Knowledge, Attitudes, and Practices of Female High School Adolescents Regarding Modern Contraceptive Methods in Brazzaville in 2024

Abstract

Introduction: The objective of this study was to analyze the knowledge, attitudes, and practices of female high school adolescents in Brazzaville regarding modern contraceptive methods in 2024. Population and Methods: This was an analytical KAP (Knowledge, Attitudes, and Practices) study conducted from February 1 to July 25, 2024, including non-probabilistically selected female adolescents present in high schools who provided their assent or informed consent. The variables studied included sociodemographic, sexual, and reproductive characteristics, as well as knowledge, attitudes, and practices. Results: 400 adolescents were interviewed. The mean age was 17.1 ± 1.4 years, 57% were sexually active, 11.4% had previously experienced a pregnancy, and 69.2% had undergone an induced abortion. They demonstrated insufficient knowledge of modern contraceptive methods (78.3%), prejudicial ignorance in 15.3% of cases, with varying levels of certainty; inadequate attitudes (70%), and inadequate practices (62.9%). Analysis of associated factors revealed that insufficient knowledge level influences attitude (OR = 0.47, 95% CI = 0.282 - 0.785, p = 0.004); insufficient knowledge level influences practice (OR = 0.124, 95% CI = 0.061 - 0.25, p < 0.000001); inadequate attitude influences practice (OR = 2.848, 95% CI = 1.567 - 5.174, p = 0.001); and sexual inactivity influences the knowledge level (OR = 0.442, 95% CI = 0.256 - 0.765, p = 0.004). Conclusion: Strengthening education through the integration of a structured sexual and reproductive health education program into the school curriculum starting from the secondary level would contribute to improving contraceptive practices among female high school adolescents.

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Bialay, P. , Jostin, B. , Gabriel, O. , César, M. and Clautaire, I. (2026) Knowledge, Attitudes, and Practices of Female High School Adolescents Regarding Modern Contraceptive Methods in Brazzaville in 2024. Open Journal of Obstetrics and Gynecology, 16, 822-834. doi: 10.4236/ojog.2026.165077.

1. Introduction

Modern contraception, defined as the set of reversible methods (hormonal, mechanical, and chemical) that allow the prevention of unwanted pregnancies, is a pillar of family planning [1] [2]. It represents a major public health challenge and plays a key role in reducing maternal mortality, which remains a concerning issue in low-income countries: 346 deaths per 100,000 births, compared to only 10 in developed countries [2].

Adolescence is a critical transition phase marked by significant physical, psychological, and social changes [3]. This period is often associated with early sexual activity, with a median age of first sexual intercourse at 14 years [4]. In 2019, 21 million young girls (aged 15 - 19) became pregnant; 50% of these pregnancies were unwanted and often led to dangerous clandestine abortions [5]. This phenomenon is driven by ignorance and low utilization of modern contraceptive methods [6] [7]. In Congo, the situation is alarming: the rate of early pregnancies increases from 19.8% at age 16 to 25.9% at age 17 [8]. Despite the risks of complications and the repressive legal framework surrounding abortion, data remain poorly documented. It is in this context that we aimed to analyze the knowledge, attitudes, and practices of female high school adolescents in Brazzaville regarding modern contraceptive methods in 2024.

2. Population and Methods

This was an analytical KAP (Knowledge, Attitudes, and Practices) study conducted from February 1 to July 25, 2024 (6 months) in two public general education high schools in the city of Brazzaville, listed under the Departmental Directorate of Preschool, Primary, Secondary Education, and Literacy, namely: Nganga Édouard High School and the Revolution High School. The selection of the two high schools was motivated by their central location in the city of Brazzaville—a determining criterion, as the positioning of these two educational establishments allows them to attract students from all districts of the city, thereby ensuring a certain representativeness of adolescent girls from the entire city and not just from specific areas.

