To assess the knowledge women of reproductive age have about contraceptive methods and identify factors influencing both knowledge and method selection.
DesignDescriptive, analytical, cross-sectional, observational study, conducted between November 2024 and April 2025.
SettingCommunity and primary healthcare level in Portugal, particularly in the central region.
Participants490 women aged 15–49 living in Portugal. Inclusion: menstruated. Recruitment was via social media and health centers. No dropouts were recorded.
Main measuresKnowledge of contraceptive methods, method usage and influencing factors, assessed via a structured, validated questionnaire.
ResultsThe most known methods were the pill and male condom. Only 24.3% correctly identified the most effective methods. Regarding STI protection, 91.6% answered correctly. Most used methods were the pill and male condom. Safety and effectiveness were the most valued criteria. Medical advice was highly influential. Statistically significant associations were found between sociodemographic factors and knowledge/choice.
ConclusionsDespite high general knowledge, gaps remain regarding effectiveness. Educational strategies and counseling, especially during family planning consultations, are essential to improve contraceptive literacy and reduce unplanned pregnancies.
Evaluar el conocimiento de las mujeres en edad reproductiva sobre los métodos anticonceptivos, e identificar los factores que influyen en el conocimiento y la elección del método.
DiseñoEstudio observacional, descriptivo, analítico y transversal, realizado entre noviembre de 2024 y abril de 2025.
LocalizaciónComunidad y atención primaria en Portugal, especialmente en la región centro.
ParticipantesCuatrocientas noventa mujeres entre 15 y 49 años, residentes en Portugal. Inclusión: haber menstruado. Reclutamiento vía redes sociales y centros de salud. No hubo abandonos.
Principales medidasConocimiento sobre métodos anticonceptivos, uso y factores de elección, evaluado mediante cuestionario estructurado validado.
ResultadosLos métodos más conocidos fueron la píldora y el preservativo masculino. Solo el 24,3% identificó correctamente los métodos más eficaces. El 91,6% respondió correctamente sobre la protección frente a ITS. Los métodos más usados fueron la píldora y el preservativo masculino. Seguridad y eficacia fueron los criterios más valorados. La opinión médica fue muy influyente. Hubo asociaciones estadísticamente significativas entre factores sociodemográficos y conocimiento/uso.
ConclusionesAunque el conocimiento general es elevado, persisten lagunas sobre la eficacia. Las estrategias educativas y la orientación personalizada en consultas de planificación familiar son claves para mejorar la alfabetización en anticoncepción y prevenir embarazos no deseados.
Sexual and reproductive health represents a fundamental pillar of human rights and public health. It is recognized as a state of physical, emotional, mental, and social well-being in relation to sexuality.1
Family planning, as a key component of this domain, allows women and couples to freely decide the number of children they wish to have and the spacing between them. This reduces the number of unintended pregnancies and, consequently, the number of abortions as well as maternal and infant mortality. It also helps prevent sexually transmitted infections (STIs) and empowers women.2,3
Globally, in 2023, 257 million women of reproductive age still had an unmet need for contraception. The reasons for this include limited access to contraceptive methods, restricted method choices, fear or experience of adverse effects, cultural, religious, or gender-related barriers, and poor quality of available services.2
In Portugal, the prevalence of modern contraceptive use in Portugal is 78%. However, 7% of Portuguese women report unmet contraceptive needs, and sources of information on contraception should be improved.4
Furthermore, there is still a significant number of unplanned pregnancies, potentially associated with this lack of information, the low frequency of family planning and/or gynecological consultations, or the incorrect use of the chosen method. In 2023, voluntary terminations of pregnancy within the first 10 weeks accounted for approximately 96.7% of all abortions that year, corresponding to 16,559 procedures.5
In this context, health literacy plays a crucial role. Defined as the ability to access, understand, evaluate, and use information and services in ways that promote and maintain health and well-being,6 sexual and reproductive health literacy directly influences behaviors related to sexuality.
There are various methods with different efficacy rates, classified as reversible or irreversible. Reversible methods include non-hormonal (such as behavioral – calendar method, Billings method, withdrawal –, barrier methods – male and female condoms, diaphragm –, and local chemical methods such as spermicides), hormonal (such as oral pills, vaginal rings, injectables, transdermal systems, subcutaneous implants, and emergency contraception), and long-acting reversible contraceptives (LARC) – including the copper intrauterine device (IUD) and the levonorgestrel-releasing intrauterine system (LNG-IUS). Irreversible methods include female sterilization (tubal ligation) and male sterilization (vasectomy).
