Population under surveillance

To date more than 165,000 women have been enrolled in the study of whom 104,797 are currently being followed up (data from the end of February 2005, please see Table 1). The population is relatively mobile and 59,000 women have moved out of the study area to date. Only around 1000 women have withdrawn from the trial, a testimony to the effectiveness of our education campaign. There have been over 42,800 births and almost 45,000 completed pregnancies. In total 1428 deaths have been recorded among study women and of these 169 have occurred during pregnancy or during the 6-week postpartum period.

The current obstetric risk observed within the study population is 377 deaths per 100,000 completed pregnancies (please see Table 2 for definitions of measures of maternal health). This is lower than we had initially expected. This may be due to a reduction in deaths among those receiving vitamin A, but may also reflect a national trend of a reduction in maternal mortality. We will have to be patient and wait until 2009 to know which explanation is most likely!

During 2004, there was consolidation of all field and data management activities, continuing major inputs from London based staff (particularly in terms of statistical support, IEC strategy and assistance with Visual FoxPro) and an emphasis on capacity development training of key Ghanaian KHRC staff. The Trial Steering Committee and Data Monitoring and Ethics Committee both met during the year, and gave their approval for the work conducted to date. Members of the trial management team also attended the meeting of the International Vitamin A Consultative Group in Lima, Peru in November 2004 and held meetings with the team involved with the JIVITA study of vitamin A supplementation and maternal mortality being conducted in Bangladesh.

Plans for 2005 include the collection of socio-economic status data on all pregnant women, an expansion of the hospital data capture project and additional in-house training for all staff. Preliminary data is also being analysed and prepared for publication. In particular, Karen Edmond is coordinating a programme of work on the levels and determinants of neonatal mortality in the study area.

Table 1: Current status of women in the ObaapaVitA trial
Number of women	Kintampo	Wenchi	Techiman	Nkoranza	Total
Enrolled	41780	41398	55970	26649	165797
Active follow-up	24256	26651	34959	18857	104723
Ineligible	2	29	2	53	86
Moved between clusters	9263	9703	8494	3837	31297
Withdrawn	360	308	267	144	1079
Moved out of study area	17110	14044	20543	7500	59197
Died	456	418	373	181	1428
Died in pregnancy or six weeks post-partum	57	51	36	25	169
Completed pregnancies	14792	12855	11383	5788	44818
Births	14270	12227	10853	5470	42820

Table 2: Key Definitions for Maternal Health
Maternal deaths/ mortality	Deaths occurring during pregnancy or during the first 6 weeks after delivery. Deaths due to accidents and injuries are excluded.
Pregnancy-related deaths/ mortality	Deaths occurring during pregnancy or during the first 6 weeks after delivery. Deaths due to accidents and injuries are not excluded.
Maternal mortality ratio	The number of maternal deaths divided by the total number of live births. This ratio can be calculated from routine surveillance data and it is used as an approximate estimate of the true obstetric risk.
Obstetric risk	The number of pregnancy-related deaths divided by the number of completed pregnancies. The obstetric risk is the “gold standard” for studying deaths associated with pregnancy.

Key project staff at KHRC:

Principal non-KHRC project staff: