Article Information

Corresponding author: Yenesew Fentahun Gebrie

Article Type : Research Article

Volume : 3

Issue : 6

Received Date : 25 Jul ,2022


Accepted Date : 09 Aug ,2022

Published Date : 16 Aug ,2022


DOI : https://doi.org/10.38207/JCMPHR/2022/OCT03060174

Citation: Gebrie YF, Dessie TM, Yeshiwas D (2022) Incidence and predictors of Pregnancy among HIV Positive women on ART in North West Ethiopia: A Retrospective Cohort Study. J Comm Med and Pub Health Rep 3(06): https://doi.org/10.38207/JCMPHR/2022/OCT03060174

Copyright: © 2022 Yenesew Fentahun Gebrie. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are
  Incidence and predictors of Pregnancy among HIV Positive women on ART in North West Ethiopia: A Retrospective Cohort Study

Yenesew Fentahun Gebrie1*, Tadesse Mihretie Dessie2, Dawit Yeshiwas1

1Department of Statistics, Debre Markos University, Debre Markos, Ethiopia

2Department of Applied Human Nutrition, Marie Stopes International, Ethiopia

*Corresponding Author: Yenesew Fentahun Gebrie, Department of Statistics, Debre Markos University, Debre Markos, Ethiopia.

Abstract
Objective
: The objective of this study was to identify the prevalence and significant factors of incidence of pregnancy among HIV-positive women under ART follow-up.

Methods: A retrospective cohort study was employed and a sample size of 429 was selected using a simple random sampling technique. Both chi-square test of association and multiple binary logistic regression analysis was used.

Results: The study has shown that 21.2 % of women were pregnant during the follow-up. Variables like WHO clinical stage, spouse’s HIV status, marital status, contraception use, body weight, occupation, CD4 count, age, and time of ART were significant predictors of incidence of pregnancy.

Conclusion: Women with advanced WHO clinical stages were less likely to be pregnant. Women, who are married, employed, and had never used contraceptive methods were more likely to have pregnant. When CD4 cell count and body weight increase, the incidence of pregnancy also increases and women who had a longer time on ART were more likely to be pregnant.
Health institutions and clinicians should be cautious when the patients have faced advanced WHO clinical stage and low CD4 count. We would like to put remarks on increasing the employment of HIV Positive women, providing effective services of ART health care, and studying further investigation for the general wellbeing of mothers and their respective potentially born children.

Keywords: Antiretroviral Therapy, Binary logistic regression, Incidence of Pregnancy

Introduction
HIV is the most serious disease that humankind has ever faced, and it is a social dilemma as well. It becomes one of the world’s most serious health and development challenges for women under productive age [1]. In 2020, an estimated 37.7 million people were living with HIV worldwide, and 27.5 million people were receiving HIV treatment in the year. In 2020, nearly three-fourths (73 %) of all people living with HIV were receiving life-saving antiretroviral therapy, and 85 % of pregnant women living with HIV had access to antiretroviral treatments to prevent transmission of HIV to their child. In 2020, about 680,000 death were recorded due to AIDS-related illnesses, which is a great declination compared with death in 2010 (1.3 million) worldwide. Out of the global number of pregnant women, 83 % were living with HIV and 68 % of them were receiving life-saving antiretroviral therapy in 2020. Two-thirds (67 %) of sub-Saharan African people were living with HIV in 2020 [2].

In Ethiopia, 690,000 people were living with HIV and 65 % of them were on treatment in 2018. This year, 92 % of pregnant women with HIV received ART to prevent the disease’s mother-to-child transmission during pregnancy and to the mothers’ health.

In Ethiopia, seven regions and two administrative cities have HIV prevalence above one percent. In the regions, the prevalence of HIV was highest in Gambella (4.8 %), followed by Addis Ababa (3.4 %), Dire Dawa (2.5 %), and Harari (2.4 %) [3]. For HIV/AIDS infected women, significantly ameliorated having HIV-negative children by increasing the accessibility of ART; because, it has the potential to decrease the risk of HIV transmission from mother to child and prevents AIDS-related illness and death [4]. However, HIV-positive women are not volunteering to have the pregnancy and they are frightened to get HIV-negative children. Hence, it is significant to identify the prevalence and significant predictors of incidence of pregnancy under ART follow-up. So far, in different areas of the world, studies were conducted including in Ethiopia. However, most of the studies were done using descriptive statistics, and studies conducted in different parts of Ethiopia were not addressing the problem. Hence it is mandatory to conduct studies on the area under discussion. The study aimed to assess the prevalence and predictors of incidence of pregnancy among HIV-positive women under ART follow-up in Finote Selam general hospital.