The target population consisted of female adolescents enrolled and regularly attending the aforementioned high schools during the 2023-2024 school year. Excluded were female high school adolescents with medical or psychological conditions that would make participation in the study difficult or inappropriate, as well as those who had participated in a similar study in the six months prior.

The 400 students were selected using simple random sampling. The sample size was calculated using the SCHWARTZ formula, with the modern contraceptive prevalence among adolescents estimated at 39% according to the Demographic and Health Survey EDSC2/2011-2012 in the Republic of Congo [9], increased by 10%.

The variables studied were:

  • Sociodemographic, sexual, and reproductive characteristics: age, nationality, place of residence, level of education, marital status, religion, age at first sexual intercourse, parity, induced abortion;

  • Knowledge: overall and partial knowledge;

  • Attitudes: perceptions, beliefs, and misconceptions regarding modern contraceptive methods;

  • Practices: modern contraceptives previously used, mode of use, source of supply, current use of modern contraceptives, and recourse to a health agent.

To ensure the effective implementation of the survey, a pre-test was conducted to assess the female high school adolescents’ understanding of the questionnaire. This pre-test was carried out with 5 female high school students from each grade level, randomly selected from a public high school not included in the study. This phase allowed for the adjustment of certain questions and the adaptation of the questionnaire to the comprehension level of this population.

Data analyses were performed using SPSS version 25 software.

The questionnaire was adapted from CAP (Knowledge, Attitudes, and Practices) tools published in previous studies on contraception in sub-Saharan Africa [10]-[12]. It consisted of 30 items, including 12 on knowledge, 10 on attitudes, and 8 on practices. Scoring rules and classification thresholds were defined for each domain.

The knowledge level was judged as “sufficient” when the score of correct answers was >7/14 and “insufficient” when the score of correct answers was ≤7/14.

Attitudes were judged as “appropriate” when the score of correct answers was >25/50 and “inappropriate” when the score of correct answers was ≤25/50.

Practices, for their part, were judged as “good” when the score of correct answers was >5/10 and “poor” when the score of correct answers was ≤5/10.

An analysis of the certainty level of responses was also conducted using the response quality spectrum for Instruction 1 by Dieudonné Leclercq [13]. This method categorizes knowledge questions into a spectrum where the investigator marks the given response and circles the degree of certainty or probability percentage among the following six options: 0%, 20%, 40%, 60%, 80%, 100%. If the respondent had no knowledge of the question, the investigator was required to indicate a certainty level of 0%.

Attitudes were evaluated using a Likert scale, with a predefined scale featuring the following response options: totally agree, agree, disagree, totally disagree. Practices were considered good if they met the usage norms for the various methods, and poor if they did not comply with these norms.

Pearson’s Chi-square test was used to compare percentages. Subsequently, the Odds Ratio (OR) and its 95% confidence interval (CI) were calculated; these measures were used to assess the correlation between two qualitative variables, with a p-value less than 5%.

The study received approval from the Ethics Committee of the Faculty of Health Sciences at Marien Ngouabi University. For minor participants, double consent was obtained (written assent from the adolescents and consent from the parent/legal guardian).

3. Results

3.1. Sociodemographic, Sexual, and Reproductive Characteristics (Table 1 and Table 2)

3.1.1. Evaluation of Response Certainties

The analysis of responses using Instruction 1 of Dieudonné Leclercq’s cognitive and metacognitive diagnosis allowed us to identify the following certainties:

  • Incorrect Responses (RI) = 15.3%

  • Correct Responses (RC) = 84.7%

From the RI, we detected that:

  • 12.7% of the misconceptions are harmful (8.7% of RI with maximum certainty)

  • 2.6% of the misconceptions are unusable with 0% recognized ignorance

  • The imprudence index is 3.1%

Table 1. Sociodemographic, sexual, and reproductive characteristics of female high school adolescents in Brazzaville from February 1 to June 30, 2024.