Among these, subcutaneous implants, IUDs, sterilization, and hormonal methods are the most effective when used correctly.7 Thus, healthcare professionals play an important role in helping individuals choose a method that is both effective and aligned with their needs.
Cultural and institutional barriers still limit women's autonomy, stressing the need for empathetic and unbiased counseling.8
Although some studies in Portugal have explored sexual and reproductive health literacy, particularly in relation to different contraceptive methods, they present several limitations. For example, the study by Louro et al. (2017)9 surveyed only adolescents. The study by Mouro et al. (2023)10 assessed the risks and benefits of only one method. Finally, the study by Cunha et al. (2019)11 examined factors influencing method choice, but the sample size was small and limited to only two municipalities.
Therefore, this study aimed to assess the knowledge that women of reproductive age have regarding contraceptive methods and the factors that influence their choice. As a secondary objective, it sought to evaluate potential factors that influence contraceptive knowledge.
Materials and methodsThis cross-sectional study took place from November 2024 to April 2025. Inclusion criteria: women aged 15–49, residing in Portugal; exclusion criteria: no menarche.
Data collection was carried out using a questionnaire comprising four sections: (1) six questions on sociodemographic and clinical data; (2) seven questions on knowledge about contraceptive methods; (3) eight questions on contraceptive use; and (4) nineteen questions on factors influencing method choice (Appendix A). The questions were adapted from two previous studies: Louro et al. (2017)9 and Cunha et al. (2019).11 The questionnaire was disseminated online and in health centers in the central region of Portugal. Informed consent was obtained from all participants.
Data were analyzed using IBM SPSS Statistics, version 30.0.0. Descriptive and inferential statistics were conducted using Chi-square and Mann–Whitney U tests, due to non-normal distribution of numerical variables. A significance level of p<0.05 was adopted.
For the analysis of knowledge regarding the most effective contraceptive methods, correct answers were considered those identifying the following: subcutaneous implant, vasectomy, LNG-IUS, bilateral tubal ligation, copper IUD, injectables, transdermal system, oral pill, and vaginal ring.
For methods protecting against STIs, correct answers included only male and/or female condoms.
Ethical approval was obtained from the Ethics Committee of the Faculty of Medicine of the University of Coimbra.
General outline of the study: Flow of participant selection in a cross-sectional observational study. Questionnaires were disseminated online and in primary care centers. Inclusion criteria included women aged 15–49 that lived in Portugal and already had menstruated. Thirteen ineligible responses were excluded, resulting in a final sample of 490 women.
Results
The sample included 490 women residing in Portugal, aged between 15 and 49 years, with the majority residing in the central region of the country (62.9%) (Table 1).
Region, educational level, field of study/work, and marital status of the women.
| Category | Subcategory | Frequency (n=490) | Percentage (%) |
|---|---|---|---|
| Region | North | 145 | 29.6% |
| Center | 308 | 62.9% | |
| South | 23 | 4.7% | |
| Islands | 14 | 2.8% | |
| Educational level | ≤9th grade | 21 | 4.3% |
| 12th grade | 111 | 22.7% | |
| Bachelor's degree | 227 | 46.3% | |
| Master's degree | 126 | 25.7% | |
| Doctorate | 2 | 0.4% | |
| Other | 3 | 0.6% | |
| Field of study/work | Science and Technology | 101 | 20.6% |
| Humanities | 58 | 11.8% | |
| Economics | 28 | 5.7% | |
| Arts | 16 | 3.3% | |
| Health | 247 | 50.4% | |
| Education | 12 | 2.4% | |
| Other | 28 | 5.7% | |
| Marital status | Single, not in a relationship | 182 | 37.1% |
| Single, in a relationship | 247 | 50.4% | |
| Married | 52 | 10.6% | |
| Divorced | 3 | 0.6% | |
| Widowed | 1 | 0.2% | |
| Civil union | 5 | 1.0% | |
The mean age of participants was 25.3±7.1 years. Approximately half of the respondents were studying or working in the health field (50.4%) (Table 1).
The average age of menarche was 12.3±1.4 years. Roughly half of the participants reported being in a relationship (50.4%) (Table 1).
All respondents were familiar with the concept of contraceptive methods. The most well-known methods were the female pill (99.0%), male condom (98.4%), and copper IUD (94.3%). The least known were the transdermal system (48.0%), spermicide (52.7%), and LNG-IUS (55.7%). These same methods were also the most frequently recognized as methods that prevent pregnancy (Table 2).