Method
Description of the Study Area

The study was conducted at Finote Selam General Hospital, which is located in Finote Selam City administration, capital of west Gojjam zone, Amhara Region, Ethiopia. The town is located at about 387 km far from Addis Ababa and 173 km far from Bahir Dar Capital city of Amhara national regional state, Ethiopia. This hospital is the only general hospital in West Gojjam Zone that provides ART services for people living with HIV in the area of rural and urban surrounding the hospital.

Study Design and Data sources
A four-year institution-based retrospective cohort study was employed from October 2016 to September 2019 based on secondary data from medical charts of the ART clinic of the hospital.
The sources of data were HIV-positive women under ART follow-up in the Hospital. The data included all HIV-positive women under the follow-up of ART those who are aged between 15 and 49 years at the ART clinic of the hospital.

Variables in the Study
The response variable of the study was the incidence of pregnancy of HIV-positive women under ART follow-up (pregnancy occurred = 1, pregnancy not occurred =0).
The independent variables included in this study were age, educational level, occupation, marital status, religion, place of residence, child alive of women before ART follow-up, contraceptive use, WHO clinical stage, co-infection, body weight, time on ART follow-up, CD4 count and Spouse HIV status of women.

Sample Size Determination and Sampling Technique
In the research, the sample size is the core element, and it can be determined based on the following constraints: the objective of the research, design of the research, cost constraint, and degree of precision required. Considering these things, the sample size was determined using the following formula:

 

 

 

Where n is the required sample size, Z = 1.96 from a standard normal distribution, the degree of precision, d is 0.04, and the proportion of success (P) is 0.5. Based on these values the final required sample was 429.

A simple random sampling technique was employed to select these 429 sample women from the ATR clinic for a total record of patient women in the given time frame.

Method of Data Collection
Secondary data was used and a structured data collection checklist was prepared in English to extract data from the records. Data were extracted from the main excel record and patient cards of the hospital. The data was collected by the data clerk of the ART clinic and health professionals of the hospital working on the ART database.

Statistical Analysis
The data were extracted from the medical chart of HIV-positive women and checked for completeness. After checking consistency and completeness, data were coded and analyzed using SPSS version 20 software. Descriptive statistics were used to assess the prevalence of incidence of pregnancy and to see the percentage of independent variables. Both chi-square test and binary logistic regression analysis were employed. A Chi-square test was used to identify the rough association between dependent and independent variables. Lastly, multiple binary logistic regression analysis was used to identify the significant variables for the incidence of pregnancy. The strength of association was interpreted using an odds ratio with a 95 % confidence interval; because the logistic regression model has a powerful analytic tool for medical research of the regression coefficients as log odds [5]. When odds ratio is the ratio of the probability of the occurrence of an event to the non-occurrence of an event [6]. From the result of multiple logistic regression analysis, variables with a P-value of ≤ 0.05 were considered significant predictors of incidence of pregnancy for HIV-positive women.

Ethical Approval and Informed Consent
This study received ethical approval from the institutional review board of Finote Selam general hospital. All study participants were informed that they have full right not to participate in the study or to stop the interview at any time they wish if that was their choice. All patients provided written informed consent before enrollment in the study.

Results
General characteristics
The objective of this study was to assess the prevalence and to identify the important predictors of incidence of pregnancy of women on ART follow-up. Of the total (n=429) sample women, 91 (21.2 %) were pregnant during the study time. The result showed that mothers who are under WHO stage I, stage II, stage III, and stage VI were 101 (23.5 %), 156 (36.4 %), 120 (28.0 %), and 52 (12.1 %), respectively.
More than half (n=225, 52.4 %) of HIV-positive women were married and most (n=384, 89.5 %) of the women were live in the urban area.

