Study design and participants
Institution based cross sectional study was conducted among HIV-positive women in Afar region, Ethiopia in May 2018. Afar region is one of nine region in Ethiopia and it has population projection of 1.8 million [22]. The region has five hospital: Dubti General Hospital, Aysaita primary hospiatal, Yalo primary hospital and Mohammed Akle general Hospita. The study was conducted in Dubti and Mohammed Akle General Hospital after simple random selection method. The hospitals provide Adult and Pediatric ART clinic, and Voluntary Counseling and Testing services.
Debuti general hospital is located in zone one of Afar region and 605 km Northeast of Addis Ababa (the capital city of Ethiopia). According to the hospital administration report, Dubti general hospital has a total of 2329 people living with HIV (PLHIV) were ever enrolled in the ART clinic, and a total of 785 women were on ART during the data collection period. It provides health care services for a catchment population of approximately 500,000 people in semera city administration and adjacent districts
Mohammed Akle general hospital is located in zone three of Afar region and 350 km Northeast of Addis Ababa. It has a total of 1824 populations living with HIV (PLHIV) ever enrolled in the ART clinic, and a total of 527 women were on ART during the data collection period. It provides health care services for a catchment population of approximately 250,000 people in zone three and adjacent districts.
Sample Size Determination and Sampling Techniques
The sample size was determined using single population proportion formula with assumption: 5% type one error, 95% confidence interval (CI), 52.9% proportion of fertility desire among reproductive age women in Harare Hospital [20]. Then, we added 5% to compensate for the nonresponse of participants and the final sample size was 402.

Where: n= required sample size, Zα/2= critical value for normal distribution at 95% confidence level (1.96), p=proportion of fertility desire among reproductive age women, d= 0.05 (5% margin of error)
Out of the five hospitals in Afar region, Dubti and Mohammed Akle General Hospital were selected by simple lottery method. The samples were proportionally allocated to each hospital. A systematic random sampling technique was employed to enroll the study participants. Accordingly, every three participant was selected using a systematic random sampling technique till the required sample size reached.
Study variables
Dependent variable: In this study the dependent variable was ‘fertility desire’ among reproductive age women enrolled in ART clinic. Fertility desire is the intention to have children between fertile ages from 15-49 years (1). Women who were desire to have children was coded as ‘1’, while those who didn’t have desire was coded as ‘0’ for logistic regression analysis.
Independent variables: The independent variables were socio-demographic characteristics (residence, age, religion, marital status, educational status, and community influence), and clinical and reproductive characteristics (previous life birth, , number of children, time since HIV diagnosed, current CD4 count, partner HIV status, and disclosure status to partner)
Data collection tools and techniques
Data were collected using a pre-tested, structured and interviewer administered questionnaire adapted from literature reviews and the Ethiopian Demographic and Health Survey [EDHS]. Women were interviewed, at the hospitals during their follow up visit. The questionnaire was prepared first in English and translated in to Amharic then back to English to check for consistency. The Amharic version of the questionnaire was used to collect the data. The tool was pretested on 5% of women on ART clinic other than selected hospital in Aysaita primary hospital. The data was collected by four diploma Nurses. The data collectors and the supervisors (two BSc nurses) were trained for 2 days by the principal investigator on the study instrument, objective, consent form, how to approach study participants, and confidentiality.
Data quality control
Diploma Nurses who can speak the local language were recruited as data collectors. The questionnaire was pretested on 5 % of the participants before the initiation of the study. The pretest was done to ensure wordings, logical sequence, clarity, and skip patterns of the questions. Then the pretest amendments on the questionnaire were made accordingly. The supervisors checked the day to day activities of data collectors regarding the completion of questionnaires, clarity of responses and proper coding of the responses.
Data management and Analysis
The data was checked for completeness, coded, recoded, and entered into Epi data version 3.1 software and exported to SPSS version 20 for analysis. The descriptive analysis was done and the results were presented using texts, frequency tables, and mean with standard deviation.
A binary logistic regression analysis was done to assess the association between the outcome variable with each explanatory variable. socio-demographic characteristics (residence, age, religion, marital status, educational status, community pressure), and reproductive and health services characteristics (previous life birth, , number of children, time since HIV diagnosed, Current CD4 count, partner HIV status, and Disclosure status to partner) were the explanatory variables included in the binary analysis. Thus, independent variables with p-value less than 0.25 were considered in the final model. Correlation between independent variables was assessed but we did not find any correlation between independent variables. The model fitness was also checked using Hosmer-Lemeshow model fit-ness test. Finally, multivariable logistic regression analysis was done to control potential confounders and to identify the factors associated with fertility desire among reproductive age women on ART. A statistical significance level was declared at a p-value of less than 0.05.
Ethical consideration
The study was approved by the Ethical Review Committee (ERC) of Samara University. An official letter was written from Samara University to Afar regional Health bureau. Then permission and support letter was written to Dubti and Mohammed Akle general hospitals. The participants enrolled in the study were informed about the study objectives, expected outcomes, benefits and the risks associated with it. A signed written consent was taken from the participants before the interview. Illiterate women were consented with their thumb print. Confidentiality of responses was maintained throughout the study.