Most well-known contraceptive methods, those considered to prevent pregnancy, most effective for pregnancy prevention, and those considered to prevent STIs.
| Contraceptive method | Aware of the method (%) | Considers it prevents pregnancy (%) | Most effective for pregnancy prevention (%) | Considers it prevents STIs (%) |
|---|---|---|---|---|
| Tubal ligation | 87.8% | 83.7% | 73.7% | 0.6% |
| Vasectomy | 87.3% | 82.9% | 73.5% | 0.8% |
| Male condom | 98.4% | 94.9% | 69.8% | 98.0% |
| Copper IUD | 94.3% | 90.4% | 65.9% | 0.4% |
| Female pill | 99.0% | 92.4% | 64.3% | 0.8% |
| Implant | 83.7% | 75.5% | 47.1% | 0.2% |
| LNG-IUS | 55.7% | 61.2% | 39.8% | 0.4% |
| Female condom | 90.0% | 87.3% | 36.1% | 80.6% |
| Vaginal ring | 89.2% | 77.3% | 31.2% | 2.9% |
| Injectable | 58.4% | 53.7% | 19.8% | 0.2% |
| Transdermal patch | 48.0% | 50.6% | 16.5% | 0.2% |
| Emergency contraception pill | 90.6% | 58.0% | 14.3% | 0.4% |
| Diaphragm | 60.4% | 51.6% | 4.1% | 3.5% |
| Spermicide | 52.7% | 41.2% | 1.8% | 0.8% |
| Natural methods | 63.9% | 29.6% | 1.2% | 0.2% |
IUD, intrauterine device; LNG-IUS, Levonorgestrel-releasing intrauterine system; STI, sexually transmitted infections.
Regarding the most effective contraceptive methods, only 24.3% of respondents answered correctly. A significant majority incorrectly believed that the male condom is among the most effective methods for pregnancy prevention (69.8%) (Table 2).
In terms of STI protection, 91.6% of respondents correctly identified the appropriate methods (Table 2).
Regarding usage, 93.1% of participants had used at least one contraceptive method in their lifetime. The most commonly used methods were the female pill (79.4%) and the male condom (75.5%). Around 17.6% of participants reported having used emergency contraception (Table 3).
Most used contraceptive methods and factors influencing their choice.
| Contraceptive method | Frequency (n=490) | Percentage (%) |
|---|---|---|
| Female pill | 389 | 79.4% |
| Male condom | 370 | 75.5% |
| Emergency contraception pill | 86 | 17.6% |
| Vaginal ring | 66 | 13.5% |
| Natural methods | 59 | 12.0% |
| Female condom | 35 | 7.1% |
| Copper IUD | 27 | 5.5% |
| Implant | 25 | 5.1% |
| LNG-IUS | 8 | 1.6% |
| Tubal ligation | 3 | 0.6% |
| Diaphragm | 3 | 0.6% |
| Injectable | 1 | 0.2% |
| Transdermal patch | 1 | 0.2% |
| Spermicide | 1 | 0.2% |
| Vasectomy | 0 | 0% |
| Factor | 1 – Not important (%) | 2 – Slightly important (%) | 3 – Moderately important (%) | 4 – Very important (%) |
|---|---|---|---|---|
| Safety | 0% | 0.4% | 4.3% | 95.3% |
| Effectiveness | 0% | 0.4% | 5.3% | 94.3% |
| Ease of use | 0.4% | 4.5% | 26.1% | 69.0% |
| Duration | 2.4% | 12.9% | 32.4% | 52.2% |
| Cost | 5.1% | 16.3% | 34.9% | 43.7% |
| Accessibility | 1.4% | 5.9% | 31.0% | 61.6% |
| Side effects | 0.8% | 4.1% | 28.4% | 66.7% |
| STI protection | 3.3% | 5.7% | 18.6% | 72.4% |
| Preventing irregular bleeding | 8.4% | 14.5% | 30.0% | 47.1% |
| Maintaining monthly menstruation | 17.1% | 17.1% | 24.9% | 40.8% |
| Acne reduction | 16.7% | 22.9% | 27.6% | 32.9% |
| Menstrual pain relief | 9.4% | 14.7% | 25.9% | 50.0% |
| Doctor's opinion | 4.1% | 10.0% | 31.4% | 54.5% |
| Pharmacist's opinion | 31.0% | 24.9% | 24.3% | 19.8% |
| Family's opinion | 48.0% | 28.6% | 14.3% | 9.2% |
| Partner's opinion | 24.5% | 24.9% | 33.7% | 16.9% |
| Friends’ opinion | 55.1% | 28.0% | 11.8% | 5.1% |
| Influencers/bloggers’ opinion | 82.0% | 11.4% | 3.5% | 3.1% |
| Religious opinion | 81.8% | 10.8% | 3.9% | 3.5% |
IUD, intrauterine device; LNG-IUS, Levonorgestrel-releasing intrauterine system; STI, sexually transmitted infections.