Out of the total sample, about 160 (37.3 %) and 118 (27.5 %) reported their level of education as primary and secondary respectively. Nearly half (n=209, 48.7 %) of the respondents reported that their time duration in ART follow-up was less than 25 months. Furthermore, more than one-third (n= 160, 37.3 %) of women were unemployed and 271 (63.2 %) of women had children alive before ART follow-up (Table 1). Before multiple logistic regression analysis, the chi-square test of association was made to identify the rough association between the incidence of pregnancy and independent variables. From the Chi-square Test of association, the incidence of pregnancy was associated with WHO clinical stage, illness due to co-infection, Spouse's HIV status, marital status, educational level, place of residence, Contraception use, CD4 cell count, time of ART, body weight, occupation, age and child alive before ART follow-up, at 5 % level of significance (Table 1).

Table 1: Socio-demographic and clinical characteristics of HIV positive women on ART follow up in Finote Selam general hospital, Oct. 2016 to Sep. 2019 (n=429) and Chi-square Tests of association.

Variables

Categories

Pregnancy not occurred

Pregnancy occurred

Total

 

Pearson Chi-square

(Sig.)

Count (%)

Count (%)

n (%)

WHO clinical stage

Stage I

47 (13.9)

54 (59.3)

101 (23.5)

91.791 (0.000)

Stage II

127 (37.6)

29 (31.9)

156 (36.4)

Stage III

115 (34.0)

5 (5.5)

120 (28.0)

Stage IV

49 (14.5)

3 (3.3)

52 (12.1)

Illness due to co-infection

No

154 (45.6)

78 (85.7)

232 (54.1)

46.546 (0.000)

Yes

184 (54.4)

13 (14.3)

197 (45.9)

Spouse's HIV status

Negative

91 (26.9)

26 (28.6)

117 (27.3)

29.950 (0.000)

Positive

49 (14.5)

35 (38.5)

84 (19.6)

Unknown

198 (58.6)

30 (33.0)

228 (53.1)

Marital status

Married

144 (42.6)

81 (89.0)

225 (52.4)

62.014 (0.000)

Unmarried

43 (12.7)

3 (3.3)

46 (10.7)

Divorced

81 (24.0)

4 (4.4)

85 (19.8)

Windowed

70 (20.7)

3 (3.3)

73 (17.0)

Educational level

No education

84 (24.9)

10 (11.0)

94 (21.9)

27.392 (0.000)

Primary

134 (39.6)

26 (28.6)

160 (37.3)

Secondary

88 (26.0)

30 (33.0)

118 (27.5)

College and above

32 (9.5)

25 (27.5)

57 (13.3)

Residence

Rural

41 (12.1)

4 (4.4)

45 (10.5)

4.568 (0.033)

Urban

297 (87.9)

87 (95.6)

384 (89.5)

Contraceptive use

Never

206 (60.9)

67 (73.6)

273 (63.6)

18.352 (0.000)

Rarely

29 (8.6)

15 (16.5)

44 (10.3)

Mostly

38 (11.2)

5 (5.5)

43 (10.0)

Always

65 (19.2)

4 (4.4)

69 (16.1)

CD4 cell count

< 250

136 (40.2)

4 (4.4)

140 (32.6)

66.558 (0.000)

250-350

74 (21.9)

10 (11.0)

84 (19.6)

351-500

60 (17.8)

31 (34.1)

91 (21.2)

> 500

68 (20.1)

46 (50.5)

114 (26.6)

Time of ART follow-up

24 months

185 (54.7)

24 (26.4)

209 (48.7)

26.229 (0.000)

25-48 months

76 (22.5)

41 (45.1)

117 (27.3)

> 48 months

77 (22.8)

26 (28.6)

103 (24.0)

Occupation

Employed

68 (20.1)

49 (53.8)

117 (27.3)

46.716 (0.000)

Unemployed

147 (43.5)

13 (14.3)

160 (37.3)

Housewife

123 (36.4)

29 (31.9)

152 (35.4)

Body Weight

< 50 kg

113 (33.4)

8 (8.8)

121 (28.2)

36.462 (0.000)