Variables

Number (n)

Percentages (%)

Age

14 - 15 years

52

13

16 - 17 years

191

48

18 - 19 years

157

39

Nationality

Congolese

378

94.5

Foreign

22

5.5

Place of Residence

Makélékélé

47

11.7

Bacongo

43

10.7

Poto-poto

29

7.2

Moungali

49

12.3

Ouenzé

77

19.3

Talangai

68

17

Mfilou

48

12

Madibou

2

0.5

Djiri

37

9.3

Level of Education

Second Year

153

38.3

Penultimate Year

91

22.7

Final Year

156

39

Table 2. Sexual and reproductive characteristics of female high school adolescents in Brazzaville from February 1 to July 30, 2024.

Variables

Number (n)

Percentages (%)

Existence of a Partner

Yes

230

57.5

No

170

42.5

Sexual Activity

Yes

228

57

No

172

43

Age at First Sexual Intercourse

10 - 15 years

94

41.2

16 - 17 years

96

42.1

18 - 19 years

38

16.7

Cumulative Partners

Only 1

157

69

2 or more

71

31

Gravidity

Nulligravida

202

88.6

Primigravida

22

9.6

Oligogravida

4

1.8

Parity

Nulliparous

218

95.6

Primiparous

9

3.9

Oligoparous

1

0.4

Induced Abortion

None

6

23.1

One

18

69.2

Two or more

2

7.7

The overall knowledge level was insufficient in 78.3% of the female high school adolescents and sufficient in the remaining 21.7%.

The graphical spectrum of incorrect responses is represented in Figure 1.

Regarding the correct responses, we detected that:

  • 58.4% of knowledge is usable;

  • 26.3% of knowledge is unusable with 7.4% recognized ignorance;

  • The confidence index is 14.1%.

Note: Vertical axis (Y-axis): Represents the percentage (%) or score of responses falling into specific spectral categories. Horizontal axis (X-axis): Represents the degree of certainty (certainty levels) or the probability percentage associated with incorrect responses, ranging from −100 to 0 (corresponding to the options: 0%, −20%, −40%, −60%, −80%, −100%).

Figure 1. Distribution of the spectral qualities of incorrect responses from female high school adolescents regarding modern contraceptive methods.

3.1.2. Evaluation of the Attitude Level

The adapted attitudes of female high school adolescents regarding modern contraceptive methods in Brazzaville from February 1 to July 30, 2024, are represented in Figure 2.

Note: Vertical axis (Y-axis): Represents the number of adolescents (n)/percentage (%) who responded to each statement regarding attitudes. Horizontal axis (X-axis): Represents the Likert scale options, numbered from 1 to 4 (corresponding to the predefined choices: strongly agree, agree, disagree, strongly disagree).

Figure 2. Representation of the adapted attitudes of female high school adolescents regarding modern contraceptive methods in Brazzaville from February 1 to July 30, 2024.

The maladapted attitudes of female high school adolescents regarding modern contraceptive methods in Brazzaville from February 1 to July 30, 2024, are represented in Figure 3.

Note: Vertical axis (Y-axis): Represents the number of adolescents (n), with a scale ranging from 0 to 200. Horizontal axis (X-axis): Represents the Likert scale options, numbered from 1 to 4 (corresponding to the predefined choices: strongly agree, agree, disagree, strongly disagree).

Figure 3. Representation of the maladapted attitudes of female high school adolescents regarding contraceptive methods in Brazzaville from February 1 to July 30, 2024.

The overall attitude level of female high school adolescents regarding modern contraceptive methods was adapted in 30% of the female high school adolescents and maladapted in the remaining 70%.

3.1.3. Evaluation of the Practice Levele

The overall practice level of female high school adolescents regarding modern contraceptive methods was good in 37.1% of the female high school adolescents and poor in the remaining 62.9% (Table 3).

Table 3. Detailed distribution of the practices of female high school adolescents regarding modern contraceptive methods in Brazzaville from February 1 to July 30, 2024.

