Low-birth-weight (LBW) is a major adverse pregnancy outcome in resource-poor countries. About 28% of all neonatal deaths worldwide are directly attributed to LBW. Exposure to biomass fuel during cooking is associated with LBW. There is unlikely to be any significant change in the use of biomass fuels in the near future, therefore, interventions targeted to reduce the harmful effects on poor pregnancy outcomes is warranted. To address this need, the investigators proposed a locally-made inexpensive prefabricated model of the "100-dollar-kitchen"($100Kitchen) with an improved cookstove for resource-poor settings. The improved cookstove of the $100Kitchen ensure complete incineration of the biomass fuels and thus, provided safeguard to the pregnant women using these fuels. This study has been measured the impact of our '$100Kitchen and improved cookstove' intervention as to whether a pregnant woman residing in a household with a '$100Kitchen and improved cookstove' is less likely to give birth to a LBW newborn. A cluster-randomized controlled trial has been adopted in Shahjadpur sub-district in Bangladesh and 628 and 639 pregnant women at 8-12 weeks gestational age enrolled for each intervention and control area respectively and followed-up through 42-days post-delivery. Birth outcomes have been noted and the newborns have been weighted within 72-hrs of the delivery. Non-invasive maternal blood Carbon Monoxide Hemoglobin saturation (SpCO) level between the intervention and control groups have also been measured.

A single-stage cluster sampling was followed. All the 'mouzas' (revenue villages) in Shahjadpur sub-district were divided into clusters so that each cluster contained a population of about 3,000. This generated 188 clusters. 104 out of 188 clusters-52 clusters for the intervention and 52 clusters for the control group - were randomly selected for the study to enroll the required 1300 pregnant women. Each cluster was then randomly allocated to either the intervention or control group using a computer generated random sequence. The random allocation sequence was generated independently by a statistician, who had no further involvement with the study. Once allocated, in each cluster all the eligible pregnant women were identified, invited, and enrolled during door-to-door visits by the project field staff. The field staff included female health workers, with the help of existing government community health workers such as family welfare assistants. A total of 628 eligible pregnant women were enrolled in the intervention clusters and a total of 639 eligible pregnant women in the control clusters. During the enrolment in the intervention clusters, a $100Kitchen with the improved cookstoves was installed at each of the 628 pregnant women's households following the verbal and written consent of the women and the household head.

Inclusion Criteria:

• Pregnant women at 8 to 12 weeks gestational age

Exclusion Criteria:

• Pregnant women more than 12 weeks gestational age