50-60 kg

153 (45.3)

38 (41.8)

191(44.5)

> 60 kg

72 (21.3)

45 (49.5)

117 (27.3)

Age

15-24

45 (13.3)

24 (26.4)

69 (16.1)

22.942 (0.000)

25-29

102 (30.2)

39 (42.9)

141 (32.9)

30-35

92 (27.2)

19 (20.9)

111 (25.9)

> 35

99 (29.3)

9 (9.9)

108 (25.2)

Child of women

Have no child

104 (30.8)

54 (59.3)

158 (36.8)

25.157 (0.000)

Have a child

234 (69.2)

37 (40.7)

271 (63.2)

Incidence of pregnancy

 

338 (78.8)

91(21.2)

 

 

Result of Multiple Logistic Regression Analysis
Multiple binary logistic regression was used to identify the important predictors of incidence of pregnancy. The result of this analysis showed the estimated coefficients, odds ratio, p-value, Wald statistic, and 95 % confidence interval. The significance of the Wald statistic tells the importance of the predictor variable in the model. The result revealed that variables such as WHO clinical stage, spouse’s HIV status, marital status, contraception use, and time on ART follow-up, body weight, occupation, age, CD4 cell count, and child alive before ART follow-up were found the significant predictors of incidence of pregnancy at 5 % of the level of significance. Based on the result, the odds of incidence of pregnancy in women under WHO clinical stage II was 0.277 (95 % CI, 0.062-1.228) times less likely than in stage I. The odds ratio of unmarried, divorced, and widowed women were 0.013 (95 % CI, 0.002-0.101), 0.007 (95 % CI, 0.001-0.065), and 0.020 (95 % CI, 0.001-0.268) respectively, which indicates that unmarried, divorced and widowed women were 98.7 %, 99.3 % and 98 % less likely to be pregnant than married women respectively. Based on the result, CD4 count was a significant predictor of the incidence of pregnancy. HIV-positive women who had a CD4 count greater than 500 cells count were 9.522 (95 % CI, 1.265-71.674) times more likely to be pregnant compared to women who had a CD4 count of less than 250 cell/mm3. According to the time of ART follow-up, women who followed ART for 25-48 months were 21.363 (95 % CI, 3.750-121.681) times more likely to have pregnancy compared to the reference group. The body weight of women was positively and significantly related to the incidence of pregnancy. The odds ratio of women who had body weight between 50 and 60 kilograms was 55 % (95 % CI, 0.325-7.387) more likely to be pregnant than women who had body weight less than 50 kilograms. Moreover, occupation is also a significant predictor of the incidence of pregnancy; unemployed women were 0.097 (95 % CI, 0.019-0.490) times less likely to be pregnant than employed women. Finally, the odds of women having a child being pregnant were reduced by 84.9 % (95 % CI, 0.041-0.554) as compared to those women with no child before ART follow-up (Table 2).

Table 2: Result of Multiple Logistic Regression Analysis of incidence of pregnancy among HIV positive women on ART in Finote Selam general hospital, Oct. 2016 to Sep. 2019

Covariate

Category

B

S.E.

Wald

df

Sig.

Exp(B)

 

95.% CI EXP(B)

Lower

Upper

WHO clinical stage

Stage I (ref.)

 

 

16.320

3

.001*

 

 

 

 Stage II

-1.285

.760

2.857

1

.091

.277

.062

1.228

Stage III

-5.085

1.310

15.065

1

.000*

.006

.000

.081

Stage IV

-3.745

1.846

4.114

1

.043*

.024

.001

.882

Spouse's HIV status

Negative (ref.)

 

 

6.871

2

.032*

 

 

 

Positive

1.614

.742

4.725

1

.030*

5.023

1.172

21.526

Unknown

-.464

.761

.371

1

.542

.629

.141

2.797

Marital status

 

Married (ref.)

 

 

25.368

3

.000*

 

 

 

Unmarried

-4.326

1.040

17.315

1

.000*

.013

.002

.101

Divorced

-4.904

1.111

19.485

1

.000*

.007

.001

.065

Widowed

-3.920

1.328

8.715

1

.003*

.020

.001

.268

Contraception use

 

Never(ref.)

