Abstract: Background and Rationale: Obstetric ultrasounds have become a routine practice in pregnancy management globally. Evidence, however, suggests that while obstetric scans in high-income countries are associated with positive experiences to mothers, the technology may not be having similar positive impact in low-and middle- income countries. Available evidence shows the detrimental impact of obstetric ultrasounds on fetal sex identification and consequent abortions of female fetuses in India. Studies from Vietnam, Tanzania and Uganda suggest some women have started perceiving ultrasound scans as the entirety of antenatal care. Other studies suggest mothers are overestimating the diagnostic abilities of ultrasound technology to the point where they are not receiving the appropriate care. The concerning nature of the current evidence available in the literature indicates the need for a detailed, qualitative investigation that examines both women and providers’ understandings and practices of obstetric ultrasound use. Objective: To explore the impact of ultrasound technology on both the biomedical, and lay, cultural management of pregnancy in Rural Pakistan. Method: Data were drawn from two qualitative research projects conducted in Pakistan between 2009 and 2015. The first study, entitled “Are community midwives addressing the inequities in access to skilled birth attendance in Pakistan? Gender, class, and social exclusion”, used a mixed methods approach - an institutional ethnography and a cross-sectional survey to explore whether a new cadre of midwives were improving access to skilled maternity care for poor and socially excluded women in two districts – Layyah and Jhelum in Punjab. Qualitative data were collected using in-depth interviews with 83 health care providers and 139 community members, and 180 formal and informal observations of patient-provider interactions in health facilities. The survey interviewed 1457 women who had given birth in the two years prior. The second project, “Addressing disparities in maternal health care in Pakistan: gender, class and exclusion” is a critical ethnography of maternal health services in a village in Chakwal, Punjab. Data were generated over the course of 10-months using 134 observations, 94 in-depth interviews, and 11 focus group discussions. Transcripts were selected if they contained the term “ultrasound” and related terms, e.g., “scan”. Qualitative data were organized using Quirkos software and analyzed through thematic analysis. The survey data were analysed using STATA 14. Results: Our findings revealed that an obstetric ultrasound was a common procedure for pregnant women in rural Pakistan as part of their pregnancy management. In fact, the data suggests women perceived the scan as synonymous with antenatal care and assumed it was an integral part of their antenatal visit, irrespective of any stated medical indication. It was sometimes the only care they sought during pregnancy, with 80% reporting a scan while only 49% reported receiving a blood test, blood pressure measurement or a urinalysis. A common reason underlying these patterns of use was the mothers’ strong trust in ultrasound technology’s abilities to diagnose ill-health broadly and believing it alone would ensure a healthy pregnancy and healthy baby. So strong was this trust in the powers of ultrasound technology, that mothers expected delivery dates and fetal sex reports to be precise. Any deviations were unacceptable. Wider societal level forces – a highly privatized health care sector and strong son-preference - are driving a mutually reinforcing supplydemand cycle of potentially unnecessary scans during a healthy pregnancy. Researchers observed the providers, mostly in the private sector implementing different strategies to market their ultrasound services including prioritizing ultrasound scans during appointments over other elements of antenatal care, encouraging monthly scans, and offering special discounts. A desire to ensure birth of a son is driving pregnant women’s demand for repeat scans in the hope of either expecting a different ‘diagnosis’ if a female fetus is suspected or repeatedly confirming a male fetus. Conclusions: Obstetric ultrasound has become the preferred method of surveillance to women during healthy pregnancies to the extent that its use is understood as synonymous and equivalent to antenatal care. It appears that both providers, particularly those in the profit-driven private sector, and patients have mutually reinforced the demand for un-necessary ultrasound scans during pregnancy. Given the limited role of obstetric ultrasound in pregnancy surveillance, it is important to ensure that the technology does not replace routine elements of antenatal care. While a culture that prizes sons is not going to be easily amenable to change, health policy makers can address the market forces underlying the for-profit private health care sector to the limit unscrupulous use of ultrasound technology. Measures must be taken to ensure that health care provision for women during pregnancy is driven not by profit, but by medical recommendation.