Variables

Number (n)

Percentages (%)

Previous Use of a Modern Contraceptive

Yes

202

90.6

No

21

9.4

Type of Contraceptive Used

Condom

145

71.8

Pill

49

24.3

Implant

5

2.5

Erroneous Molecules

59

29.2

Mode of Use

Good Use

91

45

Poor Use

111

55

Source of Supply

Pharmacy

116

57.4

Health Center

6

3

ACBF

-

-

Social Circle

11

5.4

School

-

-

Shop

22

10.9

Street Vendor

79

39.1

Current Use of a Modern Contraceptive

Yes

148

73.3

No

54

26.7

Consultation with a Health Agent

Yes

30

14.9

No

172

85.1

4. Report on Influences

4.1. Influence of Sociodemographic, Sexual, and Reproductive Characteristics on Knowledge (Table 4)

The distribution of the sociodemographic, sexual, and reproductive characteristics of adolescent high school girls in Brazzaville from February 1 to July 30, 2024, is presented in Table 4.

Table 4. Distribution of the influence of sociodemographic, sexual, and reproductive characteristics of female high school adolescents on their knowledge level regarding modern contraceptive methods in Brazzaville from February 1 to July 30, 2024.

Knowledge Level

OR (IC95%)

p-value

Insufficient

Sufficient

n (%)

n (%)

Place of Residence

0.011*

Bacongo

26 (8.9)

11 (13.6)

1.382 (O.555 - 3.44)

0.487

Djiri

23 (7.9)

12 (14.8)

1.704 (0.688 - 4.219)

0.249

Madibou

-

0.999

Makélékélé

39 (13.4)

7 (8.6)

0.586 (0.218 - 1.579)

0.291

Mfilou

35 (12)

11 (13.6)

1.027 (0.421 - 2.502)

0.954

Moungali

27 (9.2)

15 (18.5)

1.815 (0.771 - 4.272)

0.172

Ouenzé

65 (22.3)

8 (9.9)

0.402 (0.158 - 1.024)

0.056

Poto-Poto

26 (8.9)

2 (2.5)

0.251 (0.053 - 1.184)

0.081

Talangai

49 (16.8)

15 (18.5)

Have you ever had sexual intercourse?

0.003*

No

129 (44.2)

21 (25.9)

0.442 (0.256 - 0.765)

0.004

Yes

163 (55.8)

60 (74.1)

Number of Partners

0.049*

Only 1

236 (80.8)

73 (90.1)

2.165 (0.987 - 4.751)

0.054

2 or more

56 (19.2)

8 (9.9)

4.2. Influence of Knowledge and Attitudes on Practices (Table 5)

The distribution of the influence of knowledge and attitude levels of adolescent high school girls on their practices regarding modern contraception in Brazzaville from February 1 to July 30, 2024, is presented in Table 5.

Table 5. Distribution of the influence of the knowledge level and attitudes of female high school adolescents on their practices regarding modern contraception in Brazzaville from February 1 to July 30, 2024.

Variables

Practice

OR (IC 95%)

p-value

Poor

Good

n (%)

n (%)

Knowledge

Insufficient

112 (88.2)

36 (48.0)

0.124 (0.061 - 0.25)

<0.000001

Sufficient

15 (11.8)

39 (52.0)

-

-

Attitudes

Maladapted

92 (72.4)

36 (48.0)

2.848 (1.567 - 5.174)

0.001

Adapted

35 (27.6)

39 (52.0)

-

-

Total

127 (100)

75 (100)

5. Discussion

Our study was conducted only in two public general education high schools, selected through reasoned choice. Consequently, although the results are relevant, they cannot be generalized to all female high school adolescents in the city of Brazzaville, nor to those in other departments.

The female high school adolescents were aged 14 to 19 years, with a mean age of 17.1 ± 1.4 years. Dramé et al. in Guinea Conakry in 2023 [14] reported similar findings, where the mean age was 17.3 years.

