Effects of Birth Spacing on Maternal, Perinatal, Infant, and Child Health: A Systematic Review of Causal Mechanisms
Agustín Conde-Agudelo,
Anyeli Rosas-Bermudez,
Fabio Castaño,
Maureen H. Norton,
Agustín Conde-Agudelo
World Health Organization Collaborating Centre in Human Reproduction, Universidad del Valle, Cali, Colombia.
Search for more papers by this authorAnyeli Rosas-Bermudez
Perinatal Researchers, World Health Organization Collaborating Centre in Human Reproduction, Universidad del Valle, Cali, Colombia.
Search for more papers by this authorFabio Castaño
Principal Technical Advisor for Family Planning, Reproductive Health, and Quality Improvement Management Sciences for Health, Arlington, VA. At the time of the study, he was Technical Director, Extending Service Delivery Project, Management Sciences for Health, Washington, DC.
Search for more papers by this authorMaureen H. Norton
Senior Technical Advisor, Office of Population and Reproductive Health, Bureau for Global Health, United States Agency for International Development, Washington, DC. E-mail: [email protected] .
Search for more papers by this authorAgustín Conde-Agudelo,
Anyeli Rosas-Bermudez,
Fabio Castaño,
Maureen H. Norton,
Agustín Conde-Agudelo
World Health Organization Collaborating Centre in Human Reproduction, Universidad del Valle, Cali, Colombia.
Search for more papers by this authorAnyeli Rosas-Bermudez
Perinatal Researchers, World Health Organization Collaborating Centre in Human Reproduction, Universidad del Valle, Cali, Colombia.
Search for more papers by this authorFabio Castaño
Principal Technical Advisor for Family Planning, Reproductive Health, and Quality Improvement Management Sciences for Health, Arlington, VA. At the time of the study, he was Technical Director, Extending Service Delivery Project, Management Sciences for Health, Washington, DC.
Search for more papers by this authorMaureen H. Norton
Senior Technical Advisor, Office of Population and Reproductive Health, Bureau for Global Health, United States Agency for International Development, Washington, DC. E-mail: [email protected] .
Search for more papers by this authorAbstract
This systematic review of 58 observational studies identified hypothetical causal mechanisms explaining the effects of short and long intervals between pregnancies on maternal, perinatal, infant, and child health, and critically examined the scientific evidence for each causal mechanism hypothesized. The following hypothetical causal mechanisms for explaining the association between short intervals and adverse outcomes were identified: maternal nutritional depletion, folate depletion, cervical insufficiency, vertical transmission of infections, suboptimal lactation related to breastfeeding–pregnancy overlap, sibling competition, transmission of infectious diseases among siblings, incomplete healing of uterine scar from previous cesarean delivery, and abnormal remodeling of endometrial blood vessels. Women's physiological regression is the only hypothetical causal mechanism that has been proposed to explain the association between long intervals and adverse outcomes. We found growing evidence supporting most of these hypotheses.
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