In terms of recommendation sources for contraceptive method use, the primary advisors were gynecologists (47.4%) and general practitioners (35.5%) (Appendix B).
When asked about the factors influencing their choice of contraceptive method, the most important were safety (95.3%) and effectiveness (94.3%), followed by STI protection (72.4%). Most participants considered medical opinion to be very important (54.5%) (Table 3).
Factors influencing knowledge about contraceptive methodsThe relationships between region, education level, field of study/work, marital status, age, and knowledge of the most effective contraceptive methods for preventing pregnancy and STIs were evaluated.
A statistically significant association was found between marital status and knowledge of the most effective contraceptive methods for pregnancy prevention (p=0.005), showing that those in romantic relationships had a higher percentage of correct answers (Appendix C). Age was also significantly associated (p<0.001), with older participants answering more accurately. No statistically significant associations were found between region, education level, or field of study/work and knowledge of the most effective methods for pregnancy prevention (Table 4).
Relationship between knowledge of the most effective contraceptive methods for preventing pregnancy and STIs, and region, education, field of study/work, marital status, and age.
| Category | Subcategory | Correct – pregnancy (%) | p | Correct – STIs (%) | p |
|---|---|---|---|---|---|
| Region | North | 24.8% (n=36) | 0.983a | 93.8% (n=136) | 0.404a |
| Center | 24.4% (n=75) | 90.3% (n=278) | |||
| South | 21.7% (n=5) | 91.3% (n=21) | |||
| Islands | 21.4% (n=3) | 100.0% (n=14) | |||
| Educational level | ≤9th grade | 23.8% (n=5) | 0.955a | 81.0% (n=17) | 0.002a |
| 12th grade | 26.1% (n=29) | 89.2% (n=99) | |||
| Bachelor's degree | 24.2% (n=55) | 93.8% (n=213) | |||
| Master's degree | 23.0% (n=29) | 92.9% (n=117) | |||
| Doctorate | 0.0% (n=0) | 100.0% (n=2) | |||
| Other | 33.3% (n=1) | 33.3% (n=1) | |||
| Field of study/work | Science and Technology | 23.8% (n=24) | 0.104a | 93.1% (n=94) | 0.041a |
| Humanities | 12.1% (n=7) | 79.3% (n=46) | |||
| Economics | 39.3% (n=11) | 92.9% (n=26) | |||
| Arts | 25.0% (n=4) | 93.8% (n=15) | |||
| Health | 24.7% (n=61) | 93.5% (n=231) | |||
| Education | 16.7% (n=2) | 91.7% (n=11) | |||
| Other | 35.7% (n=10) | 92.9% (n=26) | |||
| Marital status | Single, not in a relationship | 19.8% (n=36) | 0.005a | 90.7% (n=165) | 0.935a |
| Single, in a relationship | 24.7% (n=61) | 92.3% (n=228) | |||
| Married | 32.7% (n=17) | 90.4% (n=47) | |||
| Divorced | 0.0% (n=0) | 100.0% (n=3) | |||
| Widowed | 100.0% (n=1) | 100.0% (n=1) | |||
| Civil union | 80.0% (n=4) | 100.0% (n=5) | |||
Regarding knowledge about methods that protect against STIs, a statistically significant association was found with education level (p=0.002), where higher education levels correlated with more correct responses (Appendix D); with field of study/work (p=0.041), where “Science and Technology” and “Health” showed higher rates of correct answers (Appendix E); and with age (p=0.035), again showing that older participants had better knowledge. No significant relationship was found with region or marital status (Table 4).
Factors influencing the choice of contraceptive methodThe relationship between region, education level, field of study/work, marital status, age, age at menarche, and the choice of specific contraceptive methods was assessed.
A statistically significant association was found between the use of male condoms and marital status (p=0.018), with “single women in a relationship” being the group that used them most (Appendix F), and with age (p=0.003), with older women using them more frequently. Female condom use was significantly associated with field of study (p=0.024), being more frequently used by those in the health field (Appendix G).
Spermicide use was significantly associated with education level (p<0.001), being more common among individuals with lower educational attainment (Appendix H). Female pill use was significantly associated with region (p=0.030), with lower usage in the islands (Appendix I), and with marital status (p=0.025), where “single women in a relationship” were the most frequent users (Appendix J).