 

 

19.940

3

.000*

 

 

 

Rarely

-.1.026

.978

1.102

1

.294

.358

.053

2.435

Mostly

-4.100

1.105

13.774

1

.000*

.017

.002

.144

Always

-3.671

1.106

11.019

1

.001*

.025

.003

.222

CD4 cell count

< 250 (ref.)

 

 

22.550

3

.000*

 

 

 

250-350

-2.700

1.286

4.410

1

.036*

.067

.005

.835

351-500

1.594

1.060

2.263

1

.133

4.925

.617

39.322

> 500

2.254

1.030

4.789

1

.029*

9.522

1.265

71.674

Time on ART follow up

> =24 months

 

 

11.978

2

.003*

 

 

 

25-48 months

3.062

.888

11.897

1

.001*

21.363

3.750

121.681

> 48 months

2.135

.926

5.315

1

.021*

8.460

1.377

51.973

Body weight of women

< 50 kg (ref.)

 

 

6.284

2

.043*

 

 

 

50-60 kg

.438

.797

.303

1

.582

1.550

.325

7.387

> 60 kg

1.949

.907

4.616

1

.032*

7.018

1.186

41.515

Occupation

 

Employed(ref.)

 

 

10.108

2

.006*

 

 

 

Unemployed

-2.334

.827

7.976

1

.005*

.097

.019

.490

Housewife

-2.636

.904

8.499

1

.004*

.072

.012

.422

Age

 

15-24 (ref.)

 

 

16.401

3

.001*

 

 

 

25-29

.166

.761

.048

1

.827

1.181

.266

5.249

30-35

-2.423

1.030

5.538

1

.019*

.089

.012

.667

> 35

-5.035

1.333

14.255

1

.000*

.007

.000

.089

Child alive

Have a child

-1.892

.664

8.111

1

.004*

.151

.041

.554

Constant

 

1.569

2.442

.413

1

.520

4.804

 

 

ref.=Reference category which is the first category; *=significant at 5 % significance level

Discussions
The objective of this study was to assess the prevalence and to identify the important predictors of incidence of pregnancy of HIV positive women on ART follow up. As per the result of descriptive analysis, out of 429 samples about 91 (21.2 %) of women had pregnancy during the follow up. From multiple logistic regression analysis, WHO clinical stage, spouse’s HIV status, marital status, contraception use, body weight, child alive before ART, occupation, CD4 cell count, age and time of ART follow-up were significant predictors at 5 % level of significance.

The study has shown that WHO clinical stage was an important significant variable of incidence of pregnancy. According to the result of this study, women who are under advanced WHO clinical stage were less likely to become pregnant. That is, incidence of pregnancy was negatively related with WHO clinical stage, when the stages become increase, the incidence of pregnancy decrease. This implies that women who had WHO clinical stage I were more likely to be pregnant and this result is supported by the studies [7,9]. This difference might be due to those women in stage I at initiation of ART have a better health.

Marital status of women was also significant predictor for the incidence of pregnancy of HIV positive women. The result indicates that married women were more likely to be pregnant than other category. This finding is similar with the study in Ethiopia, Uganda and Brazil [7,8,11,13,14]. The possible reason for the explanation might be differences in the size of records reviewed, the study period, and marital status is the clear indicator of sexual activity of an individual.

From the result contraception use of women was a significant predictor of incidence of pregnancy. Women who ever-used contraception (mostly, always) were less likely to became pregnant than women who never use contraception and this is supported by the study of [8,11].

As shown from the result, CD4 cell count was strong significant predictors and positively related with incidence of pregnancy. The incidence of pregnancy during ART follow-up was highest among women with CD4 count greater than 500 cell/mm3. The incidence of pregnancy of women was increased with increasing of CD4 cell count. The result is consistent with the study of [10,13] and inconsistent with the study of [11]. The possible justification might be due to that fertility desire increases when CD4 cells count are higher, which subsequently increases the possibility of HIV infected women to become pregnant.

