In February 2004, in an attempt to improve Kenya's record, the government obliged the owners of the country's 25,000 matatus (minibuses), the backbone of public transportation, to install new safety equipment on their vehicles. Government spending on road projects is also planned. Barack Obama Sr., the father of the former U.S. president, was in several serious drunk driving accidents which paralysed him. He was later killed in a drink driving accident . The child mortality per 1000 live birth has reduced form 98.1 in 1990 to 51 in 2015, this compares to the global statistics of child mortality which has dropped from 93 in 1990 to 41 in 2016. . The infant mortality rate has also reduced form 65.8 in 1990 to 35.5 in 2015 while the neonatal mortality rate per 1000 live births is 22.2 in 2015. Maternal mortality is defined as "the death of a woman while pregnant or within 42 days of termination of pregnancy, irrespective of the duration and site of the pregnancy, from any cause related to or aggravated by the pregnancy or its management but not from accidental or incidental causes". Over 500,000 women globally die every year due to maternal causes, and half of all global maternal deaths occur in sub-Saharan Africa. The 2010 maternal mortality rate per 100,000 births for Kenya is 530, yet has been shown to be as high as 1000 in the North Eastern Province, for example. This is compared with 413.4 in 2008 and 452.3 in 1990. In Kenya the number of midwives per 1,000 live births is unavailable and the lifetime risk of death for pregnant women 1 in 38. Women under 24 years of age are especially vulnerable because the risk of developing complications during pregnancy and childbirth. The burden of maternal mortality extends far beyond the physical and mental health implications. In 1997, the Gross Domestic Product (GDP) loss attributable to MMR per 100,000 live births was $234 US, one of the highest losses compared to other African regions. Additionally, with the annual number of maternal deaths being 6222, the total annual economic loss due to maternal mortality in Kenya was $2240 US, again one of the highest losses compared to other African regions. Kenya's health infrastructure suffers from urban-rural and regional imbalances, lack of investment, and a personnel shortage, with, for example, one doctor for 10,150 people (as of 2000). The determinants influencing maternal mortality and morbidity can be categorised under three domains: proximate, intermediate, and contextual.