The transdermal system was significantly associated with marital status (p=0.005), being used exclusively by married women (Appendix K). Implant use was associated with region (p=0.006), being more prevalent in the central region (Appendix L).
IUD use was significantly associated with field of study (p<0.001), with “Arts” and “Economics” showing the lowest usage rates (Appendix M), marital status (p<0.001), with women in romantic relationships using it more (Appendix N), and age (p<0.001), with older women showing higher usage.
Tubal ligation was significantly associated with marital status (p<0.001), occurring only among married women (Appendix O), and with age (p=0.007), showing higher use among older participants. The remaining methods did not show significant associations with any variable (Tables 5 and 6).
Factors influencing the choice of contraceptive method.
| Category | Subcategory | Natural methods% (n) | p | Male condom% (n) | p | Female condom% (n) | p | Diaphragm% (n) | p | Spermicide% (n) | p | Female pill % (n) | p | Ring% (n) | p | Injectable% (n) | p |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Region | North (n=145) | 2.8% (4) | 0.282a | 29.7% (43) | 0.664a | 2.1% (3) | 0.836a | 0.0% (0) | 0.756a | 0.7% (1) | 0.497a | 63.4% (92) | 0.030a | 6.2% (9) | 0.471a | 0.0% (0) | 0.898a |
| Center (n=308) | 2.3% (7) | 29.5% (91) | 2.3% (7) | 0.6% (2) | 0.0% (0) | 52.6% (162) | 6.8% (21) | 0.3% (1) | |||||||||
| South (n=23) | 8.7% (2) | 17.4% (4) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 52.2% (12) | 13.0% (3) | 0.0% (0) | |||||||||
| Islands (n=14) | 0.0% (0) | 28.6% (4) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 28.6 (4) | 14.3% (2) | 0.0% (0) | |||||||||
| Educational level | ≤ 9th grade (n=21) | 4.8% (1) | 0.967a | 23.8% (5) | 0.871a | 0.0% (0) | 0.833a | 0.0% (0) | 0.960a | 4.8% (1) | <0.001a | 33.3% (7) | 0.213a | 4.8% (1) | 0.869a | 0.0% (0) | 0.949a |
| 12th grade (n=111) | 1.8% (2) | 32.4% (36) | 3.6% (4) | 0.0% (0) | 0.0% (0) | 58.6% (65) | 6.3% (7) | 0.0% (0) | |||||||||
| Bachelor's degree (n=227) | 2.6% (6) | 28.2% (64) | 1.8% (4) | 0.4% (1) | 0.0% (0) | 56.4% (128) | 6.6% (15) | 0.4% (1) | |||||||||
| Master's degree (n=126) | 3.2% (4) | 28.6% (36) | 1.6% (2) | 0.8% (1) | 0.0% (0) | 53.2% (67) | 9.5% (12) | 0.0% (0) | |||||||||
| Doctorate (n=2) | 100.0% (2) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 100.0% (2) | 0.0% (0) | 0.0% (0) | |||||||||
| Other (n=3) | 0.0% (0) | 33.3% (1) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 33.3% (1) | 0.0% (0) | 0.0% (0) | |||||||||
| Field of study/work | Science and Technology (n=101) | 1.0% (1) | 0.102a | 33.7% (34) | 0.121a | 1.0% (1) | 0.024a | 0.0% (0) | 0.922a | 0.0% (0) | 0.986a | 58.4% (59) | 0.434a | 4.0% (4) | 0.076a | 0.0% (0) | 0.986a |
| Humanities (n=58) | 1.7% (1) | 31.0% (18) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 48.3% (28) | 8.6% (5) | 0.0% (0) | |||||||||
| Economics (n=28) | 0.0% (0) | 21.4% (6) | 3.6% (1) | 0.0% (0) | 0.0% (0) | 42.9% (12) | 10.7% (3) | 0.0% (0) | |||||||||
| Arts (n=16) | 12.5% (2) | 50% (8) | 6.3% (1) | 0.0% (0) | 0.0% (0) | 37.5% (6) | 25% (4) | 0.0% (0) | |||||||||
| Health (n=247) | 2.8% (7) | 28.3% (70) | 1.6% (4) | 0.8% (2) | 0.4% (1) | 57.5% (142) | 7.3% (18) | 0.4% (1) | |||||||||
| Education (n=12) | 0.0% (0) | 25% (3) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 58.3% (7) | 0.0% (0) | 0.0% (0) | |||||||||
| Other (n=28) | 7.1% (2) | 10.7% (3) | 10.7% (3) | 0.0% (0) | 0.0% (0) | 57.1% (16) | 3.6% (1) | 0.0% (0) | |||||||||
