Since 1977 the International Centre for Diarrhoeal Disease Research, Bangladesh, has conducted a field experiment in family planning and MCH in its Matlab research station. The project began with an emphasis on family planning and MCH services were added in stages. This paper uses time series regression methods to address the question of whether the addition of health services contributed to family planning efficacy in Matlab in a program launched with minimal MCH services. The results show that some MCH interventions increased contraceptive prevalence, some decreased it, and others had no effect. The broader significance of these findings for implementing integrated programs is discussed.