More than half of the participants were sexually active. Oko et al. in Congo Brazzaville had already reported in 2024 a high prevalence of early sexual intercourse at 72.7% [15]. We attribute this proportional difference to the heterogeneity (boys and girls) of the population selected by the authors.

Although Congolese society is pro-natalist, this does not apply to adolescents, as seen in our study. The majority of those who had previously been pregnant had already undergone at least one clandestine abortion, thereby exposing them to the risk of serious complications [16] [17].

These facts highlight, on the one hand, the undesirability of early pregnancies [18]-[21]; and on the other hand, a lack of knowledge about modern contraceptive methods [20].

In order to adopt good contraceptive practices, the female high school adolescents in Brazzaville need to acquire knowledge on the subject. The overall analysis of their knowledge revealed that 78.3% of the adolescents had an insufficient knowledge level regarding modern contraceptive methods. Nearly identical conclusions, with 86% of cases, were drawn by Mbou Essié et al. in 2018 [22], whose population consisted of postpartum women in the same region. The absence of teaching modules on sexual and reproductive health in secondary schools, as well as sociocultural barriers to the use of contraceptive methods, are the causes [8]. These observations contrast sharply with those reported by Debuo et al. in 2023 in Ghana, where 78.5% of high school girls had an adequate knowledge level regarding modern contraceptive methods, explained by the existence of several sensitization campaigns on modern contraceptives that had a significant influence on the entire population, particularly students [23].

In our study, the distribution of RI (Incorrect Responses) takes the form of a steep J-shaped curve to the left; this is concerning, as 8.7% of the 15.3% incorrect responses from the female high school adolescents were given with maximum certainty (100%), and it is noted that 12.7% of the misconceptions are harmful. These harmful misconceptions, spanning all the questions, suggest the need for educational reinforcement by integrating a structured sexual and reproductive health education program into the school curriculum starting from secondary level, with interactive sessions including educational games, debates, and simulations to strengthen learning.

However, we noted that the Imprudence index, or the average certainty accompanying incorrect responses, at 3.1% here, was reassuring because it is low.

Regarding correct responses, it would be desirable for their distribution on the graphical spectrum to have its peak as far to the right as possible (also a J-shaped curve). This is the case in our study, where the curve takes a steep J-shape to the right, which is satisfactory. It is observed that 58.4% of the knowledge is usable, including 29.9% perfect responses (correct with 100% certainty), 18.9% doubtful responses (correct with 20% and 40% certainty), and 7.4% admitted ignorance. The Confidence index, or the average certainty accompanying correct responses, is 14.1%, which is very low.

The Confidence and Imprudence indices are impact indicators that will serve as references in evaluating knowledge after the educational reinforcement of the school curriculum with the structured sexual and reproductive health education program.

In our context, the overall attitudes were predominantly maladapted. This result reflects the existence of erroneous beliefs, misconceptions, or reluctance to use modern contraceptive methods. Our results are comparable to those of Ramathuba et al. in South Africa [20], who reported that 63% of adolescents exhibited a negative attitude toward modern contraceptives. These authors justify these results by the presence of prejudices related to religion and morality, which consider the use of contraceptives as reprehensible and conducive to premarital sexual relations.

The female high school adolescents mostly had poor contraceptive practices. Dramé et al. [14] found a proportion of 99% of female students with a poor level of contraceptive practices, underscoring the importance of persistent barriers to the effective use of modern contraceptive methods in African contexts.

The influence of insufficient knowledge on attitudes and practices aligns with the conclusions of Ramathuba et al. [24], according to which the information deficit remains one of the major determinants of risky contraceptive behaviors in sub-Saharan Africa.

6. Conclusion

Female high school adolescents are predominantly nulligravid and sexually active. They exhibit insufficient knowledge, maladaptive attitudes, and poor contraceptive practices. This finding underscores the major influence of the knowledge level on attitudes and behaviors, calling for reinforcement of reproductive health education, as well as facilitated access to services adapted to their needs.

Conflicts of Interest

There is no conflict of interest.

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