| Marital status | Single, not in a relationship (n=182) | 0.5% (1) | 0.117a | 24.7% (45) | 0.018a | 1.1% (2) | 0.845a | 0.5% (1) | 0.997a | 0.0% (0) | 0.964a | 50% (91) | 0.025a | 6.0% (11) | 0.177a | 0.0% (0) | 0.132a |
| Single, in a relationship (n=247) | 3.2% (8) | 35.6% (88) | 2.4% (6) | 0.4% (1) | 0.4% (1) | 62.3% (154) | 9.3% (23) | 0.0% (0) | |||||||||
| Married (n=52) | 7.7% (4) | 13.5% (7) | 3.8% (2) | 0.0% (0) | 0.0% (0) | 42.3% (22) | 0.0% (0) | 1.9% (1) | |||||||||
| Divorced (n=3) | 0.0% (0) | 33.3% (1) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 33.3% (1) | 0.0% (0) | 0.0% (0) | |||||||||
| Widowed (n=1) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | |||||||||
| Civil union (n=5) | 0.0% (0) | 20.0% (1) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 40% (2) | 20% (1) | 0.0% (0) |
| Median (IQR) | p | Median (IQR) | p | Median (IQR) | p | Median (IQR) | p | Median (IQR) | p | Median (IQR) | p | Median (IQR) | p | Median (IQR) | p | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Age | ||||||||||||||||
| Uses | 24 (10) | 0.290b | 23 (4) | 0.003b | 23.5 (11) | 0.673b | 28.5 | 0.622b | 19 | 0.134b | 23 (4) | 0.092b | 23 (4) | 0.482b | 28 | 0.246b |
| Does not use | 23 (4) | 23 (4) | 23 (4) | 23 (4) | 23 (4) | 23 (5) | 23 (4) | 23 (4) | ||||||||
| Age at menarche | ||||||||||||||||
| Uses | 12 (1) | 0.470b | 12 (2) | 0.621b | 13 (1) | 0.247b | 12 (0) | 0.726b | 9 | 0.083b | 12 (2) | 0.978b | 12 (1) | 0.755b | 12 | 0.804b |
| Does not use | 12 (2) | 12 (2) | 12 (2) | 12 (2) | 12 (2) | 12 (2) | 12 (2) | 12 (2) | ||||||||
Factors influencing the choice of contraceptive method (continued).
| Category | Subcategory | Transdermal patch% (n) | p | Implant% (n) | p | Copper IUD% (n) | p | LNG-IUS% (n) | p | Tubal ligation% (n) | p | Vasectomy% (n) | p | Emergency contraception pill% (n) | p |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Region | North (n=145) | 0.0% (0) | 0.756a | 0.7% (1) | 0.006a | 3.4% (5) | 0.735a | 0.7% (1) | 0.934a | 0.0% (0) | 0.618a | 0.0% (0) | 0.898a | 0.0% (0) | 0.898a |
| Center (n=308) | 0.6% (2) | 1.9% (6) | 3.2% (10) | 1.0% (3) | 1.0% (3) | 0.3% (1) | 0.3% (1) | ||||||||
| South (n=23) | 0.0% (0) | 4.4% (1) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | ||||||||
| Islands (n=14) | 0.0% (0) | 14.3% (2) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | ||||||||
| Educational level | ≤ 9th grade (n=21) | 0.0% (0) | 0.936a | 4.8% (1) | 0.956a | 4.8% (1) | 0.855a | 0.0% (0) | 0.852a | 4.8% (1) | 0.180a | 0.0% (0) | 0.949a | 0.0% (0) | 0.635a |
| 12th grade (n=111) | 0.9% (1) | 1.8% (2) | 2.7% (3) | 0.9% (1) | 0.9% (1) | 0.0% (0) | 0.9% (1) | ||||||||
| Bachelor's degree (n=227) | 0.4% (1) | 1.8% (4) | 4.0% (9) | 1.3% (3) | 0.0% (0) | 0.4% (1) | 0.0% (0) | ||||||||
| Master's degree (n=126) | 0.0% (0) | 2.4% (3) | 1.6% (2) | 0.0% (0) | 0.8% (1) | 0.0% (0) | 0.0% (0) | ||||||||
| Doctorate (n=2) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | ||||||||
| Other (n=3) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | ||||||||
| Field of study/work | Science and Technology (n=101) | 0.0% (0) | 0.255a | 3.0% (3) | 0.923a | 4.0% (4) | <0.001a | 1.0% (1) | 0.971a | 0.0% (0) | 0.385a | 1.0% (1) | 0.696a | 0.0% (0) | 0.986a |
| Humanities (n=58) | 0.0% (0) | 1.7% (1) | 5.2% (3) | 1.7% (1) | 1.7% (1) | 0.0% (0) | 0.0% (0) | ||||||||
| Economics (n=28) | 3.6% (1) | 0.0% (0) | 3.6% (1) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | ||||||||
| Arts (n=16) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | ||||||||