Time of ART follow-up was important predictor and positively related with incidence of pregnancy. Women on ART for 25-48 months were 21.363 times more likely to become pregnant than women on ART less than 25 months and women on ART for more than 48 months were 8.46 times more likely to become pregnant than women less than 25 months. This indicate that longer time on ART follow-up were associated with increasing probability of becoming pregnant. This finding was in line with the study in Malawi and Uganda [9,12].

Body weight of women was significant predictor for incidence of pregnancy. From the output, women who had body weight between 50and 60 kilogram were more likely to be pregnant than women who had body weight less than 50 kilogram. Additionally, women who had body weight greater than 60 kilogram were more likely to be pregnant compared with the reference group and this study was similar with the studies of [7, 11].

Based on the result, occupation of women was significant predictor of incidence of pregnancy. Both unemployed and housewife women were less likely to be pregnant compared to employed women. This implies that incidence of pregnancy was higher in employed patient women than other groups on ART follow-up. This result was consistent with the study in sub-Saharan Africa and Ethiopia [14] and inconsistent with the study by [9] in Malawi. The possible explanation of this finding might be due to the fact that in most circumstances in Ethiopia employed women are those with better educational status and they could be financially secured.

The study revealed that age of women was a significantly and negatively related with incidence of pregnancy on ART follow-up. The prevalence of pregnancy during the follow-up was higher among younger women aged 15-24 and 25-29, than older women. This indicate that there was decreasing the probability of incidence of pregnancy with increasing age of women. These results are expected because women are generally most fertile between the ages of 20 and 24 years and as they get older the likelihood of getting pregnant decreases. This finding was supported by similar findings in sub- Saharan Africa, Malawi, Uganda and Brazil [7,8,9,10,11,13]. The explanation is probably that it is more common for women in having children at a younger age in Ethiopia and the fact that younger women are generally more fertile.

The result of our study indicates that number of child alive before ART follow-up was another important significant variable for incidence of pregnancy. Women who have no child were more likely to become pregnant compared to women who had child. Likewise, women who had fewer children were more likely to become pregnant compared to women who had more. This result was consistent with the finding of [11,14] and inconsistent with the study of [13].

Conclusions
The aim of the study was to assess the prevalence and to identify the important predictors of incidence of pregnancy among HIV positive women under ART follow-up of reproductive ages in Finote Selam general Hospital. Both chi-square test and binary logistic regression analysis were employed. Out of total sample about 21.2 % of women had pregnancy during ART follow up. From logistic regression result, the significant predictors of incidence of pregnancy on HIV positive women under ART follow up were WHO clinical stage, spouse’s HIV status, marital status, use of contraception, CD4 count, time of ART follow-up, body weight, occupation, age and child alive. Women with advance WHO clinical stage were less likely to be pregnant. Women being married, being employed, never use contraceptive, had HIV positive spouse, had child were more likely to have pregnancy on the follow up. When CD4 cell count and body weight increase, incidence of pregnancy also increases and women who had longer time on ART follow up were more likely to be pregnant.

Based on the findings of this study, the following recommendations were made:

  1. Zonal Health Department and health institutions should be cautious when the patients have faced advanced WHO clinical stage and low CD4 count.
  2. Effective counseling strategies have to be designed focusing on unemployed, housewife mothers and mothers with no children at enrollment to encourage pregnancy.
  3. We would like to put remarks of increasing employment of HIV Positive women, providing effective services of ART health care, and studying further investigation for the general wellbeing of mothers and their respective potentially born children.

Abbreviations
AIDS: Acquired Immunodeficiency Syndrome ART: Antiretroviral Therapy
ARV: Antiretroviral Drugs
CD4: Cluster designation 4 positive lymphocytes HIV: Human Immunodeficiency Virus
MLE: Maximum Likelihood Estimation OR: Odds Ratio
UNAIDS: United Nations AIDS Programme
USAID: United State Agency for International Development
WHO: World Health Organization

Declarations
Availability of data and materials

The primary data set collected from households and analyzed during the current study is available from the corresponding author.

Funding: We declare that we did not receive any funding for this work.

Consent for publication: Not applicable.

Competing interests: The authors declare that they have no competing interests

Acknowledgments
I would like to acknowledge all the study participants and data collectors for their willingness to take in this study.
I would like to express our heartfelt gratitude to those who have helped us substantiate our research.

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