovered association with this factor (OR = 1.62). Furthermore, history of pelvic inflammatory disease turned out to be statistically significant in our study, confirming the findings by HE X(17) who also identified an association between these two variables with (OR =7.07, IC95% 3.4-14.46). Ramos et al(12) found out that it was not statistically significant with a p value over 0.05. Martínez(13) reported a 23% incidence as well as Benavides(20) who stated a 19% incidence. This contrasts our results, which suggest in our group of cases a 49% incidence. Regarding ectopic pregnancy, although we discovered statistically significant association, this may have been due to few sample of patients with this history. This is reflected in the so wide confidence interval. Safarinnejad et al(21) discovered association with ectopic pregnancy (OR= 2.45; CI 95%: 1.90–3.44; p = 0.04). Thounneau(22) found out association given by a OR: 9.9. Roa Huapaya(23) also identified association with this factor with a risk quantified by OR: 2.59. History of endometriosis resulted non-significant with infertility, in contrast with the findings by Franco et al(24). According to their study, one of the diseases associated to female infertility with higher incidence was endometriosis with a 43.4%. Roa Huapaya(23) discovered association given by a (OR: 4.1). Mayhuasca(18) found out association with a p minor than 0.05. Caffeine consumption is not statistically significant, confirming with studies by Soylu et al(12), who discovered that regular coffee portions were not a risk (OR: 1.00; IC: 0.97 – 1.03). Ramos et al(12), on their own, confirm our results stating that caffeine is not associated to infertility. Lyngsø et al(26), in their study, did not find out any association between caffeine consumption and infertility. However, caffeine consumption increases miscarriage according to daily intake. In our study, alcohol consumption is statistically significant. Greenlee et al(27) studied associated factors of female infertility in 322 cases and 322 controls, mentioning association between alcohol consumption and infertility with (OR= 1.8 IC 95% 1.2- 16.3%). Contrasting with research by Ramos et al(11), who discovered that there is not any statistically significant association between alcohol consumption and infertility, given by p values over 0.05. Although, we found statistically significant association with tobacco use, this was due to a few sample of patients regarding tobacco use. Thus, we appreciate a confidence interval so wide, which we should improve performing more studies that calculate an accurate sample size. Moreover, Greenlee et al’s(27) study did not find out statistically significant association between tobacco use and infertility (OR= 1.6 IC 95% 0.9-2.9). Use of pharmaceuticals is not statistically significant unlike study by He X et al(17), who discovered association with history of drug treatment (OR= 23.57, IC 95%: 12.32-45.10). Benito(29) reports that pharmaceuticals possibly related to sterility are numerous, such as, anti-inflammatories, chemotherapeutic, hormones, antibiotics, and others like, caffeine, chlortetracycline, dapsone, phenothiazines, nifedipine, cimetidine, cyclosporine or spironolactone. We could recommend try to avoid its use in patients with difficulty conceiving, unless it is strictly necessary. Nevertheless, we should consider that sometimes it could be the case of a patient with underlying disease. We recommend that health service professionals register the age of the couple, since it also represents an associated factor according to the literature. At the methodological level, we suggest validating these results in other sample populations and considering associated factors such as ectopic pregnancy and tobacco use, in order to guarantee an accurate representation and results that are more precise.

We state that limitations of this research are the fact that patients who attend due to infertility are referred to a more complex center that has a specialized service of infertility for further studies. There were also medical records with missing information, which did not embrace the total of factors to evaluate.

CONCLUSIONS

In the study, we identified dyspareunia, dysmenorrhea, history of pelvic inflammatory disease, and alcohol consumption as significant risk factors for infertility.

We did not find out statistically significant association between age, level of education, ectopic pregnancy, endometriosis, tobacco use and use of pharmaceuticals with infertility.

Authorship contributions: The authors participated in the genesis of the idea, project design, data collection and interpretation, analysis of results and preparation of the manuscript of this research work.
Financing: Self-financed
Conflict of interest: The authors declare that they have no conflict of interest in the publication of this article.
Received: March 5, 2020
Approved: March 19, 2020


Correspondence: Sheyla Briggith Villanueva Ccoyllo.
Address: Av. 27 de noviembre Mz C lot 22, San Juan de Miraflores.
Telephone: +51 994 340 175
Email: sheyla.villanueva.c@gmail.com

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