| Health (n=247) | 0.4% (1) | 2.0% (5) | 1.6% (4) | 0.8% (2) | 0.4% (1) | 0.0% (0) | 0.4% (1) | ||||||||
| Education (n=12) | 0.0% (0) | 0.0% (0) | 25% (3) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | ||||||||
| Other (n=28) | 0.0% (0) | 3.6% (1) | 0.0% (0) | 0.0% (0) | 3.6% (1) | 0.0% (0) | 0.0% (0) | ||||||||
| Marital status | Single, not in a relationship (n=182) | 0.0% (0) | 0.005a | 1.6% (3) | 0.991a | 0.5% (1) | <0.001a | 0.5% (1) | 0.950a | 0.0% (0) | <0.001a | 0.0% (0) | 0.964a | 0.5% (1) | 0.889a |
| Single, in a relationship (n=247) | 0.0% (0) | 2.4% (6) | 2.4% (6) | 1.2% (3) | 0.0% (0) | 0.4% (1) | 0.0% (0) | ||||||||
| Married (n=52) | 3.8% (2) | 1.9% (1) | 13.5% (7) | 0.0% (0) | 5.8% (3) | 0.0% (0) | 0.0% (0) | ||||||||
| Divorced (n=3) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | ||||||||
| Widowed (n=1) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | ||||||||
| Civil union (n=5) | 0.0% (0) | 0.0% (0) | 20% (1) | 0.0% (0) | 0.0% (0) | 0.0% (0) | 0.0% (0) | ||||||||
| Median (IQR) | p | Median (IQR) | p | Median (IQR) | p | Median (IQR) | p | Median (IQR) | p | Median (IQR) | p | Median (IQR) | p | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Age | ||||||||||||||
| Uses | 36.5 | 0.051b | 24 (5) | 0.185b | 31 (20) | <0.001b | 24 (0) | 0.388b | 48 | 0.007b | 19 | 0.134b | 20 | 0.202b |
| Does not use | 23 (4) | 23 (4) | 23 (4) | 23 (4) | 23 (4) | 23 (4) | 23 (4) | |||||||
| Age at menarche | ||||||||||||||
| Uses | 12 (0) | 0.726b | 12.5 (2) | 0.728b | 12 (2) | 0.959b | 11.5 (1) | 0.154b | 12 | 0.871b | 9 | 0.083b | 13 | 0.437b |
| Does not use | 12 (2) | 12 (2) | 12 (2) | 12 (2) | 12 (2) | 12 (2) | 12 (2) | |||||||
Findings revealed that the most well-known contraceptive methods were the pill (99%) and the male condom (98.4%). These results align with those from Louro et al. (2017), which focused on Portuguese adolescents and found similar levels of knowledge (98.9% and 97.1%, respectively).9 However, the third most recognized method differed: in Louro's study, it was the female condom (87.7%), while in the present study it was the copper IUD (94.3%). This may be due to the older age group in this study.
The most frequently used methods were also the pill and male condom, consistent with trends observed in various countries globally.12
The data also highlighted that knowledge and usage of long-acting reversible contraceptives (LARC) remain limited, with the LNG-IUS being the least recognized method. This trend is supported by several studies, including Moreau et al. (2013)13 and Hall et al. (2016), which reported that lack of awareness was a primary reason for not using LARC.14 However, these findings contrast with the Nest-C study, which showed that the IUD was the second most used method in Portugal in 2021.15
The low prevalence of use for certain methods, such as the LNG-IUS, the transdermal system, or spermicides, may be due to the fact that these are often not discussed during family planning consultations. This was evident in the study by Dehlendorf et al. (2014), which found that many healthcare providers only addressed methods already mentioned by patients.16 Moreover, these methods may not be subsidized or freely available in public health centers, as shown in Sorgi et al. (2019), where 72.11% of women cited high cost as a reason for not using LARC.17
It is also worth considering that the term “intrauterine system” (IUS) may not be widely recognized, as this method is often referred as “IUD,” potentially leading to underreporting.
