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Assistant Scientist

Contact Info

Research Interests

Fertility; Contraception; Family planning; Couples; Fertility preferences; Survey research; Sexual and reproductive health; Women’s health
Experiences & Accomplishments
I have a PhD from the Johns Hopkins Bloomberg School of Public Health in the Department of Population, Family and Reproductive Health. My education and experience reflect my commitment and passion to sexual and reproductive health and demography, particularly their intersection around fertility. Broadly, I’m interested in what conditions and policies support women achieving their child- bearing and spacing goals. Specifically, I have been studying how fertility preferences and contraception intentions influence contraceptive use dynamics in countries experiencing fertility transitions. My research portfolio includes work on: fertility preferences and contraceptive use dynamics in sub-Saharan Africa, covert use of contraception in sub-Saharan Africa, and couples and reproductive health. In addition, I have experience in survey research design and implementation, both in my work with PMA and The Commonwealth Fund. I have participated in all stages of survey work, including survey design, survey implementation (in-country trainings for interviewers, creating training videos for local teams), data quality and monitoring in the field, analysis of data to produce manuscripts, and leading seminars for researchers on how to analyze data.
Honors & Awards
2021 Provost’s Office Covid Relief Dissertation Completion Fellowship Grant, Johns Hopkins Bloomberg School of Public Health
2021 Dean’s PhD Tuition Scholarship, Johns Hopkins Bloomberg School of Public Health
2020 Fund in Recognition of Laurie Schwab Zabin for Population and Family Planning Students, Johns Hopkins Bloomberg School of Public Health
2019 Carl Swan Shultz Endowment Fund Award, Johns Hopkins Bloomberg School of Public Health
2018 Caroline Cochran Scholarship Fund Award, Johns Hopkins Bloomberg School of Public Health
2006 Graduated cum laude, Princeton University
Select Publications
Peer Reviewed Publications
  • Sarnak DO, Gemmill A. Perceptions of Partners' Fertility Preferences and Women's Covert Contraceptive Use in Eight Sub-Saharan African Countries. Stud Fam Plann. 2022 Sep;53(3):527-548. doi: 10.1111/sifp.12206. Epub 2022 Jun 29. PMID: 35767464
  • Sarnak DO, Gummerson E, Wood SN, OlaOlorun FM, Kibira SPS, Zimmerman LA, Anglewicz P. Prevalence and characteristics of covert contraceptive use in the Performance Monitoring for Action multi-country study. Contracept X. 2022 May 6;4:100077. doi: 10.1016/j.conx.2022.100077. eCollection 2022. PMID: 35620730
  • Zimmerman LA, Sarnak DO, Karp C, Wood SN, Yihdego M, Shiferaw S, Seme A. Measuring experiences and concerns surrounding contraceptive induced side-effects in a nationally representative sample of contraceptive users: Evidence from PMA Ethiopia. Contracept X. 2022 Mar 19;4:100074. doi: 10.1016/j.conx.2022.100074. eCollection 2022. PMID: 35368853
  • Sarnak DO, Squires D, Kuzmak G, Bishop S. Paying for Prescription Drugs Around the World: Why Is the U.S. an Outlier? Issue Brief (Commonw Fund). 2017 Oct 1;2017:1-14. PMID: 28990747
  • Zimmerman LA, Sarnak DO, Karp C, Wood SN, Moreau C, Kibira SPS, Makumbi F. Family Planning Beliefs and Their Association with Contraceptive Use Dynamics: Results from a Longitudinal Study in Uganda. Stud Fam Plann. 2021 Sep;52(3):241-258. doi: 10.1111/sifp.12153. Epub 2021 May 20. PMID: 34015142