The most frequently cited factors influencing contraceptive choice were safety and effectiveness, consistent with findings from Cunha et al. (2019)11 and D'Souza et al. (2022).18 This is particularly relevant given that only 24.3% of women correctly identified the most effective methods. Existing literature highlights an overestimation of the effectiveness of the male condom in preventing pregnancy, also observed in Louro et al. (2017)9 and in participants of “The Contraceptive CHOICE Project”.19 This apparent contradiction reflects a gap between theoretical value placed on effectiveness and actual knowledge, suggesting that decisions may be influenced by misconceptions.
Regarding STI prevention, 91.6% of women correctly identified the appropriate methods, showing a slight improvement over Louro et al. (2017) (89.5%),9 possibly due to the older age group in this study. This factor was also considered “very important” by 72.4% of respondents, significantly higher than the 54.3% reported in Cunha et al. (2019).11 However, the data also indicated that condom use is most prevalent among older and in a relationship, suggesting that younger women may be less cautious in STI prevention.
The influence of third-party opinions was notable: 85.9% of women considered the doctor's opinion “important” or “very important”. These figures align with Cunha et al. (2019) (86.7%).11 As healthcare professionals, particularly gynecologists (47.4%) and family doctors (35.5%), are the main sources of information, it is crucial to ensure they are equipped to provide accurate and up-to-date contraceptive counseling.
Age significantly influenced both knowledge and the use of certain contraceptive methods, with older women more likely to choose the IUD or sterilization. This may reflect different reproductive needs and more frequent contact with healthcare services, especially for family planning or gynecological care, which enhances access to information.
Marital status also showed significant differences, with married women more likely to choose sterilization, possibly because they have completed their reproductive plans and benefit from stable relationships and access to definitive procedures.
The study also showed that higher education levels and working/studying in health-related fields were associated with better knowledge of STI-preventive methods. This is expected, as academic and professional environments facilitate access to accurate information and scientific terminology. However, this did not translate into greater knowledge of method effectiveness, indicating persistent gaps even among those in healthcare.
Thus, there is a pressing need to improve sexual health literacy. This should begin in adolescence and be addressed not only in clinical settings but also in schools and communities, including within health-related academic programs. Public campaigns, validated digital content, educational sessions in schools, and peer education initiatives could help fill existing gaps. These interventions must be tailored to different educational levels and age groups. Ongoing professional development for healthcare providers is also essential to ensure contraceptive counseling is unbiased, current, and inclusive of all available options.
Improving sexual and reproductive health literacy will contribute to reducing unplanned pregnancies,2 which continue to account for most pregnancy terminations in Portugal.5 Furthermore, it responds more effectively to unmet contraceptive needs, which continue to affect approximately 7% of women of reproductive age in the country.4
This study's limitations include the use of a convenience sample, limiting the generalizability of findings. The high proportion of participants from healthcare (50.4%) may have skewed the results toward higher levels of knowledge than those found in the general population. Since data were self-reported, recall bias or social desirability bias may be present. The questionnaire was not pre-validated.
These results point to the need for further investigation into the knowledge and factors influencing contraceptive use in Portugal. A nationally representative sample would allow for generalization to the wider population and improve comparisons across demographic groups.
Qualitative methods, such as interviews or focus groups, could help explore the reasons behind knowledge gaps, misconceptions about effectiveness, and persistent myths. This approach could also clarify real-life decision-making criteria and the role of trust in information sources.
Given the recognized influence of medical opinions on contraceptive choices, it is essential to investigate counseling practices among Portuguese healthcare professionals, to understand which methods are most commonly recommended or omitted, and what factors influence these decisions (e.g., training, personal preferences, time constraints, biases).
Finally, the development and evaluation of specific educational interventions, tailored to different age groups and literacy levels, are recommended to improve contraceptive knowledge, dispel myths, and promote informed choices. Their effectiveness could be assessed through intervention studies with pre- and post-testing, possibly integrated into schools, health centers, and digital platforms.
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Despite the free availability of contraceptive methods in Portugal, knowledge gaps and unmet contraceptive needs persist.
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Many women base their contraceptive choices on perception rather than clinical effectiveness.
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Previous studies focused on specific age groups or methods, lacking broader population insight.
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Provides updated data on contraceptive knowledge and use among a diverse sample of Portuguese women aged 15–49.
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Identifies the most valued factors in method choice (safety, effectiveness, medical opinion).
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Demonstrates significant associations between sociodemographic factors and both contraceptive knowledge and method use.
The study received approval from the Ethics Committee of the Faculty of Medicine, University of Coimbra. Informed consent was obtained from all participants. Data were handled anonymously and confidentially.
FundingThis study did not receive any public or private funding.
Conflict of interestThere are no conflicts of interest to declare.
The followings are the supplementary data to this article:
